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Li S, Liang H, Zhao SH, Yang XY, Guo Z. Recent progress in pneumococcal protein vaccines. Front Immunol 2023; 14:1278346. [PMID: 37818378 PMCID: PMC10560988 DOI: 10.3389/fimmu.2023.1278346] [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: 08/16/2023] [Accepted: 09/07/2023] [Indexed: 10/12/2023] Open
Abstract
Pneumococcal infections continue to pose a significant global health concern, necessitating the development of effective vaccines. Despite the progress shown by pneumococcal polysaccharide and conjugate vaccines, their limited coverage and the emergence of non-vaccine serotypes have highlighted the need for alternative approaches. Protein-based pneumococcal vaccines, targeting conserved surface proteins of Streptococcus pneumoniae, have emerged as a promising strategy. In this review, we provide an overview of the advancements made in the development of pneumococcal protein vaccines. We discuss the key protein vaccine candidates, highlight their vaccination results in animal studies, and explore the challenges and future directions in protein-based pneumococcal vaccine.
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Affiliation(s)
- Sha Li
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, School of Bioengineering, Zunyi Medical University, Zhuhai, Guangdong, China
| | - Hangeri Liang
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, School of Bioengineering, Zunyi Medical University, Zhuhai, Guangdong, China
| | - Shui-Hao Zhao
- Center for Biological Science and Technology, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, Guangdong, China
| | - Xiao-Yan Yang
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, School of Bioengineering, Zunyi Medical University, Zhuhai, Guangdong, China
| | - Zhong Guo
- Center for Biological Science and Technology, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, Guangdong, China
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Umemoto S, Nakahashi-Ouchida R, Yuki Y, Kurokawa S, Machita T, Uchida Y, Mori H, Yamanoue T, Shibata T, Sawada SI, Ishige K, Hirano T, Fujihashi K, Akiyoshi K, Kurashima Y, Tokuhara D, Ernst PB, Suzuki M, Kiyono H. Cationic-nanogel nasal vaccine containing the ectodomain of RSV-small hydrophobic protein induces protective immunity in rodents. NPJ Vaccines 2023; 8:106. [PMID: 37488116 PMCID: PMC10366164 DOI: 10.1038/s41541-023-00700-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 06/22/2023] [Indexed: 07/26/2023] Open
Abstract
Respiratory syncytial virus (RSV) is a leading cause of upper and lower respiratory tract infection, especially in children and the elderly. Various vaccines containing the major transmembrane surface proteins of RSV (proteins F and G) have been tested; however, they have either afforded inadequate protection or are associated with the risk of vaccine-enhanced disease (VED). Recently, F protein-based maternal immunization and vaccines for elderly patients have shown promising results in phase III clinical trials, however, these vaccines have been administered by injection. Here, we examined the potential of using the ectodomain of small hydrophobic protein (SHe), also an RSV transmembrane surface protein, as a nasal vaccine antigen. A vaccine was formulated using our previously developed cationic cholesteryl-group-bearing pullulan nanogel as the delivery system, and SHe was linked in triplicate to pneumococcal surface protein A as a carrier protein. Nasal immunization of mice and cotton rats induced both SHe-specific serum IgG and mucosal IgA antibodies, preventing viral invasion in both the upper and lower respiratory tracts without inducing VED. Moreover, nasal immunization induced greater protective immunity against RSV in the upper respiratory tract than did systemic immunization, suggesting a critical role for mucosal RSV-specific IgA responses in viral elimination at the airway epithelium. Thus, our nasal vaccine induced effective protection against RSV infection in the airway mucosa and is therefore a promising vaccine candidate for further development.
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Affiliation(s)
- Shingo Umemoto
- Division of Mucosal Immunology, IMSUT Distinguished Professor Unit, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Otorhinolaryngology & Head and Neck Surgery, Faculty of Medicine, Oita University, Oita, Japan
- Chiba University-University of California San Diego Center for Mucosal Immunology, Allergy and Vaccine (CU-UCSD cMAV), Department of Medicine, School of Medicine, San Diego, CA, USA
| | - Rika Nakahashi-Ouchida
- Division of Mucosal Immunology, IMSUT Distinguished Professor Unit, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
- Chiba University Synergy Institute for Futuristic Mucosal Vaccine Research and Development, Chiba University, Chiba, Japan
| | - Yoshikazu Yuki
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
- HanaVax Inc, Tokyo, Japan
| | - Shiho Kurokawa
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
| | - Tomonori Machita
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
| | - Yohei Uchida
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
| | - Hiromi Mori
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
| | - Tomoyuki Yamanoue
- Division of Mucosal Vaccines, International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
| | - Takehiko Shibata
- Department of Microbiology, Tokyo Medical University, Tokyo, Japan
- Department of Immunology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Shin-Ichi Sawada
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Kazuya Ishige
- Biochemicals Division, Yamasa Corporation, Chiba, Japan
| | - Takashi Hirano
- Department of Otorhinolaryngology & Head and Neck Surgery, Faculty of Medicine, Oita University, Oita, Japan
| | - Kohtaro Fujihashi
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
- Chiba University Synergy Institute for Futuristic Mucosal Vaccine Research and Development, Chiba University, Chiba, Japan
- Division of Mucosal Vaccines, International Vaccine Design Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Department of Pediatric Dentistry, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kazunari Akiyoshi
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Yosuke Kurashima
- Division of Mucosal Immunology, IMSUT Distinguished Professor Unit, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Chiba University-University of California San Diego Center for Mucosal Immunology, Allergy and Vaccine (CU-UCSD cMAV), Department of Medicine, School of Medicine, San Diego, CA, USA
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan
- Chiba University Synergy Institute for Futuristic Mucosal Vaccine Research and Development, Chiba University, Chiba, Japan
- Division of Mucosal Vaccines, International Vaccine Design Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Institute for Advanced Academic Research, Chiba University, Chiba, Japan
- Department of Innovative Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Daisuke Tokuhara
- Chiba University-University of California San Diego Center for Mucosal Immunology, Allergy and Vaccine (CU-UCSD cMAV), Department of Medicine, School of Medicine, San Diego, CA, USA
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | - Peter B Ernst
- Chiba University-University of California San Diego Center for Mucosal Immunology, Allergy and Vaccine (CU-UCSD cMAV), Department of Medicine, School of Medicine, San Diego, CA, USA
- Division of Comparative Pathology and Medicine, Department of Pathology, University of California, San Diego, CA, USA
- Center for Veterinary Sciences and Comparative Medicine, University of California, San Diego, CA, USA
- Future Medicine Education and Research Organization, Chiba University, Chiba, Japan
| | - Masashi Suzuki
- Department of Otorhinolaryngology & Head and Neck Surgery, Faculty of Medicine, Oita University, Oita, Japan
| | - Hiroshi Kiyono
- Division of Mucosal Immunology, IMSUT Distinguished Professor Unit, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
- Chiba University-University of California San Diego Center for Mucosal Immunology, Allergy and Vaccine (CU-UCSD cMAV), Department of Medicine, School of Medicine, San Diego, CA, USA.
- Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan.
- Chiba University Synergy Institute for Futuristic Mucosal Vaccine Research and Development, Chiba University, Chiba, Japan.
- HanaVax Inc, Tokyo, Japan.
- Future Medicine Education and Research Organization, Chiba University, Chiba, Japan.
- Mucosal Immunology and Allergy Therapeutics, Institute for Global Prominent Research, Chiba University, Chiba, Japan.
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Park WJ, Yoon YK, Kim Y, Park JS, Pansuriya R, Cho SN, Seok YJ, Ganapathy R. Development of a bivalent conjugate vaccine candidate against rotaviral diarrhea and tuberculosis using polysaccharide from Mycobacterium tuberculosis conjugated to ΔVP8* protein from rotavirus. Vaccine 2021; 39:6644-6652. [PMID: 34642087 DOI: 10.1016/j.vaccine.2021.09.067] [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: 04/06/2021] [Revised: 08/20/2021] [Accepted: 09/28/2021] [Indexed: 11/25/2022]
Abstract
Conjugation of carbohydrate antigens with a carrier protein is a clinically proven strategy to overcome the poor immunogenicity of bacterial polysaccharide. In addition to its primary role, which is to help generate a T cell-mediate long-lasting immune response directed against the carbohydrate antigen, the carrier protein in a glycoconjugate vaccine can also play an important role as a protective antigen. Among carrier proteins currently used in licensed conjugate vaccines, non-typeable Haemophilus influenzae protein D has been used as an antigenically active carrier protein. Our previous studies also indicate that some carrier proteins provide B cell epitopes, along with T cell helper epitopes. Herein we investigated the dual role of truncated rotavirus spike protein ΔVP8* as a carrier and a protective antigen. Capsular polysaccharide lipoarabinomannan (LAM), purified from Mycobacterium tuberculosis (M.tb), was chemically conjugated with ΔVP8*. Mouse immunization experiments showed that the resultant conjugates elicited strong and specific immune responses against the polysaccharide antigen, and the responses were comparable to those induced by Diphtheria toxoid (DT)-based conjugates. The conjugate vaccine induced enhanced antibody titers and functional antibodies against ΔVP8* when compared to immunization with the unconjugated ΔVP8*. Thus, these results indicate that ΔVP8* can be a relevant carrier protein for glycoconjugate vaccine and the glycoconjugates consisting of ΔVP8* with LAM are effective bivalent vaccine candidates against rotavirus and tuberculosis.
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Affiliation(s)
- Wook-Jin Park
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 08826, Republic of Korea; International Vaccine Institute, Seoul 08826, Republic of Korea
| | - Yeon-Kyung Yoon
- International Vaccine Institute, Seoul 08826, Republic of Korea
| | - Youngmi Kim
- College of Medicine and Institute for Immunology and Immunological Diseases, Yonsei University, Seoul 03722, Republic of Korea
| | - Ji-Sun Park
- International Vaccine Institute, Seoul 08826, Republic of Korea
| | | | - Sang-Nae Cho
- College of Medicine and Institute for Immunology and Immunological Diseases, Yonsei University, Seoul 03722, Republic of Korea
| | - Yeong-Jae Seok
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 08826, Republic of Korea
| | - Ravi Ganapathy
- International Vaccine Institute, Seoul 08826, Republic of Korea.
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Bazhenova A, Gao F, Bolgiano B, Harding SE. Glycoconjugate vaccines against Salmonella enterica serovars and Shigella species: existing and emerging methods for their analysis. Biophys Rev 2021; 13:221-246. [PMID: 33868505 PMCID: PMC8035613 DOI: 10.1007/s12551-021-00791-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/25/2021] [Indexed: 12/26/2022] Open
Abstract
The global spread of enteric disease, the increasingly limited options for antimicrobial treatment and the need for effective eradication programs have resulted in an increased demand for glycoconjugate enteric vaccines, made with carbohydrate-based membrane components of the pathogen, and their precise characterisation. A set of physico-chemical and immunological tests are employed for complete vaccine characterisation and to ensure their consistency, potency, safety and stability, following the relevant World Health Organization and Pharmacopoeia guidelines. Variable requirements for analytical methods are linked to conjugate structure, carrier protein nature and size and O-acetyl content of polysaccharide. We investigated a key stability-indicating method which measures the percent free saccharide of Salmonella enterica subspecies enterica serovar Typhi capsular polysaccharide, by detergent precipitation, depolymerisation and HPAEC-PAD quantitation. Together with modern computational approaches, a more precise design of glycoconjugates is possible, allowing for improvements in solubility, structural conformation and stability, and immunogenicity of antigens, which may be applicable to a broad spectrum of vaccines. More validation experiments are required to establish the most effective and suitable methods for glycoconjugate analysis to bring uniformity to the existing protocols, although the need for product-specific approaches will apply, especially for the more complex vaccines. An overview of current and emerging analytical approaches for the characterisation of vaccines against Salmonella Typhi and Shigella species is described in this paper. This study should aid the development and licensing of new glycoconjugate vaccines aimed at the prevention of enteric diseases.
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Affiliation(s)
- Aleksandra Bazhenova
- School of Biosciences, University of Nottingham, Sutton Bonington, Loughborough, LE12 5RD UK
| | - Fang Gao
- Division of Bacteriology, National Institute for Biological Standards and Control (NIBSC), Blanche Lane, South Mimms, Potters Bar, EN6 3QG UK
| | - Barbara Bolgiano
- Division of Bacteriology, National Institute for Biological Standards and Control (NIBSC), Blanche Lane, South Mimms, Potters Bar, EN6 3QG UK
| | - Stephen E. Harding
- School of Biosciences, University of Nottingham, Sutton Bonington, Loughborough, LE12 5RD UK
- Museum of Cultural History, University of Oslo, Postboks 6762 St. Olavs plass, 0130 Oslo, Norway
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Wang L, Tan Y, Wei C, Zhang H, Luo P, Zhang S, Ma X. A preliminary study on the application of PspA as a carrier for group A meningococcal polysaccharide. PLoS One 2019; 14:e0218427. [PMID: 31291272 PMCID: PMC6619668 DOI: 10.1371/journal.pone.0218427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 06/03/2019] [Indexed: 01/13/2023] Open
Abstract
This study aimed to explore the feasibility of pneumococcal surface protein A (PspA) as a carrier protein. Three recombinant pneumococcal surface proteins from three different clades were expressed by the prokaryotic expression system and conjugated to group A meningococcal polysaccharide (GAMP) to generate three polysaccharide-protein conjugates. The conjugates, unconjugated proteins, GAMP, and GAMP-TT vaccine bulk (used as positive control) were immunized into mice, and their immune effects were assessed by the methods of enzyme-linked immunosorbent assay (ELISA), flow cytometry (FCM), and serum bactericidal assay (SBA). The results showed that the polysaccharide-protein conjugates could produce higher levels of anti-GAMP IgG titers (P < 0.05), higher ratios of Th1/Th2 (P < 0.05), and higher levels of serum bactericidal activity (P < 0.05), compared with the unconjugated GAMP. The conjugation of PspAs to GAMP also enhanced the anti-PspA responses compared with unconjugated PspAs except for PspA3. In conclusion, the results indicated that the three PspAs were appropriate carrier proteins, as demonstrated by the characteristics of T-cell dependent responses to the GAMP, and might protect against group A of epidemic cerebrospinal meningitis.
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Affiliation(s)
- Lichan Wang
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Yajun Tan
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Chen Wei
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Huajie Zhang
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Peng Luo
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
| | - Shumin Zhang
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
- * E-mail: (SZ); (XM)
| | - Xiao Ma
- DTaP and toxins division, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China
- * E-mail: (SZ); (XM)
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Kye YC, Park SM, Shim BS, Firdous J, Kim G, Kim HW, Ju YJ, Kim CG, Cho CS, Kim DW, Cho JH, Song MK, Han SH, Yun CH. Intranasal immunization with pneumococcal surface protein A in the presence of nanoparticle forming polysorbitol transporter adjuvant induces protective immunity against the Streptococcus pneumoniae infection. Acta Biomater 2019; 90:362-372. [PMID: 30922953 DOI: 10.1016/j.actbio.2019.03.049] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 03/06/2019] [Accepted: 03/24/2019] [Indexed: 02/03/2023]
Abstract
Developing effective mucosal subunit vaccine for the Streptococcus pneumoniae has been unsuccessful mainly because of their poor immunogenicity with insufficient memory T and B cell responses. We thus address whether such limitation can be overcome by introducing effective adjuvants that can enhance immunity and show here that polysorbitol transporter (PST) serves as a mucosal adjuvant for a subunit vaccine against the Streptococcus pneumoniae. Pneumococcal surface protein A (PspA) with PST adjuvant induced protective immunity against S. pneumoniae challenge, especially long-term T and B cell immune responses. Moreover, we found that the PST preferentially induced T helper (Th) responses toward Th2 or T follicular helper (Tfh) cells and, importantly, that the responses were mediated through antigen-presenting cells via activating a peroxisome proliferator-activated receptor gamma (PPAR-γ) pathway. Thus, these data indicate that PST can be used as an effective and safe mucosal vaccine adjuvant against S. pneumoniae infection. STATE OF SIGNIFICANCE: In this study, we suggested the nanoparticle forming adjuvant, PST works as an effective adjuvant for the pneumococcal vaccine, PspA. The PspA subunit vaccine together with PST adjuvant efficiently induced protective immunity, even in the long-term memory responses, against Streptococcus pneumoniae lethal challenge. We found that PspA with PST adjuvant induced dendritic cell activation followed by follicular helper T cell responses through PPAR-γ pathway resulting long-term memory antibody-producing cells. Consequently, in this paper, we suggest the mechanism for safe nanoparticle forming subunit vaccine adjuvant against pneumococcal infection.
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Francis JP, Richmond PC, Strickland D, Prescott SL, Pomat WS, Michael A, Nadal-Sims MA, Edwards-Devitt CJ, Holt PG, Lehmann D, van den Biggelaar AHJ. Cord blood Streptococcus pneumoniae-specific cellular immune responses predict early pneumococcal carriage in high-risk infants in Papua New Guinea. Clin Exp Immunol 2016; 187:408-417. [PMID: 27859014 PMCID: PMC5290304 DOI: 10.1111/cei.12902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 10/03/2016] [Accepted: 10/27/2016] [Indexed: 12/01/2022] Open
Abstract
In areas where Streptococcus pneumoniae is highly endemic, infants experience very early pneumococcal colonization of the upper respiratory tract, with carriage often persisting into adulthood. We aimed to explore whether newborns in high‐risk areas have pre‐existing pneumococcal‐specific cellular immune responses that may affect early pneumococcal acquisition. Cord blood mononuclear cells (CBMC) of 84 Papua New Guinean (PNG; high endemic) and 33 Australian (AUS; low endemic) newborns were stimulated in vitro with detoxified pneumolysin (dPly) or pneumococcal surface protein A (PspA; families 1 and 2) and compared for cytokine responses. Within the PNG cohort, associations between CBMC dPly and PspA‐induced responses and pneumococcal colonization within the first month of life were studied. Significantly higher PspA‐specific interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α, interleukin (IL)‐5, IL‐6, IL‐10 and IL‐13 responses, and lower dPly‐IL‐6 responses were produced in CBMC cultures of PNG compared to AUS newborns. Higher CBMC PspA‐IL‐5 and PspA‐IL‐13 responses correlated with a higher proportion of cord CD4 T cells, and higher dPly‐IL‐6 responses with a higher frequency of cord antigen‐presenting cells. In the PNG cohort, higher PspA‐specific IL‐5 and IL‐6 CBMC responses were associated independently and significantly with increased risk of earlier pneumococcal colonization, while a significant protective effect was found for higher PspA‐IL‐10 CBMC responses. Pneumococcus‐specific cellular immune responses differ between children born in pneumococcal high versus low endemic settings, which may contribute to the higher risk of infants in high endemic settings for early pneumococcal colonization, and hence disease.
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Affiliation(s)
- J P Francis
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - P C Richmond
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - D Strickland
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - S L Prescott
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - W S Pomat
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - A Michael
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - M A Nadal-Sims
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - C J Edwards-Devitt
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - P G Holt
- Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - D Lehmann
- Telethon Kids Institute, University of Western Australia, Perth, Australia
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