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Le Doare K, Gaylord MA, Anderson AS, Andrews N, Baker CJ, Bolcen S, Felek A, Giardina PC, Grube CD, Hall T, Hallis B, Izu A, Madhi SA, Maniatis P, Matheson M, Mawas F, McKeen A, Rhodes J, Alston B, Patel P, Schrag S, Simon R, Tan CY, Taylor S, Kwatra G, Gorringe A. Interlaboratory comparison of a multiplex immunoassay that measures human serum IgG antibodies against six-group B streptococcus polysaccharides. Hum Vaccin Immunother 2024; 20:2330138. [PMID: 38608170 PMCID: PMC11018077 DOI: 10.1080/21645515.2024.2330138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/09/2024] [Indexed: 04/14/2024] Open
Abstract
Measurement of IgG antibodies against group B streptococcus (GBS) capsular polysaccharide (CPS) by use of a standardized and internationally accepted multiplex immunoassay is important for the evaluation of candidate maternal GBS vaccines in order to compare results across studies. A standardized assay is also required if serocorrelates of protection against invasive GBS disease are to be established in infant sera for the six predominant GBS serotypes since it would permit the comparison of results across the six serotypes. We undertook an interlaboratory study across five laboratories that used standardized assay reagents and protocols with a panel of 44 human sera to measure IgG antibodies against GBS CPS serotypes Ia, Ib, II, III, IV, and V. The within-laboratory intermediate precision, which included factors like the lot of coated beads, laboratory analyst, and day, was generally below 20% relative standard deviation (RSD) for all six serotypes, across all five laboratories. The cross-laboratory reproducibility was < 25% RSD for all six serotypes, which demonstrated the consistency of results across the different laboratories. Additionally, anti-CPS IgG concentrations for the 44-member human serum panel were established. The results of this study showed assay robustness and that the resultant anti-CPS IgG concentrations were reproducible across laboratories for the six GBS CPS serotypes when the standardized assay was used.
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Affiliation(s)
- Kirsty Le Doare
- Centre for Neonatal and Paediatric Infection, Institute for Infection and Immunity, St George’s, University of London, London, UK
- Makerere University Johns Hopkins University, Kampala, Uganda
- UK Health Security Agency, Porton Down, UK
| | | | | | - Nick Andrews
- Immunisation and Vaccine Preventable Diseases Division, United Kingdom Health Security Agency (UKHSA), London, UK
| | - Carol J. Baker
- Department of Pediatrics, Division of Infectious Disease, McGovern Medical School and UT Health, Houston, TX, USA
| | - Shanna Bolcen
- The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Arif Felek
- Vaccine Division, Scientific Research & Innovation Group, MHRA, Potters Bar, UK
| | | | | | - Tom Hall
- Centre for Neonatal and Paediatric Infection, Institute for Infection and Immunity, St George’s, University of London, London, UK
| | | | - Alane Izu
- South African Medical Research Council: Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa
| | - Shabir A. Madhi
- South African Medical Research Council: Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa
| | - Pete Maniatis
- The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | | | - Fatme Mawas
- Vaccine Division, Scientific Research & Innovation Group, MHRA, Potters Bar, UK
| | - Andrew McKeen
- Pfizer Global Biometrics & Data Management, Pearl River, NY, USA
| | - Julia Rhodes
- The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | | | - Palak Patel
- The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Stephanie Schrag
- The Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Raphael Simon
- Pfizer Vaccine Research & Development, Pearl River, NY, USA
| | - Charles Y. Tan
- Pfizer Global Biometrics & Data Management, Pearl River, NY, USA
| | | | - Gaurav Kwatra
- South African Medical Research Council: Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
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Gaylord MA, Larrier M, Giordano-Schmidt D, Grube CD, Singh S, Nguyen HH, McKeen A, Tan CY, Anderson AS, Kalina WV, Pavliakova D, Giardina PC. Development and validation of a 6-plex Luminex-based assay for measuring human serum antibodies to group B streptococcus capsular polysaccharides. Hum Vaccin Immunother 2024; 20:2311480. [PMID: 38608171 PMCID: PMC11018021 DOI: 10.1080/21645515.2024.2311480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/25/2024] [Indexed: 04/14/2024] Open
Abstract
Six serotypes (Ia, Ib, II, III, IV, and V) cause nearly all group B streptococcal (GBS) disease globally. Capsular polysaccharide (CPS) conjugate vaccines aim to prevent GBS disease, however, licensure of a vaccine would depend on a standardized serological assay for measuring anti-CPS IgG responses. A multiplex direct Luminex-based immunoassay (dLIA) has been developed to simultaneously measure the concentration of serum IgG specific for the six prevalent GBS CPS serotypes. Assay validation was performed using serum samples obtained from human subjects vaccinated with an investigational 6-valent GBS CPS conjugate vaccine. Results for the assay are expressed as IgG concentrations (µg/mL) using a human serum reference standard composed of pooled sera from vaccinated subjects. The lower limits of quantitation (LLOQ) for all serotypes covered in the 6-plex GBS IgG dLIA fell within the range of 0.002-0.022 µg/mL IgG. Taken together, the 6-plex GBS IgG dLIA platform is specific for the six GBS serotypes included in Pfizer's investigational vaccine, has a wide dilution adjusted assay range, and is precise (<18.5% relative standard deviation) for all serotypes, and, therefore, is suitable for quantitatively measuring vaccine-induced or naturally acquired serotype-specific anti-CPS IgG responses against GBS.
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Affiliation(s)
| | - Melissa Larrier
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, USA
| | | | | | - Suddham Singh
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, USA
| | - Ha H. Nguyen
- Global Biometrics & Data Management, Pfizer Inc, Pearl River, New York, USA
| | - Andrew McKeen
- Global Biometrics & Data Management, Pfizer Inc, Pearl River, New York, USA
| | - Charles Y. Tan
- Global Biometrics & Data Management, Pfizer Inc, Collegeville, PA, USA
| | | | - Warren V. Kalina
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, USA
| | - Danka Pavliakova
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, USA
| | - Peter C. Giardina
- Vaccine Research and Development, Pfizer Inc, Pearl River, New York, USA
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Saukkoriipi A, Silmon de Monerri NC, Toropainen M, Lindholm L, Veijola R, Toppari J, Knip M, Radley D, Gomme E, Jongihlati B, Anderson AS, Palmu AA, Simon R. Association between anti-capsular IgG levels at birth and risk of invasive group B streptococcus disease in Finnish newborns: a retrospective case-control study. THE LANCET. MICROBE 2024; 5:689-696. [PMID: 38679040 DOI: 10.1016/s2666-5247(24)00038-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 05/01/2024]
Abstract
BACKGROUND Group B streptococcus is a major cause of neonatal disease. Natural history studies have linked maternally transferred anti-group B streptococcus capsular polysaccharide antibodies with protection against infant group B streptococcus disease. Previous studies of capsular polysaccharide antibody concentration in European populations have used maternal (not infant) sera and a non-standardised assay. This study aimed to evaluate anti-capsular polysaccharide IgG concentrations associated with protection against invasive group B streptococcus disease in Finnish infants. METHODS In this retrospective case-control study, we used cord sera from the Finnish DIPP study repository, which was obtained between Jan 1, 1995, and Dec 31, 2017. We included infants aged 6 months or younger with group B streptococcus infection (cases) and healthy infants (controls). We enrolled infants with invasive neonatal group B streptococcus (55 cases) and matched controls (229 controls) aged 6 months or younger after identification from Finnish health registers. We measured anti-capsular polysaccharide IgG (serotypes Ia-V) concentration using a standardised immunoassay and we estimated its relationship to disease risk using a Bayesian model. We used the derived risk-concentration curve to predict potential efficacy of six-valent group B streptococcus capsular polysaccharide vaccine (GBS6) based on previously reported immunogenicity data. FINDINGS Most (32 [58%] of 55 cases) group B streptococcus cases were due to serotype III and anti-serotype III streptococcus capsular IgG concentrations were higher in serotype III-matched controls than in cases (p<0·001). 0·120-0·266 μg/mL serotype III-specific IgG was estimated to confer 75-90% risk reduction against serotype III disease. A universal risk-concentration curve, aggregating results across all six serotypes, yielded similar results. Application of this curve to GBS6 immunogenicity data predicted maternal immunisation to be more than 80% efficacious for prevention of infant group B streptococcus disease. INTERPRETATION Higher neonatal anti-capsular polysaccharide serum IgG concentration at birth correlated with reduced risk of infant group B streptococcus disease in Finland. Based on these results, a maternal group B streptococcus capsular conjugate vaccine currently in development is predicted to be efficacious. FUNDING Pfizer.
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Affiliation(s)
| | | | | | - Laura Lindholm
- Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Riitta Veijola
- Department of Pediatrics, Research Unit of Clinical Medicine, Medical Research Center, University of Oulu, Oulu, Finland; Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
| | - Jorma Toppari
- Institute of Biomedicine, Research Centre for Integrated Physiology and Pharmacology, Centre for Population Health Research, University of Turku, Turku, Finland; Department of Pediatrics, Turku University Hospital, Turku, Finland
| | - Mikael Knip
- Department of Pediatrics, Tampere University Hospital, Tampere, Finland; Pediatric Research Center, Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - David Radley
- Vaccine Research and Development, Pfizer, Pearl River, NY, USA
| | - Emily Gomme
- Vaccine Research and Development, Pfizer, Pearl River, NY, USA
| | | | | | - Arto A Palmu
- Finnish Institute for Health and Welfare, Tampere, Finland
| | - Raphael Simon
- Vaccine Research and Development, Pfizer, Pearl River, NY, USA.
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Pena JMS, Lannes-Costa PS, Nagao PE. Vaccines for Streptococcus agalactiae: current status and future perspectives. Front Immunol 2024; 15:1430901. [PMID: 38947337 PMCID: PMC11211565 DOI: 10.3389/fimmu.2024.1430901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/06/2024] [Indexed: 07/02/2024] Open
Abstract
A maternal vaccine to protect newborns against invasive Streptococcus agalactiae infection is a developing medical need. The vaccine should be offered during the third trimester of pregnancy and induce strong immune responses and placental transfer of protective antibodies. Polysaccharide vaccines against S. agalactiae conjugated to protein carriers are in advanced stages of development. Additionally, protein-based vaccines are also in development, showing great promise as they can provide protection regardless of serotype. Furthermore, safety concerns regarding a new vaccine are the main barriers identified. Here, we present vaccines in development and identified safety, cost, and efficacy concerns, especially in high-need, low-income countries.
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Affiliation(s)
- João Matheus Sobral Pena
- Laboratory of Molecular Biology and Physiology of Streptococci, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University - UERJ, Rio de Janeiro, Brazil
| | - Pamella Silva Lannes-Costa
- Laboratory of Molecular Biology and Physiology of Streptococci, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University - UERJ, Rio de Janeiro, Brazil
| | - Prescilla Emy Nagao
- Laboratory of Molecular Biology and Physiology of Streptococci, Institute of Biology Roberto Alcantara Gomes, Rio de Janeiro State University - UERJ, Rio de Janeiro, Brazil
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Karampatsas K, Hall T, Voysey M, Carreras-Abad C, Cochet M, Ramkhelawon L, Peregrine E, Andrews N, Heath PT, Le Doare K. Antibody kinetics between birth and three months of life in healthy infants with natural exposure to Group B streptococcus: A UK cohort study. Vaccine 2024; 42:3230-3238. [PMID: 38627147 DOI: 10.1016/j.vaccine.2024.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 03/11/2024] [Accepted: 04/04/2024] [Indexed: 04/29/2024]
Abstract
INTRODUCTION Capsular polysaccharide (CPS) serotype-specific Immunoglobulin G (IgG) in cord blood has been proposed as a correlate of protection against invasive Group B Streptococcus (iGBS) disease. Although protective levels are required in infants throughout the window of vulnerability up to 3 months of age, little is known regarding the kinetics of GBS-specific IgG over this period. METHODS We enrolled 33 healthy infants born to mothers colonized with GBS. We collected cord blood and infant blood samples either at one (21-35 days), two (49-63 days), or three months of age (77-91 days). We measured GBS serotype-specific CPS IgG concentrations and calculated the decay rate using a mixed-effects model. We further explored whether the antibody kinetics were affected by common maternal and infant factors and estimated the correlation between IgG concentration at birth and one, two, and three months of age. RESULTS The half-life estimate of IgG concentration for homologous and non-homologous GBS serotypes in paired samples with detectable IgG levels at both time points was 27.4 (95 % CI: 23.5-32.9) days. The decay rate did not vary by maternal age (p = 0.7), ethnicity (p = 0.1), gravida (p = 0.1), gestation (p = 0.7), and infant sex (p = 0.1). Predicted IgG titres above the assay lower limit of quantification on day 30 strongly correlated with titres at birth (Spearman correlation coefficient 0.71 [95 % CI: 0.60-0.80]). CONCLUSION Our results provide a basis for future investigations into the use of antibody kinetics in defining a serocorrelate of protection against late-onset iGBS disease.
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Affiliation(s)
- Konstantinos Karampatsas
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom.
| | - Tom Hall
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom
| | - Merryn Voysey
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, United Kingdom
| | - Clara Carreras-Abad
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom
| | - Madeleine Cochet
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom
| | - Laxmee Ramkhelawon
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom
| | - Elisabeth Peregrine
- Department of Obstetrics and Gynaecology, Kingston Hospital NHS Foundation Trust, London, United Kingdom
| | - Nick Andrews
- UK Health Security Agency, London, United Kingdom
| | - Paul T Heath
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom
| | - Kirsty Le Doare
- Centre for Neonatal and Paediatric Infection, St. George's, University of London, London, United Kingdom; Pathogen Immunology Group, UK Health Security Agency, Porton Down, United Kingdom; Makerere University Johns Hopkins University, Kampala, Uganda
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Ling J, Hryckowian AJ. Re-framing the importance of Group B Streptococcus as a gut-resident pathobiont. Infect Immun 2024:e0047823. [PMID: 38436256 DOI: 10.1128/iai.00478-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024] Open
Abstract
Streptococcus agalactiae (Group B Streptococcus, GBS) is a Gram-positive bacterial species that causes disease in humans across the lifespan. While antibiotics are used to mitigate GBS infections, it is evident that antibiotics disrupt human microbiomes (which can predispose people to other diseases later in life), and antibiotic resistance in GBS is on the rise. Taken together, these unintended negative impacts of antibiotics highlight the need for precision approaches for minimizing GBS disease. One possible approach involves selectively depleting GBS in its commensal niches before it can cause disease at other body sites or be transmitted to at-risk individuals. One understudied commensal niche of GBS is the adult gastrointestinal (GI) tract, which may predispose colonization at other body sites in individuals at risk for GBS disease. However, a better understanding of the host-, microbiome-, and GBS-determined variables that dictate GBS GI carriage is needed before precise GI decolonization approaches can be developed. In this review, we synthesize current knowledge of the diverse body sites occupied by GBS as a pathogen and as a commensal. We summarize key molecular factors GBS utilizes to colonize different host-associated niches to inform future efforts to study GBS in the GI tract. We also discuss other GI commensals that are pathogenic in other body sites to emphasize the broader utility of precise de-colonization approaches for mitigating infections by GBS and other bacterial pathogens. Finally, we highlight how GBS treatments could be improved with a more holistic understanding of GBS enabled by continued GI-focused study.
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Affiliation(s)
- Joie Ling
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Healthon, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Andrew J Hryckowian
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Healthon, Madison, Wisconsin, USA
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Bjerkhaug AU, Ramalingham S, Mboizi R, Le Doare K, Klingenberg C. The immunogenicity and safety of Group B Streptococcal maternal vaccines: A systematic review. Vaccine 2024; 42:84-98. [PMID: 38072754 DOI: 10.1016/j.vaccine.2023.11.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 01/01/2024]
Abstract
PURPOSE To systematically review immunogenicity and safety data of maternal group B streptococcal (GBS) vaccines in published clinical trials until July 2023. METHODS EMBASE, MEDLINE, Cochrane Library and clinicaltrial.gov. databases were searched for clinical studies that reported immunogenicity and/or safety of GBS vaccine in non-pregnant adults, pregnant women and infants between 1st of January 1996 to 31st of July 2023. Pairs of reviewers independently selected, data extracted, and assessed the risk of bias of the studies. Discrepancies were resolved by consensus. (PROSPERO CRD42020185213). RESULTS We retrieved 1472 records from the literature search; 20 studies and 6 sub-studies were included, involving 4440 non-pregnant participants and 1325 pregnant women with their newborns. There was a significantly higher IgG Geometric Mean Concentration (GMC) and IgG placental transfer ratios in vaccinated compared to placebo groups, with peak response 4-8 weeks after vaccination. Placental transfer ratio varied from 0.4 to 1.4 across five studies. The different clinical trials used different assays that limited direct comparison. There were no significant differences in the risk of serious adverse events (adjusted OR 0.73; 95 % CI 0.49-1.07), serious adverse events leading to withdrawal (adjusted OR 0.44; 95 % CI 0.13-1.51), and systemic illness or fever (adjusted OR 1.05; 95 % CI 0.26-4.19) between the vaccine and placebo groups. CONCLUSIONS The published clinical trials show significant IgG GMC response in subjects receiving the conjugated capsular polysaccharide and surface subunit protein vaccines compared to placebo. In current clinical trials of experimental GBS maternal vaccines, there have been no observed serious adverse events of special interest directly linked to vaccination.
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Affiliation(s)
- Aline U Bjerkhaug
- Paediatric Research Group, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway; Department of Paediatrics and Adolescence Medicine, University Hospital of North Norway, Tromsø, Norway.
| | - Shouwmika Ramalingham
- Paediatric Research Group, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway
| | - Robert Mboizi
- Makerere University Johns Hopkins University (MU-JHU) Research Collaboration (MUJHU CARE LTD), Kampala, Uganda
| | - Kirsty Le Doare
- Makerere University Johns Hopkins University (MU-JHU) Research Collaboration (MUJHU CARE LTD), Kampala, Uganda; Centre for Neonatal and Paediatric Infection, Maternal and Neonatal Vaccine Immunology Research Group, St Georgés University of London, United Kingdom
| | - Claus Klingenberg
- Paediatric Research Group, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway; Department of Paediatrics and Adolescence Medicine, University Hospital of North Norway, Tromsø, Norway
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Vaz MJ, Dongas S, Ratner AJ. Capsule production promotes Group B Streptococcus intestinal colonization. Microbiol Spectr 2023; 11:e0234923. [PMID: 37732775 PMCID: PMC10655599 DOI: 10.1128/spectrum.02349-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 07/25/2023] [Indexed: 09/22/2023] Open
Abstract
Late-onset disease is the most common clinical presentation of Group B Streptococcus (GBS) infection during infancy, and gastrointestinal (GI) colonization is an important precursor. Previously, we described a murine model of postnatal GBS GI colonization that resulted in sustained colonization and progression to invasive disease. Capsular polysaccharide is an important GBS virulence factor. Vaccines based on a subset of capsular serotypes are in clinical trials. However, little is known regarding the role of specific GBS capsular serotypes in GI colonization. We examined the role of GBS capsule in GI colonization using capsule-producing and acapsular strains derived from GBS strain A909 (serotype Ia) in a murine model. Using isogenic GBS strains differing only in capsular serotypes, we explored the role of specific serotypes in GI colonization by determining competitive indices during cocolonization. We found that GBS A909 colonizes the murine GI tract without causing invasive disease. In monocolonization experiments, there was colonization persistence with the capsule-producing strain (100%) compared to the acapsular mutant strain (13%). In cocolonization experiments, the capsule-producing strain outcompeted its isogenic acapsular mutant, with a geometric mean competitive index of 8, 95% confidence interval (CI) [1.7, 38.9] in the colon at 7 days post-colonization. A909 expressing its native serotype Ia capsule outcompeted an isogenic mutant that expresses serotype III capsule, with a geometric mean competitive index of 2.5, 95% CI [1.2, 5.1] in the colon at 7 days post-colonization. Thus, polysaccharide capsule production enhances GBS GI colonization in vivo. In an A909 genetic background, the production of a serotype Ia capsule provides a competitive advantage over an isogenic strain producing type III capsule. The murine model is a valuable tool to understand the role of GBS capsule types in GI colonization. IMPORTANCE The establishment of GBS intestinal colonization is believed to be a critical precursor to late-onset disease in neonates, which has a significant impact on neurodevelopment outcomes in this population. Our prior work described a murine model of postnatal Group B Streptococcus (GBS) acquisition and invasive disease. Using this model, we explored the importance of GBS polysaccharide capsule production on gastrointestinal colonization. We found that the expression of capsule (compared to isogenic acapsular strains) provides an advantage in intestinal colonization and, importantly, that capsule type Ia has an advantage over capsule type III in a GBS A909 strain background. We speculate that specific serotypes may differ in colonization fitness, which may play a role in serotype distribution in neonatal disease.
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Affiliation(s)
- Michelle J. Vaz
- Department of Pediatrics, NYU School of Medicine, New York, New York, USA
| | - Sophia Dongas
- Department of Pediatrics, NYU School of Medicine, New York, New York, USA
| | - Adam J. Ratner
- Department of Pediatrics, NYU School of Medicine, New York, New York, USA
- Department of Microbiology, NYU School of Medicine, New York, New York, USA
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Madhi SA, Anderson AS, Absalon J, Radley D, Simon R, Jongihlati B, Strehlau R, van Niekerk AM, Izu A, Naidoo N, Kwatra G, Ramsamy Y, Said M, Jones S, Jose L, Fairlie L, Barnabas SL, Newton R, Munson S, Jefferies Z, Pavliakova D, Silmon de Monerri NC, Gomme E, Perez JL, Scott DA, Gruber WC, Jansen KU. Potential for Maternally Administered Vaccine for Infant Group B Streptococcus. N Engl J Med 2023; 389:215-227. [PMID: 37467497 DOI: 10.1056/nejmoa2116045] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
BACKGROUND Natural history studies have correlated serotype-specific anti-capsular polysaccharide (CPS) IgG in newborns with a reduced risk of group B streptococcal disease. A hexavalent CPS-cross-reactive material 197 glycoconjugate vaccine (GBS6) is being developed as a maternal vaccine to prevent invasive group B streptococcus in young infants. METHODS In an ongoing phase 2, placebo-controlled trial involving pregnant women, we assessed the safety and immunogenicity of a single dose of various GBS6 formulations and analyzed maternally transferred anti-CPS antibodies. In a parallel seroepidemiologic study that was conducted in the same population, we assessed serotype-specific anti-CPS IgG concentrations that were associated with a reduced risk of invasive disease among newborns through 89 days of age to define putative protective thresholds. RESULTS Naturally acquired anti-CPS IgG concentrations were associated with a reduced risk of disease among infants in the seroepidemiologic study. IgG thresholds that were determined to be associated with 75 to 95% reductions in the risk of disease were 0.184 to 0.827 μg per milliliter. No GBS6-associated safety signals were observed among the mothers or infants. The incidence of adverse events and of serious adverse events were similar across the trial groups for both mothers and infants; more local reactions were observed in the groups that received GBS6 containing aluminum phosphate. Among the infants, the most common serious adverse events were minor congenital anomalies (umbilical hernia and congenital dermal melanocytosis). GBS6 induced maternal antibody responses to all serotypes, with maternal-to-infant antibody ratios of approximately 0.4 to 1.3, depending on the dose. The percentage of infants with anti-CPS IgG concentrations above 0.184 μg per milliliter varied according to serotype and formulation, with 57 to 97% of the infants having a seroresponse to the most immunogenic formulation. CONCLUSIONS GBS6 elicited anti-CPS antibodies against group B streptococcus in pregnant women that were transferred to infants at levels associated with a reduced risk of invasive group B streptococcal disease. (Funded by Pfizer and the Bill and Melinda Gates Foundation; C1091002 ClinicalTrials.gov number, NCT03765073.).
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Affiliation(s)
- Shabir A Madhi
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Annaliesa S Anderson
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Judith Absalon
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - David Radley
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Raphael Simon
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Babalwa Jongihlati
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Renate Strehlau
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Anika M van Niekerk
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Alane Izu
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Niree Naidoo
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Gaurav Kwatra
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Yogandree Ramsamy
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Mohamed Said
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Stephanie Jones
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Lisa Jose
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Lee Fairlie
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Shaun L Barnabas
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Ryan Newton
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Samantha Munson
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Zahra Jefferies
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Danka Pavliakova
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Natalie C Silmon de Monerri
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Emily Gomme
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - John L Perez
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Daniel A Scott
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - William C Gruber
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
| | - Kathrin U Jansen
- From the South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (S.A.M., R. Strehlau, A.I., G.K., S.J., L.J.), the Department of Paediatrics and Child Health, Faculty of Health Sciences, Rahima Moosa Mother and Child Hospital (R. Strehlau), and Wits RHI, Faculty of Health Sciences, University of the Witwatersrand (L.F.), Johannesburg, the Division of Neonatal Medicine, School of Child and Adolescent Health, Faculty of Health Sciences, University of Cape Town, and Mowbray Maternity Hospital, Cape Town (A.M.N.), the Clinical Neonatology Unit, Prince Mshiyeni Memorial Hospital (N.N.), and the Department of Medical Microbiology, National Health Laboratory Services, Prince Mshiyeni Memorial Hospital and College of Health Sciences, University of KwaZulu-Natal (Y.R.), Durban, the University of Pretoria and the Tshwane Academic Division, National Health Laboratory Services, Pretoria (M.S.), and the Family Center for Research with Ubuntu, Department of Paediatrics and Child Health, Stellenbosch University, Stellenbosch (S.L.B.) - all in South Africa; and Vaccine Research and Development, Pfizer, Pearl River, NY (A.S.A., J.A., D.R., R. Simon, B.J., R.N., S.M., Z.J., D.P., N.C.S.M., E.G., J.L.P., D.A.S., W.C.G., K.U.J.)
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10
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Dangor Z, Seale AC, Baba V, Kwatra G. Early-onset group B streptococcal disease in African countries and maternal vaccination strategies. Front Public Health 2023; 11:1214844. [PMID: 37457277 PMCID: PMC10338870 DOI: 10.3389/fpubh.2023.1214844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 05/31/2023] [Indexed: 07/18/2023] Open
Abstract
Invasive group B streptococcal (GBS) disease is the commonest perinatally-acquired bacterial infection in newborns; the burden is higher in African countries where intrapartum antibiotic prophylaxis strategies are not feasible. In sub-Saharan Africa, almost one in four newborns with GBS early-onset disease will demise, and one in ten survivors have moderate or severe neurodevelopmental impairment. A maternal GBS vaccine to prevent invasive GBS disease in infancy is a pragmatic and cost-effective preventative strategy for Africa. Hexavalent polysaccharide protein conjugate and Alpha family surface protein vaccines are undergoing phase II clinical trials. Vaccine licensure may be facilitated by demonstrating safety and immunological correlates/thresholds suggestive of protection against invasive GBS disease. This will then be followed by phase IV effectiveness studies to assess the burden of GBS vaccine preventable disease, including the effect on all-cause neonatal infections, neonatal deaths and stillbirths.
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Affiliation(s)
- Ziyaad Dangor
- South African Medical Research Council, Vaccines and Infectious Diseases Analytics Unit, University of the Witwatersrand, Johannesburg, South Africa
| | - Anna C. Seale
- Bill and Melinda Gates Foundation, Seattle, WA, United States
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Vuyelwa Baba
- Department of Obstetrics and Gynaecology, University of the Witwatersrand, Johannesburg, South Africa
| | - Gaurav Kwatra
- South African Medical Research Council, Vaccines and Infectious Diseases Analytics Unit, University of the Witwatersrand, Johannesburg, South Africa
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
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11
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Esadze A, Grube CD, Wellnitz S, Singh S, Nguyen HH, Gaylord MA, Zhu A, Gribenko A, Tan CY, Anderson AS, Simon R. Calibration of a serum reference standard for Group B streptococcal polysaccharide conjugate vaccine development using surface plasmon resonance. NPJ Vaccines 2023; 8:71. [PMID: 37208375 DOI: 10.1038/s41541-023-00667-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 04/25/2023] [Indexed: 05/21/2023] Open
Abstract
Group B streptococcus (GBS) is a leading cause of neonatal morbidity and mortality worldwide. Development of a maternal vaccine to protect newborns through placentally transferred antibody is considered feasible based on the well-established relationship between anti-GBS capsular polysaccharide (CPS) IgG levels at birth and reduced risk of neonatal invasive GBS. An accurately calibrated serum reference standard that can be used to measure anti-CPS concentrations is critical for estimation of protective antibody levels across serotypes and potential vaccine performance. For this, precise weight-based measurement of anti-CPS IgG in sera is required. Here, we report an improved approach for determining serum anti-CPS IgG levels using surface plasmon resonance with monoclonal antibody standards, coupled with a direct Luminex-based immunoassay. This technique was used to quantify serotype-specific anti-CPS IgG levels in a human serum reference pool derived from subjects immunized with an investigational six-valent GBS glycoconjugate vaccine.
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Affiliation(s)
- Alexandre Esadze
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA
| | | | - Sabine Wellnitz
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA
| | - Suddham Singh
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA
| | - Ha H Nguyen
- Pfizer Worldwide Research and Development, Pearl River, NY, 10965, USA
| | | | - Aiping Zhu
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA
| | - Alexey Gribenko
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA
| | - Charles Y Tan
- Pfizer Worldwide Research and Development, Collegeville, PA, 19426, USA
| | | | - Raphael Simon
- Pfizer Vaccine Research and Development, Pearl River, NY, 10965, USA.
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12
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Gonzalez-Miro M, Pawlowski A, Lehtonen J, Cao D, Larsson S, Darsley M, Kitson G, Fischer PB, Johansson-Lindbom B. Safety and immunogenicity of the group B streptococcus vaccine AlpN in a placebo-controlled double-blind phase 1 trial. iScience 2023; 26:106261. [PMID: 36915681 PMCID: PMC10005905 DOI: 10.1016/j.isci.2023.106261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 11/28/2022] [Accepted: 02/17/2023] [Indexed: 02/25/2023] Open
Abstract
Group B streptococcus (GBS) is a leading cause of life-threatening neonatal infections and subsets of adverse pregnancy outcomes. Essentially all GBS strains possess one allele of the alpha-like protein (Alp) family. A maternal GBS vaccine, consisting of the fused N-terminal domains of the Alps αC and Rib (GBS-NN), was recently demonstrated to be safe and immunogenic in healthy adult women. To enhance antibody responses to all clinically relevant Alps, a second-generation vaccine has been developed (AlpN), also containing the N-terminal domain of Alp1 and the one shared by Alp2 and Alp3. In this study, the safety and immunogenicity of AlpN is assessed in a randomized, double-blind, placebo-controlled, and parallel-group phase I study, involving 60 healthy non-pregnant women. AlpN is well tolerated and elicits similarly robust and persistent antibody responses against all four Alp-N-terminal domains, resulting in enhanced opsonophagocytic killing of all Alp serotypes covered by the vaccine.
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Affiliation(s)
| | | | - Janne Lehtonen
- Minervax A/S, Ole Maaløes Vej 3, 2200 Copenhagen N, Denmark
| | - Duojia Cao
- Immunology Section, Lund University, BMC D14, Lund, Sweden
| | - Sara Larsson
- Immunology Section, Lund University, BMC D14, Lund, Sweden
| | | | - Geoff Kitson
- Minervax A/S, Ole Maaløes Vej 3, 2200 Copenhagen N, Denmark
| | - Per B Fischer
- Minervax A/S, Ole Maaløes Vej 3, 2200 Copenhagen N, Denmark
| | - Bengt Johansson-Lindbom
- Immunology Section, Lund University, BMC D14, Lund, Sweden.,Minervax A/S, Ole Maaløes Vej 3, 2200 Copenhagen N, Denmark
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13
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Nusman CM, Snoek L, van Leeuwen LM, Dierikx TH, van der Weijden BM, Achten NB, Bijlsma MW, Visser DH, van Houten MA, Bekker V, de Meij TGJ, van Rossem E, Felderhof M, Plötz FB. Group B Streptococcus Early-Onset Disease: New Preventive and Diagnostic Tools to Decrease the Burden of Antibiotic Use. Antibiotics (Basel) 2023; 12:antibiotics12030489. [PMID: 36978356 PMCID: PMC10044457 DOI: 10.3390/antibiotics12030489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/18/2023] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
The difficulty in recognizing early-onset neonatal sepsis (EONS) in a timely manner due to non-specific symptoms and the limitations of diagnostic tests, combined with the risk of serious consequences if EONS is not treated in a timely manner, has resulted in a low threshold for starting empirical antibiotic treatment. New guideline strategies, such as the neonatal sepsis calculator, have been proven to reduce the antibiotic burden related to EONS, but lack sensitivity for detecting EONS. In this review, the potential of novel, targeted preventive and diagnostic methods for EONS is discussed from three different perspectives: maternal, umbilical cord and newborn perspectives. Promising strategies from the maternal perspective include Group B Streptococcus (GBS) prevention, exploring the virulence factors of GBS, maternal immunization and antepartum biomarkers. The diagnostic methods obtained from the umbilical cord are preliminary but promising. Finally, promising fields from the newborn perspective include biomarkers, new microbiological techniques and clinical prediction and monitoring strategies. Consensus on the definition of EONS and the standardization of research on novel diagnostic biomarkers are crucial for future implementation and to reduce current antibiotic overexposure in newborns.
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Affiliation(s)
- Charlotte M. Nusman
- Department of Paediatrics, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Linde Snoek
- Department of Neurology, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Lisanne M. van Leeuwen
- Department of Paediatrics and Department of Vaccin, Infection and Immunology, Spaarne Hospital, Boerhaavelaan 22, 2035 RC Haarlem, The Netherlands
- Department of Paediatrics, Willem Alexander Children Hospital, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Thomas H. Dierikx
- Department of Pediatric Gastroenterology, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Amsterdam Gastroenterology Endocrinology Metabolism Research Institute, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands
| | - Bo M. van der Weijden
- Department of Paediatrics, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Department of Paediatrics, Tergooi Hospital, Rijksstraatweg 1, 1261 AN Blaricum, The Netherlands
| | - Niek B. Achten
- Department of Paediatrics, Erasmus University Medical Centre, Sophia Children’s Hospital, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Merijn W. Bijlsma
- Department of Paediatrics, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Douwe H. Visser
- Department of Neonatology, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Marlies A. van Houten
- Department of Paediatrics and Department of Vaccin, Infection and Immunology, Spaarne Hospital, Boerhaavelaan 22, 2035 RC Haarlem, The Netherlands
| | - Vincent Bekker
- Division of Neonatology, Department of Pediatrics, Willem Alexander Children’s Hospital, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Tim G. J. de Meij
- Department of Pediatric Gastroenterology, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Amsterdam Gastroenterology Endocrinology Metabolism Research Institute, Meibergdreef 69-71, 1105 BK Amsterdam, The Netherlands
| | - Ellen van Rossem
- Department of Paediatrics, Flevo Hospital, Hospitaalweg 1, 1315 RA Almere, The Netherlands
| | - Mariet Felderhof
- Department of Paediatrics, Flevo Hospital, Hospitaalweg 1, 1315 RA Almere, The Netherlands
| | - Frans B. Plötz
- Department of Paediatrics, Emma Children’s Hospital, Amsterdam University Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Department of Paediatrics, Tergooi Hospital, Rijksstraatweg 1, 1261 AN Blaricum, The Netherlands
- Correspondence: ; Tel.: +31-88-753-3664
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14
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Absalon J, Simon R, Radley D, Giardina PC, Koury K, Jansen KU, Anderson AS. Advances towards licensure of a maternal vaccine for the prevention of invasive group B streptococcus disease in infants: a discussion of different approaches. Hum Vaccin Immunother 2022; 18:2037350. [PMID: 35240933 PMCID: PMC9009955 DOI: 10.1080/21645515.2022.2037350] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Group B streptococcus (Streptococcus agalactiae, GBS) is an important cause of life-threatening disease in newborns. Pregnant women colonized with GBS can transmit the bacteria to the developing fetus, as well as to their neonates during or after delivery where infection can lead to sepsis, meningitis, pneumonia, or/and death. While intrapartum antibiotic prophylaxis (IAP) is the standard of care for prevention of invasive GBS disease in some countries, even in such settings a substantial residual burden of disease remains. A GBS vaccine administered during pregnancy could potentially address this important unmet medical need and provide an adjunct or alternative to IAP for the prevention of invasive GBS disease in neonates. A hurdle for vaccine development has been relatively low disease rates making efficacy studies difficult. Given the well-accepted inverse relationship between anti-GBS capsular polysaccharide antibody titers at birth and risk of disease, licensure using serological criteria as a surrogate biomarker represents a promising approach to accelerate the availability of a GBS vaccine.
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Affiliation(s)
- Judith Absalon
- Pfizer Vaccine Research & Development, Pearl River, NY, USA
| | - Raphael Simon
- Pfizer Vaccine Research & Development, Pearl River, NY, USA
| | - David Radley
- Pfizer Vaccine Research & Development, Pearl River, NY, USA
| | | | - Kenneth Koury
- Pfizer Vaccine Research & Development, Pearl River, NY, USA
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15
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Lohrmann F, Hufnagel M, Kunze M, Afshar B, Creti R, Detcheva A, Kozakova J, Rodriguez-Granger J, Sørensen UBS, Margarit I, Maione D, Rinaudo D, Orefici G, Telford J, de la Rosa Fraile M, Kilian M, Efstratiou A, Berner R, Melin P. Neonatal invasive disease caused by Streptococcus agalactiae in Europe: the DEVANI multi-center study. Infection 2022:10.1007/s15010-022-01965-x. [PMID: 36547864 PMCID: PMC9773664 DOI: 10.1007/s15010-022-01965-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022]
Abstract
PURPOSE Group B streptococcus (GBS) remains a leading cause of invasive disease, mainly sepsis and meningitis, in infants < 3 months of age and of mortality among neonates. This study, a major component of the European DEVANI project (Design of a Vaccine Against Neonatal Infections) describes clinical and important microbiological characteristics of neonatal GBS diseases. It quantifies the rate of antenatal screening and intrapartum antibiotic prophylaxis among cases and identifies risk factors associated with an adverse outcome. METHODS Clinical and microbiological data from 153 invasive neonatal cases (82 early-onset [EOD], 71 late-onset disease [LOD] cases) were collected in eight European countries from mid-2008 to end-2010. RESULTS Respiratory distress was the most frequent clinical sign at onset of EOD, while meningitis is found in > 30% of LOD. The study revealed that 59% of mothers of EOD cases had not received antenatal screening, whilst GBS was detected in 48.5% of screened cases. Meningitis was associated with an adverse outcome in LOD cases, while prematurity and the presence of cardiocirculatory symptoms were associated with an adverse outcome in EOD cases. Capsular-polysaccharide type III was the most frequent in both EOD and LOD cases with regional differences in the clonal complex distribution. CONCLUSIONS Standardizing recommendations related to neonatal GBS disease and increasing compliance might improve clinical care and the prevention of GBS EOD. But even full adherence to antenatal screening would miss a relevant number of EOD cases, thus, the most promising prophylactic approach against GBS EOD and LOD would be a vaccine for maternal immunization.
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Affiliation(s)
- Florens Lohrmann
- grid.5963.9Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty, University of Freiburg, Freiburg, Germany ,grid.5963.9Spemann Graduate School of Biology and Medicine (SGBM), Faculty of Biology, University of Freiburg and IMM-PACT Clinician Scientist Program, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Markus Hufnagel
- grid.5963.9Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Mirjam Kunze
- grid.5963.9Department for Gynecology and Obstetrics, University Medical Center, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Baharak Afshar
- grid.515304.60000 0005 0421 4601UK Health Security Agency GB, London, UK
| | - Roberta Creti
- grid.416651.10000 0000 9120 6856Department of Infectious Diseases, Istituto Superiore Di Sanità, Rome, Italy
| | - Antoaneta Detcheva
- grid.419273.a0000 0004 0469 0184National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria
| | - Jana Kozakova
- grid.425485.a0000 0001 2184 1595National Institute of Public Health, Prague, Czech Republic
| | - Javier Rodriguez-Granger
- grid.411380.f0000 0000 8771 3783Servicio Andaluz de Salud, Hospital Universitario Virgen de Las Nieves, Granada, Spain
| | - Uffe B. Skov Sørensen
- grid.7048.b0000 0001 1956 2722Department of Biomedicine, Health, Aarhus University, Aarhus, Denmark
| | | | | | | | - Graziella Orefici
- grid.416651.10000 0000 9120 6856Department of Infectious Diseases, Istituto Superiore Di Sanità, Rome, Italy
| | | | - Manuel de la Rosa Fraile
- grid.411380.f0000 0000 8771 3783Servicio Andaluz de Salud, Hospital Universitario Virgen de Las Nieves, Granada, Spain
| | - Mogens Kilian
- grid.7048.b0000 0001 1956 2722Department of Biomedicine, Health, Aarhus University, Aarhus, Denmark
| | | | - Reinhard Berner
- grid.4488.00000 0001 2111 7257Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Pierrette Melin
- grid.411374.40000 0000 8607 6858Department of Clinical Microbiology, National Reference Center Streptococcus agalactiae, University Hospital Center of Liege, Avenue de L’Hôpital, 1, 4000 Liège 1, Belgique
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16
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Gilbert PB, Isbrucker R, Andrews N, Goldblatt D, Heath PT, Izu A, Madhi SA, Moulton L, Schrag SJ, Shang N, Siber G, Sobanjo-Ter Meulen A. Methodology for a correlate of protection for group B Streptococcus: Report from the Bill & Melinda Gates Foundation workshop held on 10 and 11 February 2021. Vaccine 2022; 40:4283-4291. [PMID: 35779963 DOI: 10.1016/j.vaccine.2022.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/05/2022] [Indexed: 01/19/2023]
Abstract
Worldwide, childhood mortality has declined significantly, with improvements in hygiene and vaccinations against common childhood illnesses, yet newborn mortality remains high. Group B Streptococcus (GBS) disease significantly contributes to newborn mortality and is the leading cause of meningitis in infants. Many years of research have demonstrated the potential for maternal vaccination against GBS to confer protection to the infant, and at least three vaccine candidates are currently undergoing clinical trials. Given the relatively low disease incidence, any clinical vaccine efficacy study would need to include at least 40,000 to 60,000 participants. Therefore, a path to vaccine licensure based on a correlate of protection (CoP) would be the preferred route, with post-approval effectiveness studies demonstrating vaccine impact on reduction of disease burden likely to be required as part of conditional marketing approval. This workshop, hosted by the Bill & Melinda Gates Foundation on 10 and 11 February 2021, discussed considerations and potential statistical methodologies for establishing a CoP for GBS disease. Consensus was reached that an antibody marker with global threshold predictive of a high level of vaccine protection would be most beneficial for licensure assessments. IgG binding antibody in cord blood would likely serve as the CoP, with additional studies needed to confirm a high correlation with functional antibody and to demonstrate comparable kinetics of natural versus vaccine-induced antibody. Common analyses of ongoing seroepidemiological studies include estimation of absolute and relative disease risk as a function of infant antibody concentration, with adjustment for confounders of the impact of antibody concentration on infant GBS disease including gestational age and maternal age. Estimation of an antibody concentration threshold indicative of high protection should build in margin for uncertainties from sources including unmeasured confounders, imperfect causal mediation, and variability in point and confidence interval estimates across regions and/or serotypes.
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Affiliation(s)
- Peter B Gilbert
- Vaccine and Infectious Disease and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center and Department of Biostatistics, University of Washington, USA
| | | | - Nick Andrews
- UK Health Security Agency, Colindale, London, UK
| | - David Goldblatt
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Paul T Heath
- Vaccine Institute, St George's, University of London, London, UK
| | - Alane Izu
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; African Leadership in Vaccinology Expertise, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Shabir A Madhi
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; African Leadership in Vaccinology Expertise, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Lawrence Moulton
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Stephanie J Schrag
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Nong Shang
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
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17
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Haeusler IL, Daniel O, Isitt C, Watts R, Cantrell L, Feng S, Cochet M, Salloum M, Ikram S, Hayter E, Lim S, Hall T, Athaide S, Cosgrove CA, Tregoning JS, Le Doare K. Group B Streptococcus (GBS) colonisation is dynamic over time, whilst GBS capsular polysaccharides-specific antibody remains stable. Clin Exp Immunol 2022; 209:188-200. [PMID: 35802786 PMCID: PMC9390841 DOI: 10.1093/cei/uxac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/08/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022] Open
Abstract
Group B Streptococcus (GBS) is a leading cause of adverse pregnancy outcomes due to invasive infection. This study investigated longitudinal variation in GBS rectovaginal colonization, serum and vaginal GBS capsular polysaccharide (CPS)-specific antibody levels. Non-pregnant women were recruited in the UK and were sampled every 2 weeks over a 12-week period. GBS isolates were taken from recto-vaginal swabs and serotyped by polymerase chain reaction. Serum and vaginal immunoglobulin G (IgG) and nasal immunoglobulin A (IgA) specific to CPS were measured by Luminex, and total IgG/A by ELISA. Seventy women were enrolled, of median age 26. Out of the 66 participants who completed at least three visits: 14/47 (29.8%) women that were GBS negative at screening became positive in follow-up visits and 16/19 (84.2%) women who were GBS positive at screening became negative. There was 50% probability of becoming negative 36 days after the first positive swab. The rate of detectable GBS carriage fluctuated over time, although serum, vaginal, and nasal CPS-specific antibody levels remained constant. Levels of CPS-specific antibodies were higher in the serum of individuals colonized with GBS than in non-colonized, but similar in the vaginal and nasal mucosa. We found correlations between antibody levels in serum and the vaginal and nasal mucosa. Our study demonstrates the feasibility of elution methods to retrieve vaginal and nasal antibodies, and the optimization of immunoassays to measure GBS-CPS-specific antibodies. The difference between the dynamics of colonization and antibody response is interesting and further investigation is required for vaccine development.
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Affiliation(s)
- I L Haeusler
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - O Daniel
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - C Isitt
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - R Watts
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - L Cantrell
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford
| | - S Feng
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford
| | - M Cochet
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - M Salloum
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom.,UnivLyon, Claude Bernard University Lyon I, France
| | - S Ikram
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - E Hayter
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - S Lim
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - T Hall
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom
| | - S Athaide
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - C A Cosgrove
- St George's University of London, The Vaccine Institute, London, United Kingdom
| | - J S Tregoning
- Imperial College London, Department of Infectious Disease, London, United Kingdom
| | - K Le Doare
- St George's University of London, Paediatric Infectious Diseases Research Group, London, United Kingdom.,Makerere University John Hopkins Research Collaboration, Kampala, Uganda.,Pathogen Immunology Group, United Kingdom Health Security Agency, Porton Down, United Kingdom
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18
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Izu A, Kwatra G, Madhi SA, Rigat F. Estimation of invasive Group B Streptococcus disease risk in young infants from case-control serological studies. BMC Med Res Methodol 2022; 22:85. [PMID: 35350991 PMCID: PMC8961496 DOI: 10.1186/s12874-022-01529-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 01/20/2022] [Indexed: 11/12/2022] Open
Abstract
Background Group B Streptococcus (GBS) infections are a major cause of invasive disease (IGbsD) in young infants and cause miscarriage and stillbirths. Immunization of pregnant women against GBS in addition to intrapartum antibiotic prophylaxis could prevent disease. Establishing accurate serological markers of protection against IGbsD could enable use of efficient clinical trial designs for vaccine development and licensure, without needing to undertake efficacy trials in prohibitively large number of mother-infant dyads. The association of maternal naturally acquired serotype-specific anti-capsular antibodies (IgG) against serotype-specific IGbsD in their infants has been studied in case-control studies. The statistical models used so far to estimate IGbsD risk from these case-control studies assumed that the antibody concentrations measured sharing the same disease status are sampled from the same population, not allowing for differences between mothers colonised by GBS and mothers also potentially infected (e.g urinary tract infection or chorioamnionitis) by GBS during pregnancy. This distinction is relevant as infants born from infected mothers with occult medical illness may be exposed to GBS prior to the mother developing antibodies measured in maternal or infant sera. Methods Unsupervised mixture model averaging (MMA) is proposed and applied here to accurately estimate infant IGbsD risk from case-control study data in presence or absence of antibody concentration subgroups potentially associated to maternal GBS carriage or infection. MMA estimators are compared to non-parametric disease risk estimators in simulation studies and by analysis of two published GBS case-control studies. Results MMA provides more accurate relative risk estimates under a broad range of data simulation scenarios and more accurate absolute disease risk estimates when the proportion of IGbsD cases with high antibody levels is not ignorable. MMA estimates of the relative and absolute disease risk curves are more amenable to clinical interpretation compared to non-parametric estimates with no detectable overfitting of the data. Antibody concentration thresholds predictive of protection from infant IGbsD estimated by MMA from maternal and infant sera are consistent with non-parametric estimates. Conclusions MMA is a flexible and robust method for design, accurate analysis and clinical interpretation of case-control studies estimating relative and absolute IGbsD risk from antibody concentrations measured at or after birth.
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Affiliation(s)
- Alane Izu
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa. .,Department of Science and Innovation/National Research Foundation South African Research Chair Initiative in Vaccine Preventable Diseases Unit, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa.
| | - Gaurav Kwatra
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa.,Department of Science and Innovation/National Research Foundation South African Research Chair Initiative in Vaccine Preventable Diseases Unit, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Shabir A Madhi
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa.,Department of Science and Innovation/National Research Foundation South African Research Chair Initiative in Vaccine Preventable Diseases Unit, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Fabio Rigat
- Statistics and Decision Sciences, Janssen Pharmaceuticals R & D, High Wycombe, United Kingdom.
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19
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Dammann AN, Chamby AB, Gonzalez FJ, Sharp ME, Flores K, Shahi I, Dongas S, Hooven TA, Ratner AJ. Group B Streptococcus capsular serotype alters vaginal colonization fitness. J Infect Dis 2021; 225:1896-1904. [PMID: 34788438 DOI: 10.1093/infdis/jiab559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 11/02/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Group B Streptococcus (GBS) remains a leading cause of infant morbidity and mortality. A candidate vaccine targets six GBS serotypes, offering a potential alternative to intrapartum antibiotic prophylaxis to reduce disease burden. However, our understanding of the contributions of specific capsule types to GBS colonization and disease remains limited. METHODS Using allelic exchange, we generated isogenic GBS strains differing only in the serotype-determining region in two genetic backgrounds, including the hypervirulent clonal complex (CC) 17. Using a murine model of vaginal co-colonization, we evaluated the roles of the presence of capsule and of expression of specific capsular types in GBS vaginal colonization fitness independent of other genetic factors. RESULTS Encapsulated wild-type strains COH1 (CC17, serotype III) and A909 (non-CC17, serotype Ia), outcompeted isogenic acapsular mutants in murine vaginal co-colonization. COH1 wild-type outcompeted A909. Notably, expression of type Ia capsule conferred an advantage over type III capsule in both genetic backgrounds. CONCLUSIONS Specific capsule types may provide an advantage in GBS vaginal colonization in vivo. However, success of certain GBS lineages, including CC17, likely involves both capsule and non-capsule genetic elements. Capsule switching in GBS, a potential outcome of conjugate vaccine programs, may alter colonization fitness or pathogenesis.
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Affiliation(s)
- Allison N Dammann
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Anna B Chamby
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Francisco J Gonzalez
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Molly E Sharp
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Karina Flores
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Ifrah Shahi
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Sophia Dongas
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Thomas A Hooven
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Richard King Mellon Institute for Pediatric Research, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Adam J Ratner
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA.,Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
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20
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Maternal vaccination with a type-III glycoconjugate protects mouse neonates against Group B Streptococcus intranasal infection. Sci Rep 2021; 11:21384. [PMID: 34725414 PMCID: PMC8560876 DOI: 10.1038/s41598-021-00941-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 10/12/2021] [Indexed: 11/15/2022] Open
Abstract
Group B Streptococcus (GBS) is generally an asymptomatic colonizer of human mucosa but it occasionally infects pregnant women and neonates through vertical transmission, causing disease during the first weeks of life with frequent and severe complications. Preclinical studies have shown that maternal vaccination with polysaccharide-based vaccines protects mothers and offspring from GBS mucosal colonization and consecutive infection. In these models, bacteria were inoculated in mouse either intravaginally in the last trimester of pregnancy or systemically in pups. Here, we investigated whether maternal vaccination with glycoconjugate vaccines may also prevent GBS-mediated colonization and disease in neonates using an infection route that more closely mimics inhalation or ingestion of bacteria during human delivery. To address this point, mice aged less than two days were intranasally challenged with epidemiologically relevant GBS strains. Bacteria were found to colonize nose and intestine, reaching in some cases lungs and blood during the first days of life. Bacteria were also found in vagina of a fraction of colonized female mice within the first month of life. GBS-specific IgG induced by maternal vaccination with a glycoconjugate vaccine formulation were found in blood and mucosal tissues of newborns. Finally, when intranasally challenged with GBS serotype III strains, pups delivered by vaccinated mothers were partially protected against mucosal colonization and deeper infection.
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21
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Development and Validation of Enzyme-Linked Immunosorbent Assay for Group B Streptococcal Polysaccharide Vaccine. Vaccines (Basel) 2021; 9:vaccines9060545. [PMID: 34064299 PMCID: PMC8224333 DOI: 10.3390/vaccines9060545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 11/20/2022] Open
Abstract
Streptococcus agalactiae (group B Streptococcus, GBS) is a leading cause of neonatal sepsis and meningitis in infants. Limitations of prenatal GBS screening and intrapartum antibiotic prophylaxis render developing GBS vaccines a high priority. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) for the practical and large-scale evaluation of GBS capsular polysaccharide (PS) vaccine immunogenicity against three main serotypes, Ia, III, and V. GBS-ELISA was developed and subsequently validated using a standardized curve-fitting four-parameter logistic method. Specificity was measured using adsorption of serum with homologous and heterologous PS. Homologous adsorption showed a ≥75% inhibition of all three serotypes, whereas with heterologous PS, IgG GBS-ELISA inhibited only ≤25% of serotypes III and V. However, with serotype Ia, IgG antibody levels decreased by >50%, even after adsorption with heterologous PS (III or V). In comparison, the inhibition opsonophagocytic killing assay (OPA) of serotypes Ia GBS exhibited a reduction in opsonophagocytic activity of only 20% and 1.1% for serotypes III and V GBS, respectively. The precision of the GBS-ELISA was assessed in five independent experiments using four serum samples. The coefficient of variation was <5% for all three serotypes. This standardized GBS-ELISA would be useful for GBS vaccine development and its evaluation.
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22
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Lohrmann F, Berg A, Wicker E, Imm A, Krause G, Zürn K, Berner R, Hufnagel M, Lander F. Prevalence of Capsular Serotype, Pilus Island Distribution, and Antibiotic Resistance in Pediatric and Adult Invasive Group B Streptococcus Isolates: Data From a Nationwide Prospective Surveillance Study in Germany. Pediatr Infect Dis J 2021; 40:76-82. [PMID: 33201062 DOI: 10.1097/inf.0000000000002943] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
For neonates, group B Streptococcus is life threatening. Current prevention strategies remain insufficient, especially for cases of late-onset sepsis, where intrapartum antibiotic prophylaxis has demonstrated no benefit. One promising approach is the vaccination of pregnant women, which offers protective immunity via transplacental transmission of neutralizing antibodies. Our nationwide, prospective surveillance study aimed to characterize the prevalence of pilus antigen, capsular polysaccharide serotypes, and antibiotic resistance from invasive GBS infections in neonates and compare these results with those from children and adults in Germany. Our study includes 173 neonatal isolates of a total of 450 reported cases during the study period (incidence: 0.34/1000 live births), in addition to 2 pediatric and 803 adult isolates. The comparison between neonatal and adult isolates reveals age-dependent differences in capsular serotype and pilus type distribution and differences in antibiotic resistance patterns.
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Affiliation(s)
- Florens Lohrmann
- From the Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty
- Spemann Graduate School of Biology and Medicine (SGBM), Faculty of Biology
- IMM-PACT Clinician Scientist Program, Faculty of Medicine, Freiburg, Germany
| | - Angela Berg
- From the Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty
- Department for Gynecology and Obstetrics, DRK Hospital Westend, Berlin, Germany
| | - Esther Wicker
- Department of Anaesthesiology and Operative Intensive Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Anita Imm
- From the Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty
| | - Gérard Krause
- Epidemiology Department, Helmholtz Centre for Infection Research, Braunschweig, Germany
- Institute for Infectious Disease Epidemiology, TWINCORE, Hannover, Germany
- Translational Infrastructure Epidemiology, German Centre for Infection Research (DZIF), Braunschweig, Germany
| | - Katharina Zürn
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Reinhard Berner
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Markus Hufnagel
- From the Department of Pediatrics and Adolescent Medicine, University Medical Center, Medical Faculty
| | - Fabian Lander
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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23
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Madhi SA, Izu A, Kwatra G, Jones S, Dangor Z, Wadula J, Moultrie A, Adam Y, Pu W, Henry O, Briner C, Cutland CL. Association of Group B streptococcus serum serotype-specific anti-capsular IgG concentration and risk reduction for invasive Group B streptococcus disease in South African infants: an observational birth-cohort, matched case-control study. Clin Infect Dis 2020; 73:e1170-e1180. [PMID: 33341870 DOI: 10.1093/cid/ciaa1873] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Licensure of a Group B streptococcus (GBS) polysaccharide-protein conjugate vaccine for protecting infants against invasive GBS disease (IGbsD) will likely need to be based on demonstrating vaccine safety in pregnant women, and benchmarking immunogenicity against a serological threshold associated with risk reduction of IGbsD. We investigated the association between naturally-derived GBS serotype-Ia and III IgG and risk reduction of IGbsD in infants' ≤90 days of age. METHODS In a matched case-control study (ClinicalTrials.gov NCT02215226), IGbsD cases were identified from a cohort of 38,233 mother-newborn dyads. Mothers colonized vaginally with serotype-Ia or III at birth, and their healthy infants were eligible as matched controls. GBS serotype-specific anti-capsular IgG was measured on maternal and cord blood/infant sera by multiplex Luminex assay; and the IgG threshold associated with 90% risk reduction of IGbsD derived by estimating absolute disease risk. RESULTS In infants born ≥34 weeks gestational age, cord-blood IgG geometric mean concentrations (GMC) were lower in cases than controls for serotype-Ia (0.05 vs. 0.50µg/ml; p=0.004) and III (0.20 vs. 0.38µg/ml; p=0.078). Cord-blood IgG concentration ≥1.04 and ≥1.53µg/ml were associated with 90% risk reduction of serotype-Ia and III IGbsD, respectively. The maternal sera IgG threshold associated with 90% risk reduction was ≥2.31 and ≥3.41µg/ml for serotype-Ia and III, respectively. CONCLUSIONS The threshold associated with a reduced risk for serotype-Ia and III IGbsD identified on infant sera supports the case for licensure of a GBS polysaccharide-protein conjugate vaccine based on immunogenicity evaluation benchmarked against the defined thresholds.
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Affiliation(s)
- Shabir A Madhi
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Alane Izu
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Gaurav Kwatra
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Stephanie Jones
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Ziyaad Dangor
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa.,Department of Paediatrics, Chris Hani Baragwanath Academic Hospital, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jeanette Wadula
- National Health Laboratory Services, Department of Anatomical Pathology, School of Pathology, University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
| | - Andrew Moultrie
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Yasmin Adam
- Department of Obstetrics and Gynecology, Chris Hani-Baragwanath Academic Hospital, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | | | - Carmen Briner
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
| | - Clare L Cutland
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit (VIDA), University of the Witwatersrand, Faculty of Health Science Johannesburg, South Africa.,Department of Science/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Faculty of Health Science, Johannesburg, South Africa
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24
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Singh T, Otero CE, Li K, Valencia SM, Nelson AN, Permar SR. Vaccines for Perinatal and Congenital Infections-How Close Are We? Front Pediatr 2020; 8:569. [PMID: 33384972 PMCID: PMC7769834 DOI: 10.3389/fped.2020.00569] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 08/04/2020] [Indexed: 12/26/2022] Open
Abstract
Congenital and perinatal infections are transmitted from mother to infant during pregnancy across the placenta or during delivery. These infections not only cause pregnancy complications and still birth, but also result in an array of pediatric morbidities caused by physical deformities, neurodevelopmental delays, and impaired vision, mobility and hearing. Due to the burden of these conditions, congenital and perinatal infections may result in lifelong disability and profoundly impact an individual's ability to live to their fullest capacity. While there are vaccines to prevent congenital and perinatal rubella, varicella, and hepatitis B infections, many more are currently in development at various stages of progress. The spectrum of our efforts to understand and address these infections includes observational studies of natural history of disease, epidemiological evaluation of risk factors, immunogen design, preclinical research of protective immunity in animal models, and evaluation of promising candidates in vaccine trials. In this review we summarize this progress in vaccine development research for Cytomegalovirus, Group B Streptococcus, Herpes simplex virus, Human Immunodeficiency Virus, Toxoplasma, Syphilis, and Zika virus congenital and perinatal infections. We then synthesize this evidence to examine how close we are to developing a vaccine for these infections, and highlight areas where research is still needed.
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Affiliation(s)
- Tulika Singh
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, United States
| | - Claire E. Otero
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
| | - Katherine Li
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
| | - Sarah M. Valencia
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
| | - Ashley N. Nelson
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
| | - Sallie R. Permar
- Duke University Medical Center, Duke Human Vaccine Institute, Durham, NC, United States
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, United States
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25
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Absalon J, Segall N, Block SL, Center KJ, Scully IL, Giardina PC, Peterson J, Watson WJ, Gruber WC, Jansen KU, Peng Y, Munson S, Pavliakova D, Scott DA, Anderson AS. Safety and immunogenicity of a novel hexavalent group B streptococcus conjugate vaccine in healthy, non-pregnant adults: a phase 1/2, randomised, placebo-controlled, observer-blinded, dose-escalation trial. THE LANCET. INFECTIOUS DISEASES 2020; 21:263-274. [PMID: 32891191 DOI: 10.1016/s1473-3099(20)30478-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/13/2020] [Accepted: 04/23/2020] [Indexed: 12/18/2022]
Abstract
BACKGROUND Group B streptococcus (GBS) is a major cause of invasive disease in young infants. Infants born to women with sufficient pre-existing anti-GBS capsular IgG antibodies are at reduced risk of GBS disease, making maternal immunisation a potential strategy for prevention. We aimed to assess the safety and immunogenicity of a novel hexavalent (serotypes Ia, Ib, II, III, IV, and V) GBS conjugate vaccine (GBS6). METHODS This phase 1/2, placebo-controlled, observer-blinded, dose-escalation trial, was done at four clinical research centres in the USA (Kentucky, Georgia, and two sites in Utah). Healthy, non-pregnant adults aged 18-49 years were randomly assigned using an interactive, web-based response technology system. Within each dose group (low, medium, or high), participants in sentinel cohorts were randomly assigned 2:2:1 and expanded cohort participants were randomly assigned 4:4:1 to receive GBS6 with aluminium phosphate (AlPO4), GBS6 without AlPO4, or placebo (saline control). One 0·5 mL dose of either saline placebo or 5 μg capsular polysaccharide per serotype in the low-dose group, 10 μg capsular polysaccharide per serotype in the medium-dose group, or 20 μg capsular polysaccharide per serotype in the high-dose group was administered by intramuscular injection into the deltoid muscle on day 1. The primary outcome was safety up to 6 months after vaccination, including the proportion of sentinel cohort participants with clinical laboratory abnormalities at 1 week, the proportion of all participants reporting solicited local reactions, systemic events, or use of antipyretic or pain medication within 14 days, adverse events up to 1 month, and medically attended or serious adverse events up to 6 months. The secondary outcome was GBS immunogenicity (serotype-specific IgG geometric mean concentrations at 1 month). This study is registered with ClinicalTrials.gov, NCT03170609. FINDINGS Between June 5, 2017, and June 25, 2018, 365 participants were randomly assigned and 364 (52 in each dose group) were vaccinated and included in the safety analysis. Unsolicited adverse events were reported by 15 (29%) participants in the 5 μg with AlPO4 group, 13 (25%) in the 5 μg without AlPO4 group, 22 (42%) in the 10 μg with AlPO4 group, 12 (23%) in the 10 μg without AlPO4 group, 25 (48%) in the 20 μg with AlPO4 group, 21 (40%) in the 20 μg without AlPO4 group, and 20 (38%) in the placebo group. The most common unsolicited adverse events were in the system organ class of infections and infestations in any dose or formulation of GBS6 (ranging from six [12%] in the 10 μg without AlPO4 group to 15 [29%] in the 20 μg with AlPO4 group and placebo group). Three participants reported at least one serious adverse event during the study, one each in the 5 μg GBS6 with AlPO4 group (diabetic ketoacidosis, two events; resolved), 10 μg GBS6 with AlPO4 group (died by suicide), and 20 μg GBS6 with AlPO4 group (metrorrhagia; resolved). None of these serious adverse events were considered related to the vaccine. 11 of the 365 participants were excluded from the evaluable immunogenicity population, including one participant who did not receive the vaccine, and ten who at 1 month after vaccination were withdrawn for various reasons. GBS serotype-specific IgG geometric mean concentrations increased by 1 week after vaccination for all GBS6 groups, peaked at 2 weeks, stabilised by 1 month, and declined gradually but remained higher than placebo at 6 months. INTERPRETATION GBS6 was well tolerated in healthy adults and elicited robust immune responses for all dose levels and formulations that persisted 6 months after vaccination. This study supports further evaluation of GBS6 in pregnant women. FUNDING Pfizer.
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Affiliation(s)
- Judith Absalon
- Vaccine Research and Development, Pfizer, Pearl River, NY, USA.
| | | | - Stan L Block
- Kentucky Pediatric/Adult Research, Bardstown, KY, USA
| | | | - Ingrid L Scully
- Vaccine Research and Development, Pfizer, Pearl River, NY, USA
| | | | | | - Wendy J Watson
- Vaccine Research and Development, Pfizer, Collegeville, PA, USA
| | | | | | - Yahong Peng
- Vaccine Research and Development, Pfizer, Collegeville, PA, USA
| | - Samantha Munson
- Vaccine Research and Development, Pfizer, Collegeville, PA, USA
| | | | - Daniel A Scott
- Vaccine Research and Development, Pfizer, Collegeville, PA, USA
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Berner R. Group B streptococcus vaccines: one step further. THE LANCET. INFECTIOUS DISEASES 2020; 21:158-160. [PMID: 32891192 PMCID: PMC7470735 DOI: 10.1016/s1473-3099(20)30451-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 11/04/2022]
Affiliation(s)
- Reinhard Berner
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden 01307, Germany.
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27
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Swamy GK, Metz TD, Edwards KM, Soper DE, Beigi RH, Campbell JD, Grassano L, Buffi G, Dreisbach A, Margarit I, Karsten A, Henry O, Lattanzi M, Bebia Z. Safety and immunogenicity of an investigational maternal trivalent group B streptococcus vaccine in pregnant women and their infants: Results from a randomized placebo-controlled phase II trial. Vaccine 2020; 38:6930-6940. [PMID: 32883555 DOI: 10.1016/j.vaccine.2020.08.056] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 01/31/2023]
Abstract
BACKGROUND This study evaluated the safety and immunogenicity of an investigational trivalent group B streptococcus (GBS) vaccine in US pregnant women, transplacental serotype-specific antibody transfer and persistence in infants, and serotype-specific antibodies in breast milk. METHODS This randomized, observer-blind, placebo-controlled trial administered one dose of trivalent GBS vaccine (n = 49) or placebo (n = 26) to healthy pregnant 18-40-year-old women at 240/7-346/7 weeks' gestation. Women were enrolled from March 2014 to August 2015. Safety follow-up continued through postpartum day 180. Primary immunogenicity objectives were to evaluate serotype Ia/Ib/III-specific immunoglobulin G (IgG) levels in sera from women on day 1 (pre-vaccination), day 31, delivery and postpartum days 42 and 90, and from infants at birth (cord blood), days 42 and 90. Antibody transfer ratios (cord blood/maternal sera at delivery) and serotype-specific secretory immunoglobulin A (sIgA) and IgG in breast milk after delivery and on postpartum days 42 and 90 were evaluated. The planned sample size was not based on statistical assumptions for this descriptive study. RESULTS Baseline characteristics were similar between groups. Serious adverse events were reported for 16% of GBS-vaccinated women and 15% of their infants, and 15% of placebo recipients and 12% of their infants; none were fatal or deemed vaccine-related. Serotype-specific IgG geometric mean concentrations (GMCs) were 13-23-fold higher in vaccine vs placebo recipients on day 31 and persisted until postpartum day 90. Median antibody concentrations were substantially higher in women with detectable pre-vaccination antibody concentrations. Antibody transfer ratios in the vaccine group were 0.62-0.82. Infant IgG GMCs and breast milk sIgA GMCs were higher in the vaccine vs the placebo group at all timepoints. CONCLUSIONS Maternal immunization with the trivalent GBS vaccine in US women had a favorable safety profile, elicited antibodies that were transplacentally transferred and persisted in infants for a minimum of 3 months. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov, NCT02046148.
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Affiliation(s)
- Geeta K Swamy
- Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, NC, USA.
| | - Torri D Metz
- Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, CO, USA.
| | - Kathryn M Edwards
- Vanderbilt Vaccine Research Program, Vanderbilt University, Nashville, TN, USA.
| | - David E Soper
- Medical University of South Carolina, Charleston, SC, USA.
| | - Richard H Beigi
- UPMC Magee-Women's Hospital, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - James D Campbell
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, USA.
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Hillier SL, Ferrieri P, Edwards MS, Ewell M, Ferris D, Fine P, Carey V, Meyn L, Hoagland D, Kasper DL, Paoletti LC, Hill H, Baker CJ. A Phase 2, Randomized, Control Trial of Group B Streptococcus (GBS) Type III Capsular Polysaccharide-tetanus Toxoid (GBS III-TT) Vaccine to Prevent Vaginal Colonization With GBS III. Clin Infect Dis 2020; 68:2079-2086. [PMID: 30281066 DOI: 10.1093/cid/ciy838] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/28/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Group B Streptococcus (GBS) frequently colonizes pregnant women and can cause sepsis and meningitis in young infants. If colonization was prevented through maternal immunization, a reduction in perinatal GBS disease might be possible. A GBS type III capsular polysaccharide (CPS)-tetanus toxoid conjugate (III-TT) vaccine was evaluated for safety and efficacy in preventing acquisition of GBS colonization. METHODS Healthy, nonpregnant women aged 18-40 years and screened to be GBS III vaginal and rectal culture negative were randomized to receive III-TT conjugate or tetanus diphtheria toxoid vaccine in a multicenter, observer-blinded trial. GBS vaginal and rectal cultures and blood were obtained bimonthly over 18 months. Serum concentrations of GBS III CPS-specific antibodies were determined using enzyme-linked immunosorbent assay. RESULTS Among 1525 women screened, 650 were eligible for the intent-to-treat analysis. For time to first acquisition of vaginal GBS III, vaccine efficacy was 36% (95% confidence interval [CI], 1%-58%; P = .044), and for first rectal acquisition efficacy was 43% (95% CI, 11% to 63%; P = .014). Two months post-immunization, geometric mean concentrations of serum GBS type III CPS-specific immunoglobulin G were 12.6 µg/mL (95% CI, 9.95 to 15.81) in GBS III-TT recipients, representing a 4-fold increase from baseline in 95% of women, which persisted. Both vaccines were well tolerated. CONCLUSIONS GBS CPS III-TT conjugate vaccine significantly delayed acquisition of vaginal and rectal GBS III colonization. In addition to its use for maternal immunization to passively protect infants with maternally derived antibodies, a multivalent vaccine might also serve to reduce fetal and neonatal exposure to GBS. CLINICAL TRIALS REGISTRATION NCT00128219.
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Affiliation(s)
- Sharon L Hillier
- University of Pittsburgh School of Medicine, Magee-Womens Hospital, Pennsylvania
| | - Patricia Ferrieri
- Department of Laboratory Medicine and Pathology and Pediatrics, University of Minnesota Medical School, Minneapolis
| | - Morven S Edwards
- Baylor College of Medicine, Department of Pediatrics, Feigin Center, Houston, Texas
| | | | | | - Paul Fine
- Planned Parenthood Gulf Coast, Houston, Texas
| | - Vincent Carey
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Leslie Meyn
- University of Pittsburgh School of Medicine, Magee-Womens Hospital, Pennsylvania
| | | | - Dennis L Kasper
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts
| | - Lawrence C Paoletti
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts
| | | | - Carol J Baker
- Divsion of Infectious Disease, Department of Pediatrics, University of Texas Health Science Center McGovern Medical School, Houston
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Villamor E, Norman M, Johansson S, Cnattingius S. Maternal Obesity and Risk of Early-onset Neonatal Bacterial Sepsis: Nationwide Cohort and Sibling-controlled Studies. Clin Infect Dis 2020; 73:e2656-e2664. [PMID: 32770206 DOI: 10.1093/cid/ciaa783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/11/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Maternal overweight and obesity are related to risks of pregnancy and delivery complications that, in turn, are associated with newborn infections. We examined the associations between early pregnancy body mass index (BMI; kg/m2) and risk of early-onset neonatal bacterial sepsis (EOS). METHODS We conducted a nationwide population-based retrospective cohort study of 1 971 346 live singleton infants born in Sweden between 1997 and 2016. Outcome was a culture-confirmed EOS diagnosis. We estimated hazard ratios (HR) of EOS according to BMI using proportional hazard models, and identified potential mediators. Among term infants, we conducted sibling-controlled analyses. RESULTS EOS risk per 1000 live births was 1.48; 0.76 in term and 15.52 in preterm infants. Compared with infants of normal-weight mothers (BMI, 18.5-24.9), the adjusted HR (95% confidence interval [CI]) of EOS for BMI categories <18.5, 25.0-29.9, 30.0-34.9, 35.0-39.9, and ≥40.0 were, respectively, 1.07 (.83-1.40), 1.19 (1.08-1.32), 1.70 (1.49-1.94), 2.11 (1.73-2.58), and 2.50 (1.86-3.38). Maternal overweight and obesity increased the risk of EOS by group B Streptococcus, Staphylococcus aureus, and Escherichia coli. Half of the association was mediated through preeclampsia, cesarean section delivery, and preterm delivery. A dose-response association was consistently apparent in term infants only. In sibling-controlled analyses, every kilogram per meter squared interpregnancy BMI change was associated with a mean 8.3% increase in EOS risk (95% CI, 1.7%-15.3%; P = .01). CONCLUSIONS Risk of EOS increases with maternal overweight and obesity severity, particularly in term infants.
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Affiliation(s)
- Eduardo Villamor
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
| | - Mikael Norman
- Department of Clinical Science, Intervention, and Technology, Division of Pediatrics, Karolinska Institutet, Stockholm, Sweden
| | - Stefan Johansson
- Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm, Sweden.,Division of Clinical Epidemiology, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
| | - Sven Cnattingius
- Division of Clinical Epidemiology, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
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30
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Carreras-Abad C, Ramkhelawon L, Heath PT, Le Doare K. A Vaccine Against Group B Streptococcus: Recent Advances. Infect Drug Resist 2020; 13:1263-1272. [PMID: 32425562 PMCID: PMC7196769 DOI: 10.2147/idr.s203454] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/10/2020] [Indexed: 01/12/2023] Open
Abstract
Group B streptococcus (GBS) causes a high burden of neonatal and infant disease globally. Implementing a vaccine for pregnant women is a promising strategy to prevent neonatal and infant GBS disease and has been identified as a priority by the World Health Organisation (WHO). GBS serotype-specific polysaccharide – protein conjugate vaccines are at advanced stages of development, but a large number of participants would be required to undertake Phase III clinical efficacy trials. Efforts are therefore currently focused on establishing serocorrelates of protection in natural immunity studies as an alternative pathway for licensure of a GBS vaccine, followed by Phase IV studies to evaluate safety and effectiveness. Protein vaccines are in earlier stages of development but are highly promising as they might confer protection irrespective of serotype. Further epidemiological, immunological and health economic studies are required to enable the vaccine to reach its target population as soon as possible.
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Affiliation(s)
- Clara Carreras-Abad
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK.,Department of Paediatrics, Obstetrics and Gynecology and Preventive Medicine and Public Health, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Laxmee Ramkhelawon
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Paul T Heath
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Kirsty Le Doare
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK.,Pathogen Immunity Group, Public Health England, Porton Down,UK.,Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine, Uganda Research Unit, Entebbe, Uganda
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31
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Ratner AJ. Enhanced Postnatal Acquisition of Hypervirulent Group B Streptococcus. Clin Infect Dis 2019; 69:1749-1751. [PMID: 30945730 PMCID: PMC6821193 DOI: 10.1093/cid/ciz035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 01/10/2019] [Indexed: 12/28/2022] Open
Affiliation(s)
- Adam J Ratner
- Departments of Pediatrics and Microbiology, New York University School of Medicine, New York
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Characterization and Protective Activity of Monoclonal Antibodies Directed against Streptococcus suis Serotype 2 Capsular Polysaccharide Obtained Using a Glycoconjugate. Pathogens 2019; 8:pathogens8030139. [PMID: 31500262 PMCID: PMC6789524 DOI: 10.3390/pathogens8030139] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 08/29/2019] [Accepted: 09/03/2019] [Indexed: 02/06/2023] Open
Abstract
Streptococcus suis serotype 2 is an encapsulated bacterium and an important swine pathogen. Opsonizing antibody responses targeting capsular polysaccharides (CPSs) are protective against extracellular pathogens. To elucidate the protective activity of monoclonal antibodies (mAbs) directed against S. suis serotype 2 CPS, mice were immunized with a serotype 2 CPS-glycoconjugate and three hybridomas were isolated; of which, two were murine IgMs and the other a murine IgG1. Whereas the IgMs (mAbs 9E7 and 13C8) showed different reactivity levels with S. suis serotypes 1, 1/2, 2 and 14, the IgG1 (mAb 16H11) was shown to be serotype 2-specific. All mAbs targeted the sialylated chain of the CPSs. Using an opsonophagocytosis assay, the IgMs were opsonizing towards the S. suis serotypes to which they cross-react, while the IgG1 failed to induce bacterial elimination. In a model of mouse passive immunization followed by a lethal challenge with S. suis serotype 2, the IgG1 and IgM cross-reacting only with serotype 14 (mAb 13C8) failed to protect, while the IgM cross-reacting with serotypes 1, 1/2, and 14 (mAb 9E7) was shown to be protective by limiting bacteremia. These new mAbs show promise as new S. suis diagnostic tools, as well as potential for therapeutic applications.
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Novel Multiplex Immunoassays for Quantification of IgG against Group B Streptococcus Capsular Polysaccharides in Human Sera. mSphere 2019; 4:4/4/e00273-19. [PMID: 31391276 PMCID: PMC6686225 DOI: 10.1128/msphere.00273-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Group B Streptococcus (GBS) infections constitute a major cause of invasive disease during the first three months of life and an unmet medical need that could be addressed by maternal vaccination. The GBS capsular polysaccharides (CPSs) have shown promise as vaccine targets in clinical studies. A highly specific serological assay to quantify maternal and neonatal anti-CPS antibody levels will be instrumental for GBS vaccine licensure. Here, we describe the development and comparison of two novel multiplex immunoassays (MIAs) based on the Luminex technology for the quantification of IgG antibodies recognizing the five most frequent GBS capsular variants (Ia, Ib, II, III, and V) out of the ten types identified. The first assay is based on the use of biotinylated CPSs coupled to streptavidin-derivatized magnetic microspheres (Biotin-CPS MIA), while the second is a sandwich assay with plain CPSs coupled to magnetic microspheres coated with polysaccharide-specific mouse monoclonal antibodies (Sandwich MIA). Both assays showed good specificity, linearity, and precision, although the Biotin-CPS MIA presented higher sensitivity and lower complexity than the Sandwich MIA. A panel of human sera representing a wide range of anti-CPS IgG concentrations was tested in parallel by the two assays, which resulted in comparable titers. Our data support the preservation of antigenic epitopes in the biotinylated polysaccharides and the suitability of the Biotin-CPS MIA for the precise determination of GBS anti-CPS IgG concentrations in human sera.IMPORTANCE Group B streptococcal infections can cause death in neonates up to 3 months of age. Intrapartum antibiotic prophylaxis in GBS-colonized mothers has limited early infections but has no impact after the first week of life. The development of a maternal vaccine to address this unmet medical need has been identified as a priority by the World Health Organization, and the GBS CPSs are considered the best antigen targets. However, to date there are no accepted standardized assays to measure immune responses to the investigational vaccines and for establishment of serocorrelates of protection. Here, we describe the performance of two microsphere-based pentaplex immunoassays for the determination of antibodies recognizing the five most frequent GBS serotypes. Our data confirm that an assay based on biotinylated polysaccharides coupled to streptavidin microspheres would be suitable for the intended purpose.
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Abstract
The surface of the Gram-positive opportunistic pathogen Streptococcus agalactiae, or group B Streptococcus (GBS), harbors several carbohydrate and protein antigens with the potential to be effective vaccines. Capsular polysaccharides of all clinically-relevant GBS serotypes coupled to immunogenic proteins of both GBS and non-GBS origin have undergone extensive testing in animals that led to advanced clinical trials in healthy adult women. In addition, GBS proteins either alone or in combination have been tested in animals; a fusion protein construct has recently advanced to human clinical studies. Given our current understanding of the antigenicity and immunogenicity of the wide array of GBS surface antigens, formulations now exist for the generation of viable vaccines against diseases caused by GBS.
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The role of immune correlates of protection on the pathway to licensure, policy decision and use of group B Streptococcus vaccines for maternal immunization: considerations from World Health Organization consultations. Vaccine 2019; 37:3190-3198. [PMID: 31031031 PMCID: PMC6528168 DOI: 10.1016/j.vaccine.2019.04.039] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/10/2019] [Accepted: 04/11/2019] [Indexed: 12/27/2022]
Abstract
There is a major public health need for GBS vaccines for maternal immunization. Important obstacles lie in the way of a pivotal clinical efficacy trial for licensure. A vaccine development pathway based on an immune correlate of protection is envisaged. Key considerations and priority activities for success are presented, based on WHO consultations.
The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined.
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Serocorrelates of protection against infant group B streptococcus disease. THE LANCET. INFECTIOUS DISEASES 2019; 19:e162-e171. [PMID: 30683467 DOI: 10.1016/s1473-3099(18)30659-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/20/2018] [Accepted: 10/24/2018] [Indexed: 12/12/2022]
Abstract
Group B streptococcus (GBS) is a leading cause of young infant mortality and morbidity globally, with vaccines being developed for over four decades but none licensed to date. A serocorrelate of protection against invasive disease in young infants is being considered to facilitate vaccine early licensure, followed by demonstration of efficacy assessed postlicensure. In this Review, we synthesise the available scientific evidence to define an immune correlate associated with GBS disease risk reduction on the basis of studies of natural infection. We summarise studies that have investigated GBS serum anticapsular or anti-protein antibodies, and studies measuring the association between antibody function and disease risk reduction. We highlight how knowledge on the development of correlates of protection from existing vaccines could be harnessed to facilitate GBS vaccine development. These lessons include aggregation of serocorrelates of protection for individual serotypes, understanding the relationship between immunity derived from natural exposure of adults and vaccine-induced immunity, or using extrapolation of protection from in-vitro immunoassay results. We also highlight key considerations for the assessment of the role of antibodies to derive a serocorrelate of risk reduction in future seroepidemiological studies of GBS disease.
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Bacterial Load and Molecular Markers Associated With Early-onset Group B Streptococcus: A Systematic Review and Meta-analysis. Pediatr Infect Dis J 2018; 37:e306-e314. [PMID: 29601454 DOI: 10.1097/inf.0000000000002050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND The natural history of neonatal group B Streptococcus (GBS) is poorly understood. Little is known about the bacterial factors influencing the transmission of GBS from mother to neonate, or the development of invasive early-onset GBS disease (EOGBS) in colonized neonates. We reviewed whether bacterial load and molecular markers are associated with GBS vertical transmission and progression to EOGBS. METHODS We searched Medline, Embase, Cochrane and Web of Science from inception to October 10, 2016, for observational studies in English. We also hand-searched reference lists of relevant publications and experts cross-checked included studies. Two reviewers independently screened studies, extracted data and appraised the quality of included studies using the Quality in Prognosis Studies tool. We conducted random-effects meta-analyses where possible and narratively synthesized the evidence in text and tables. RESULTS Seventeen studies were included from 1107 records retrieved from electronic databases and publication references. Meta-analyses of 3 studies showed that neonates colonized by serotype III had a higher risk of developing EOGBS than serotype Ia (pooled risk ratio: 1.51, 95% confidence interval: 1.12-2.03) and serotype II (risk ratio: 1.95, 95% confidence interval: 1.10-3.45). Eleven studies showed that in heavily colonized mothers, 2-3 times more neonates were colonized, and in heavily colonized neonates, up to 15 times more neonates had EOGBS, compared with light colonization. Most evidence was published before 2000 and was at risk of bias. CONCLUSIONS Acknowledging the difficulty of natural history studies, well-controlled studies are needed to assess the predictive value of pathogen subtype and heavy load; they may be useful for better-targeted prevention.
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Dzanibe S, Madhi SA. Systematic review of the clinical development of group B streptococcus serotype-specific capsular polysaccharide-based vaccines. Expert Rev Vaccines 2018; 17:635-651. [PMID: 29961350 DOI: 10.1080/14760584.2018.1496021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Vaccination against group B Streptococcus (GBS) during pregnancy could provide protection against disease in the mother, fetus, and newborn. Immunity through transplacental acquired antibodies in the newborns could persist through early infancy, reducing the risk of early-onset (<7 days age) and late-onset (7-89 days age) disease. We conducted a systematic review of clinical trials on GBS capsular polysaccharide (CPS) vaccine to assess its safety and immunogenicity in pregnant and nonpregnant adults. AREAS COVERED We searched literature databases PubMed (Medline), Scopus, and the Cochrane library and identified 25 unique records on GBS CPS vaccines with or without conjugant protein. EXPERT COMMENTARY GBS vaccines were well tolerated, with mild local reactogenicity being the main solicited adverse event and no difference in reporting of other serious adverse events compared to placebo recipients. CPS vaccines conjugated to immunogenic proteins induced ≥fourfold increase of serotype-specific antibodies with high longevity (1-2 years); and capable of promoting homotypic GBS opsonophagocytic killing. Feto-maternal transplacental antibody ratio of serotype-specific IgG ranged between 0.49 and 0.81. The clinical relevance of these immunogenicity studies, however, need to be weighed against a correlate of protection against invasive GBS disease in infants, which is yet to be established using a universally accepted standardized assay.
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Affiliation(s)
- Sonwabile Dzanibe
- a Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa.,b Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa.,c Division of Immunology , University of Cape Town , Cape Town , South Africa
| | - Shabir A Madhi
- a Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa.,b Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa
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Fabbrini M, Rigat F, Tuscano G, Chiarot E, Donders G, Devlieger R, Filippini S, Frigimelica E, Forte P, Wittke F, Halperin SA, Slobod K, Grandi G, Margarit I. Functional activity of maternal and cord antibodies elicited by an investigational group B Streptococcus trivalent glycoconjugate vaccine in pregnant women. J Infect 2018; 76:449-456. [DOI: 10.1016/j.jinf.2018.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/24/2017] [Accepted: 01/06/2018] [Indexed: 10/18/2022]
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Shabayek S, Spellerberg B. Group B Streptococcal Colonization, Molecular Characteristics, and Epidemiology. Front Microbiol 2018; 9:437. [PMID: 29593684 PMCID: PMC5861770 DOI: 10.3389/fmicb.2018.00437] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/26/2018] [Indexed: 11/13/2022] Open
Abstract
Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of serious neonatal infections. GBS is an opportunistic commensal constituting a part of the intestinal and vaginal physiologic flora and maternal colonization is the principal route of GBS transmission. GBS is a pathobiont that converts from the asymptomatic mucosal carriage state to a major bacterial pathogen causing severe invasive infections. At present, as many as 10 serotypes (Ia, Ib, and II–IX) are recognized. The aim of the current review is to shed new light on the latest epidemiological data and clonal distribution of GBS in addition to discussing the most important colonization determinants at a molecular level. The distribution and predominance of certain serotypes is susceptible to variations and can change over time. With the availability of multilocus sequence typing scheme (MLST) data, it became clear that GBS strains of certain clonal complexes possess a higher potential to cause invasive disease, while other harbor mainly colonizing strains. Colonization and persistence in different host niches is dependent on the adherence capacity of GBS to host cells and tissues. Bacterial biofilms represent well-known virulence factors with a vital role in persistence and chronic infections. In addition, GBS colonization, persistence, translocation, and invasion of host barriers are largely dependent on their adherence abilities to host cells and extracellular matrix proteins (ECM). Major adhesins mediating GBS interaction with host cells include the fibrinogen-binding proteins (Fbs), the laminin-binding protein (Lmb), the group B streptococcal C5a peptidase (ScpB), the streptococcal fibronectin binding protein A (SfbA), the GBS immunogenic bacterial adhesin (BibA), and the hypervirulent adhesin (HvgA). These adhesins facilitate persistent and intimate contacts between the bacterial cell and the host, while global virulence regulators play a major role in the transition to invasive infections. This review combines for first time epidemiological data with data on adherence and colonization for GBS. Investigating the epidemiology along with understanding the determinants of mucosal colonization and the development of invasive disease at a molecular level is therefore important for the development of strategies to prevent invasive GBS disease worldwide.
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Affiliation(s)
- Sarah Shabayek
- Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
| | - Barbara Spellerberg
- Institute of Medical Microbiology and Hygiene, University of Ulm, Ulm, Germany
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Protective effect of Group B Streptococcus type-III polysaccharide conjugates against maternal colonization, ascending infection and neonatal transmission in rodent models. Sci Rep 2018; 8:2593. [PMID: 29416049 PMCID: PMC5803199 DOI: 10.1038/s41598-018-20609-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/18/2018] [Indexed: 12/25/2022] Open
Abstract
Group B Streptococcus (GBS) is a normal inhabitant of recto-vaginal mucosae in up to 30% of healthy women. Colonization is a major risk factor for perinatal infection which can lead to severe complications such as stillbirth and neonatal invasive disease. Intra-partum antibiotic prophylaxis in colonized women is a safe and cost-effective preventive measure against early-onset disease in the first days of life, but has no effect on late-onset manifestations or on early maternal infection. Maternal immunization with capsular polysaccharide-based vaccines shows promise for the prevention of both early-onset and late-onset neonatal infections, although ability to prevent maternal colonization and ascending infection has been less studied. Here we investigated the effect of a GBS glycoconjugate vaccine since the very early stage of maternal GBS acquisition to neonatal outcome by rodent models of vaginal colonization and ascending infection. Immunization of female mice and rats with a type III glycoconjugate reduced vaginal colonization, infection of chorioamniotic/ placental membranes and bacterial transmission to fetuses and pups. Type III specific antibodies were detected in the blood and vagina of vaccinated mothers and their offspring. The obtained data support a potential preventive effect of GBS glycoconjugate vaccines during the different stages of pregnancy.
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Association between antibodies against group B Streptococcus surface proteins and recto-vaginal colonisation during pregnancy. Sci Rep 2017; 7:16454. [PMID: 29184151 PMCID: PMC5705700 DOI: 10.1038/s41598-017-16757-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 11/16/2017] [Indexed: 11/08/2022] Open
Abstract
Group B Streptococcus (GBS) recto-vaginal colonisation in pregnant women is the major risk factor for early-onset invasive GBS disease in their newborns. We aimed to determine the association between serum antibody levels against 11 GBS surface proteins and recto-vaginal acquisition of GBS colonisation during pregnancy. Sera collected from pregnant women at 20-25 weeks and ≥37 weeks of gestation age were measured for IgG titres against GBS surface proteins using a multiplex immunoassay. Women were evaluated for recto-vaginal colonisation every 4-5 weeks. We observed that the likelihood of becoming colonised with GBS during pregnancy was lower in women with IgG titres ≥200 U/mL against gbs0233 (adjusted OR = 0.47 [95% CI: 0.25-0.89], p = 0.021) and ≥85 U/mL for gbs1539 (adjusted OR = 0.44 [95% CI: 0.24-0.82], p = 0.01) when comparing between women who acquired GBS colonisation and those that remained free of GBS colonisation throughout pregnancy. IgG titres (U/mL) specific to BibA and Sip were higher in pregnant women colonised with GBS (380.19 and 223.87, respectively) compared to women with negative GBS cultures (234.42 and 186.21, respectively; p < 0.01) at ≥37 weeks gestation. Antibodies induced by gbs0233 and gbs1539 were associated with a reduced likelihood of recto-vaginal GBS acquisition during pregnancy and warrant further investigation as vaccine targets.
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Intrinsic Maturational Neonatal Immune Deficiencies and Susceptibility to Group B Streptococcus Infection. Clin Microbiol Rev 2017; 30:973-989. [PMID: 28814408 DOI: 10.1128/cmr.00019-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Although a normal member of the gastrointestinal and vaginal microbiota, group B Streptococcus (GBS) can also occasionally be the cause of highly invasive neonatal disease and is an emerging pathogen in both elderly and immunocompromised adults. Neonatal GBS infections are typically transmitted from mother to baby either in utero or during passage through the birth canal and can lead to pneumonia, sepsis, and meningitis within the first few months of life. Compared to the adult immune system, the neonatal immune system has a number of deficiencies, making neonates more susceptible to infection. Recognition of GBS by the host immune system triggers an inflammatory response to clear the pathogen. However, GBS has developed several mechanisms to evade the host immune response. A comprehensive understanding of this interplay between GBS and the host immune system will aid in the development of new preventative measures and therapeutics.
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Choi MJ, Noh JY, Cheong HJ, Kim WJ, Lin SM, Zhi Y, Lim JH, Lim S, Seo HS, Song JY. Development of a multiplexed opsonophagocytic killing assay (MOPA) for group B Streptococcus. Hum Vaccin Immunother 2017; 14:67-73. [PMID: 28933634 DOI: 10.1080/21645515.2017.1377379] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Group B Streptococcus (GBS) is a leading cause of sepsis in infants as well as chorioamnionitis in pregnant women. Opsonophagocytic killing assays (OPAs) are an essential technique in vaccine studies of encapsulated bacteria for estimating serotype-specific functional antibody levels in vitro. Here, we developed a three-fold multiplexed OPA (MOPA) to enable practical, large-scale assessment of GBS vaccine immunogenicity, including against serotypes Ia, III, and V. First, three target bacteria strains resistant to streptomycin, spectinomycin, or kanamycin were generated by natural selection through exposure to increasing antibiotic concentrations. Since a high level of nonspecific killing (NSK) of serotype V was observed in a 12.5% baby rabbit complement (BRC) solution, the BRC concentration was optimized. The final GBS-MOPA BRC concentration was 9%, which resulted in less than 20% NSK. The specificity was measured by preabsorbing serum with inactivated GBS. The opsonic index (OI) of preabsorbed serum with the homologous serotype GBS was significantly reduced in all three serotypes tested. The accuracy of the MOPA was compared with that of a single OPA (SOPA) with 35 serum samples. The OIs of the MOPA correlated well with those of the SOPA, and the r2 values were higher than 0.950 for all three serotypes. The precision of the MOPA assay was assessed in five independent experiments with five serum samples. The inter-assay precision of the GBS-MOPA was 12.5% of the average coefficient of variation. This is the first report to develop and standardize a GBS-MOPA, which will be useful for GBS vaccine development and evaluation.
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Affiliation(s)
- Min Joo Choi
- a Department of Internal Medicine , Korea University College of Medicine , Seoul , Republic of Korea
| | - Ji Yun Noh
- a Department of Internal Medicine , Korea University College of Medicine , Seoul , Republic of Korea
| | - Hee Jin Cheong
- a Department of Internal Medicine , Korea University College of Medicine , Seoul , Republic of Korea
| | - Woo Joo Kim
- a Department of Internal Medicine , Korea University College of Medicine , Seoul , Republic of Korea
| | - Shun-Mei Lin
- b Biotechnology Division, Korea Atomic Energy Research Institute , Jeongeup , Republic of Korea
| | - Yong Zhi
- b Biotechnology Division, Korea Atomic Energy Research Institute , Jeongeup , Republic of Korea
| | - Jae Hyang Lim
- c Department of Microbiology and Tissue Injury Defense Research Center , Ewha Womans University School of Medicine , Seoul , Republic of Korea
| | - Sangyong Lim
- b Biotechnology Division, Korea Atomic Energy Research Institute , Jeongeup , Republic of Korea
| | - Ho Seong Seo
- b Biotechnology Division, Korea Atomic Energy Research Institute , Jeongeup , Republic of Korea
| | - Joon Young Song
- a Department of Internal Medicine , Korea University College of Medicine , Seoul , Republic of Korea
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Lazzarin M, Mu R, Fabbrini M, Ghezzo C, Rinaudo CD, Doran KS, Margarit I. Contribution of pilus type 2b to invasive disease caused by a Streptococcus agalactiae ST-17 strain. BMC Microbiol 2017; 17:148. [PMID: 28673237 PMCID: PMC5496222 DOI: 10.1186/s12866-017-1057-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 06/23/2017] [Indexed: 12/02/2022] Open
Abstract
Background Group B Streptococcus (GBS) is a major cause of invasive disease especially in neonates. In GBS three structurally distinct pilus polymers have been identified as important virulence factors and promising vaccine candidates. The vast majority of Group B Streptococci belonging to the hypervirulent serotype III ST-17 lineage bear pilus types 1 and 2b. The purpose of this study was to investigate the relative contribution of these two pilus types to the pathogenesis of a ST-17 strain. Results We performed in vivo and in vitro analysis of isogenic knockout mutants derived from the GBS COH1 ST-17 strain deprived of either pilus type 1 or 2b. We compared the two pilus mutants with the wild type strain in a mouse model of invasive disease, in vitro survival in macrophages, and adherence/invasion assays using human brain endothelial and lung epithelial cell lines. Significantly less of the pilus 2b mutant was recovered from the blood, lungs and brain tissue of infected mice compared to the wild-type and pilus 1 mutant strains. Further, while the pilus 2b mutant survived similarly in murine macrophages, it exhibited a lower capacity to adhere and invade human brain epithelial and lung endothelial cell lines. Conclusions The data suggest an important role of pilus 2b in mediating GBS infection and host cell interaction of strains belonging to the hypervirulent GBS ST-17 lineage.
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Affiliation(s)
| | - Rong Mu
- Department of Biology and Center for Microbial Sciences, San Diego State University, 5500 Campanile Dr., NLS 317, San Diego, CA, 92182, USA
| | | | | | | | - Kelly S Doran
- Department of Biology and Center for Microbial Sciences, San Diego State University, 5500 Campanile Dr., NLS 317, San Diego, CA, 92182, USA.,Department of Pediatrics, University of California San Diego School of Medicine, La Jolla, CA, 92093, USA
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Vornhagen J, Adams Waldorf KM, Rajagopal L. Perinatal Group B Streptococcal Infections: Virulence Factors, Immunity, and Prevention Strategies. Trends Microbiol 2017. [PMID: 28633864 DOI: 10.1016/j.tim.2017.05.013] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Group B streptococcus (GBS) or Streptococcus agalactiae is a β-hemolytic, Gram-positive bacterium that is a leading cause of neonatal infections. GBS commonly colonizes the lower gastrointestinal and genital tracts and, during pregnancy, neonates are at risk of infection. Although intrapartum antibiotic prophylaxis during labor and delivery has decreased the incidence of early-onset neonatal infection, these measures do not prevent ascending infection that can occur earlier in pregnancy leading to preterm births, stillbirths, or late-onset neonatal infections. Prevention of GBS infection in pregnancy is complex and is likely influenced by multiple factors, including pathogenicity, host factors, vaginal microbiome, false-negative screening, and/or changes in antibiotic resistance. A deeper understanding of the mechanisms of GBS infections during pregnancy will facilitate the development of novel therapeutics and vaccines. Here, we summarize and discuss important advancements in our understanding of GBS vaginal colonization, ascending infection, and preterm birth.
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Affiliation(s)
- Jay Vornhagen
- Department of Global Health, University of Washington, Seattle, WA, USA; Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Kristina M Adams Waldorf
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA; Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
| | - Lakshmi Rajagopal
- Department of Global Health, University of Washington, Seattle, WA, USA; Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA; Department of Pediatrics, University of Washington, Seattle, WA, USA.
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Morrissey SM, Nielsen M, Ryan L, Al Dhanhani H, Meehan M, McDermott S, O'Sullivan N, Doyle M, Gavin P, O'Sullivan N, Cunney R, Drew RJ. Group B streptococcal PCR testing in comparison to culture for diagnosis of late onset bacteraemia and meningitis in infants aged 7-90 days: a multi-centre diagnostic accuracy study. Eur J Clin Microbiol Infect Dis 2017; 36:1317-1324. [PMID: 28247153 DOI: 10.1007/s10096-017-2938-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 02/08/2017] [Indexed: 12/15/2022]
Abstract
The aim of this study was to compare an in-house real-time PCR assay, with bacterial culture as the reference, for the diagnosis of late onset group B Streptococcal (GBS) disease. This was a retrospective review. All children aged 7-90 days presenting to four paediatric centres that had a blood or CSF sample tested by GBS PCR were included. Of 7,686 blood and 2,495 cerebrospinal fluid (CSF) samples from patients of all ages received for PCR testing, 893 and 859 samples were eligible for the study, respectively. When compared to culture, the sensitivity of blood PCR was 65% (13/20) in comparison to the CSF PCR test which was 100% (5/5). Ten of 23 PCR-positive blood samples and 17 of 22 PCR-positive CSF samples were culture negative. The median threshold Ct values for culture-positive/PCR-positive CSF samples was lower than that of culture-negative/PCR-positive CSF samples (p = 0.08). Clinical details of 17 available cases that were culture negative/PCR positive were reviewed; seven were deemed to be definite cases, eight were probable and two were possible. The results showed that detection of GBS by PCR is useful for CSF samples from infants aged 7-90 days with suspected meningitis; however, analysis of blood samples by PCR is of limited value as a routine screening test for late onset GBS sepsis and should not replace bacterial culture.
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Affiliation(s)
- S M Morrissey
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland
| | - M Nielsen
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland
| | - L Ryan
- Department of Microbiology, University Hospital Waterford, Co. Waterford, Ireland
| | - H Al Dhanhani
- Departments of Microbiology and Paediatric Infectious Diseases, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland
| | - M Meehan
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland
| | - S McDermott
- Department of Microbiology, Our Lady's Hospital, Co. Louth, Drogheda, Ireland
| | - N O'Sullivan
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland
| | - M Doyle
- Department of Microbiology, University Hospital Waterford, Co. Waterford, Ireland
| | - P Gavin
- Departments of Microbiology and Paediatric Infectious Diseases, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland
| | - N O'Sullivan
- Departments of Microbiology and Paediatric Infectious Diseases, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland
| | - R Cunney
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland
| | - R J Drew
- Irish Meningitis and Sepsis Reference Laboratory, Temple Street Children's University Hospital, Dublin 1, Ireland. .,Department of Microbiology, Rotunda Hospital, Dublin 1, Ireland. .,Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Dublin 2, Ireland. .,Rotunda Hospital, Parnell Square, Dublin 1, Ireland.
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Madhi SA, Dangor Z. Prospects for preventing infant invasive GBS disease through maternal vaccination. Vaccine 2017; 35:4457-4460. [PMID: 28237500 DOI: 10.1016/j.vaccine.2017.02.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/05/2017] [Accepted: 02/08/2017] [Indexed: 11/26/2022]
Abstract
Group B streptococcus (GBS) is a leading cause of neonatal sepsis, with the highest incidence (1.3 per 1000 live births) reported from Africa. Although the incidence of invasive GBS disease is reportedly low in South Asia, there is disconnect between prevalence of maternal recto-vaginal colonization and the incidence of early-onset disease (EOD). This is possibly due to case-ascertainment biases that omit investigation of newborns dying on day-0 of life, which accounts for >90% of EOD. Furthermore, GBS is associated with approximately 15% of all infection related stillbirths. Vaccination of pregnant women with a serotype-specific polysaccharide epitope vaccine could possibly protect against EOD and late-onset disease (LOD) in their infants through transplacental transfer of serotype-specific capsular antibody. Furthermore, vaccination of pregnant women might also protect against impaired neurodevelopment following GBS associated neonatal sepsis, and fetal loss/stillbirths. Licensure of a GBS vaccine might be feasible based on safety evaluation and a sero-correlate of protection, with vaccine effectiveness subsequently being demonstrated in phase IV studies. A randomized-controlled trial would, however, be best suited as a vaccine-probe to fully characterize the contribution of GBS to neonatal sepsis associated morbidity and mortality and adverse fetal outcomes.
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Affiliation(s)
- Shabir A Madhi
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa; Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, South Africa.
| | - Ziyaad Dangor
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa; Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand, South Africa; Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, South Africa.
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