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Campos CL, Gomes LR, Covarrubias AE, Kato EE, Souza GG, Vasconcellos SA, Heinemann MB, Martins EAL, Ho PL, Da Costa RMA, Da Silva JB. A Three-Dimensional Lung Cell Model to Leptospira Virulence Investigations. Curr Microbiol 2022; 79:57. [PMID: 34982247 DOI: 10.1007/s00284-021-02720-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 11/08/2021] [Indexed: 11/30/2022]
Abstract
Leptospirosis is a worldwide zoonosis and a serious public health threat in tropical and subtropical areas. The etiologic agents of leptospirosis are pathogenic spirochetes from the genus Leptospira. In severe cases, patients develop a pulmonary hemorrhage that is associated with high fatality rates. Several animal models were established for leptospirosis studies, such as rodents, dogs, and monkeys. Although useful to study the relationship among Leptospira and its hosts, the animal models still exhibit economic and ethical limitation reasons and do not fully represent the human infection. As an attempt to bridge the gap between animal studies and clinical information from patients, we established a three-dimensional (3-D) human lung cell culture for Leptospira infection. We show that Leptospira is able to efficiently infect the cell lung spheroids and also to infiltrate in deeper areas of the cell aggregates. The ability to infect the 3-D lung cell aggregates was time-dependent. The 3-D spheroids infection occurred up to 120 h in studies with two serovars, Canicola and Copenhageni. We standardized the number of bacteria in the initial inoculum for infection of the spheroids and we also propose two alternative culture media conditions. This new approach was validated by assessing the expression of three genes of Leptospira related to virulence and motility. The transcripts of these genes increased in both culture conditions, however, in higher rates and earlier times in the 3-D culture. We also assessed the production of chemokines by the 3-D spheroids before and after Leptospira infection, confirming induction of two of them, mainly in the 3-D spheroids. Chemokine CCL2 was expressed only in the 3-D cell culture. Increasing of this chemokine was observed previously in infected animal models. This new approach provides an opportunity to study the interaction of Leptospira with the human lung epithelium in vitro.
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Affiliation(s)
- Camila L Campos
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Luciana R Gomes
- Laboratório de Ciclo Celular-Center for Research on Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Ambart E Covarrubias
- Facultad de Ciencias de la Salud, Escuela de Tecnología Médica, Universidad San Sebastian, Concepción, Chile
| | - Ellen E Kato
- Laboratorio de Fisiopatologia, Instituto Butantan, São Paulo, Brazil
| | - Gisele G Souza
- Laboratório de Zoonoses Bacterianas, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Silvio A Vasconcellos
- Laboratório de Zoonoses Bacterianas, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Marcos B Heinemann
- Laboratório de Zoonoses Bacterianas, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | | | - Paulo L Ho
- Divisão BioIndustrial, Instituto Butantan, São Paulo, Brazil
| | - Renata M A Da Costa
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil.,Global Antibiotics Research and Development Partnership (GARDP), Chemin Louis-Dunant 15, 1202, Geneva, Switzerland
| | - Josefa B Da Silva
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil.
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2
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Chan WYK, Chim SHY, Tse DML, Ho PL. Acute flaccid paralysis associated with enterovirus D68 infection: a case report. Hong Kong Med J 2021; 27:355-357. [PMID: 34706986 DOI: 10.12809/hkmj208931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- W Y K Chan
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Hong Kong.,Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong
| | - S H Y Chim
- Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong
| | - D M L Tse
- Department of Diagnostic Radiology, Queen Mary Hospital, and St Teresa's Hospital, Hong Kong
| | - P L Ho
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
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3
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Aguiar RS, Pohl F, Morais GL, Nogueira FCS, Carvalho JB, Guida L, Arge LWP, Melo A, Moreira MEL, Cunha DP, Gomes L, Portari EA, Velasquez E, Melani RD, Pezzuto P, de Castro FL, Geddes VEV, Gerber AL, Azevedo GS, Schamber-Reis BL, Gonçalves AL, Junqueira-de-Azevedo I, Nishiyama MY, Ho PL, Schanoski AS, Schuch V, Tanuri A, Chimelli L, Vasconcelos ZFM, Domont GB, Vasconcelos ATR, Nakaya HI. Molecular alterations in the extracellular matrix in the brains of newborns with congenital Zika syndrome. Sci Signal 2020; 13:eaay6736. [PMID: 32518143 DOI: 10.1126/scisignal.aay6736] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Zika virus (ZIKV) infection during pregnancy can cause a set of severe abnormalities in the fetus known as congenital Zika syndrome (CZS). Experiments with animal models and in vitro systems have substantially contributed to our understanding of the pathophysiology of ZIKV infection. Here, to investigate the molecular basis of CZS in humans, we used a systems biology approach to integrate transcriptomic, proteomic, and genomic data from the postmortem brains of neonates with CZS. We observed that collagens were greatly reduced in expression in CZS brains at both the RNA and protein levels and that neonates with CZS had several single-nucleotide polymorphisms in collagen-encoding genes that are associated with osteogenesis imperfecta and arthrogryposis. These findings were validated by immunohistochemistry and comparative analysis of collagen abundance in ZIKV-infected and uninfected samples. In addition, we showed a ZIKV-dependent increase in the expression of cell adhesion factors that are essential for neurite outgrowth and axon guidance, findings that are consistent with the neuronal migration defects observed in CZS. Together, these findings provide insights into the underlying molecular alterations in the ZIKV-infected brain and reveal host genes associated with CZS susceptibility.
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Affiliation(s)
- Renato S Aguiar
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Fabio Pohl
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Guilherme L Morais
- National Laboratory of Scientific Computation, LNCC/MCTI, Petrópolis, Brazil
| | - Fabio C S Nogueira
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratory of Proteomics, LADETEC, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Joseane B Carvalho
- National Laboratory of Scientific Computation, LNCC/MCTI, Petrópolis, Brazil
| | - Letícia Guida
- Fernandes Figueira Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Luis W P Arge
- National Laboratory of Scientific Computation, LNCC/MCTI, Petrópolis, Brazil
| | - Adriana Melo
- Instituto de Pesquisa Professor Amorim Neto, Campina Grande, Paraíba, Brazil
| | | | - Daniela P Cunha
- Fernandes Figueira Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Leonardo Gomes
- Fernandes Figueira Institute, Fiocruz, Rio de Janeiro, Brazil
| | | | - Erika Velasquez
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rafael D Melani
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paula Pezzuto
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernanda L de Castro
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Victor E V Geddes
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alexandra L Gerber
- National Laboratory of Scientific Computation, LNCC/MCTI, Petrópolis, Brazil
| | - Girlene S Azevedo
- Instituto de Pesquisa Professor Amorim Neto, Campina Grande, Paraíba, Brazil
| | - Bruno L Schamber-Reis
- Faculdade de Ciências Médicas de Campina Grande, Núcleo de Genética Médica, Centro Universitário UniFacisa, Campina Grande, Paraíba, Brazil
| | - Alessandro L Gonçalves
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Milton Y Nishiyama
- Special Laboratory for Applied Toxinology, Butantan Institute, São Paulo, Brazil
| | - Paulo L Ho
- Bacteriology Laboratory, Butantan Institute, São Paulo, Brazil
| | | | - Viviane Schuch
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Amilcar Tanuri
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leila Chimelli
- Laboratório de Neuropatologia, Instituto Estadual do Cérebro, Rio de Janeiro, Brazil.
| | | | - Gilberto B Domont
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Ana T R Vasconcelos
- National Laboratory of Scientific Computation, LNCC/MCTI, Petrópolis, Brazil.
| | - Helder I Nakaya
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.
- Scientific Platform Pasteur-USP, São Paulo, Brazil
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4
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Lauretti-Ferreira F, Silva PLD, Alcântara NM, Silva BF, Grabher I, Souza GO, Nakajima E, Akamatsu MA, Vasconcellos SA, Abreu PAE, Carvalho E, Martins EAL, Ho PL, da Silva JB. New strategies for Leptospira vaccine development based on LPS removal. PLoS One 2020; 15:e0230460. [PMID: 32218590 PMCID: PMC7100938 DOI: 10.1371/journal.pone.0230460] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/01/2020] [Indexed: 12/29/2022] Open
Abstract
Pathogenic spirochetes from genus Leptospira are etiologic agents of leptospirosis. Cellular vaccines against Leptospira infection often elicit mainly response against the LPS antigen of the serovars present in the formulation. There is no suitable protein candidate capable of replacing whole-cell vaccines, thus requiring new approaches on vaccine development to improve leptospirosis prevention. Our goal was to develop a whole-cell vaccine sorovar-independent based on LPS removal and conservation of protein antigens exposure, to evaluate the protective capacity of monovalent or bivalent vaccines against homologous and heterologous virulent Leptospira in hamster. Leptospire were subjected to heat inactivation, or to LPS extraction with butanol and in some cases further inactivation with formaldehyde. Hamsters were immunized and challenged with homologous or heterologous virulent serovars, blood and organs were collected from the survivors for bacterial quantification, chemokine evaluation, and analysis of sera antibody reactivity and cross-reactivity by Western blot. Immunization with either heated or low LPS vaccines with serovar Copenhageni or Canicola resulted in 100% protection of the animals challenged with homologous virulent bacteria. Notably, different from the whole-cell vaccine, the low LPS vaccines produced with serovar Canicola provided only partial protection in heterologous challenge with the virulent Copenhageni serovar. Immunization with bivalent formulation results in 100% protection of immunized animals challenged with virulent serovar Canicola. All vaccines produced were able to eliminate bacteria from the kidney of challenged animals. All the vaccines raised antibodies capable to recognize antigens of serovars not present in the vaccine formulation. Transcripts of IFNγ, CXCL16, CCL5, CXCL10, CXCR6, and CCR5, increased in all immunized animals. Conclusion: Our results showed that bivalent vaccines with reduced LPS may be an interesting strategy for protection against heterologous virulent serovars. Besides the desirable multivalent protection, the low LPS vaccines are specially promising due to the expected lower reatogenicity.
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Affiliation(s)
- Fabiana Lauretti-Ferreira
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | | | | | - Bruna F. Silva
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Isabele Grabher
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Gisele O. Souza
- Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Erika Nakajima
- Laboratory of Process Development, Butantan Institute, São Paulo, Brazil
| | | | - Silvio A. Vasconcellos
- Laboratory of Bacterial Zoonosis, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | | | - Eneas Carvalho
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | | | - Paulo L. Ho
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
| | - Josefa B. da Silva
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
- * E-mail:
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5
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Castro JT, Oliveira GS, Nishigasako MA, Debrie AS, Miyaji EN, Soares-Schanoski A, Akamatsu MA, Locht C, Ho PL, Mielcarek N, Oliveira MLS. Correction: Evaluation of inactivated Bordetella pertussis as a delivery system for the immunization of mice with Pneumococcal Surface Antigen A. PLoS One 2020; 15:e0229050. [PMID: 32023329 PMCID: PMC7001929 DOI: 10.1371/journal.pone.0229050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pone.0228055.].
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6
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Castro JT, Oliveira GS, Nishigasako MA, Debrie AS, Miyaji EN, Soares-Schanoski A, Akamatsu MA, Locht C, Ho PL, Mielcarek N, Oliveira MLS. Evaluation of inactivated Bordetella pertussis as a delivery system for the immunization of mice with Pneumococcal Surface Antigen A. PLoS One 2020; 15:e0228055. [PMID: 31945121 PMCID: PMC6964896 DOI: 10.1371/journal.pone.0228055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 01/06/2020] [Indexed: 11/19/2022] Open
Abstract
Pneumococcal Surface Protein A (PspA) has been successfully tested as vaccine candidate against Streptococcus pneumoniae infections. Vaccines able to induce PspA-specific antibodies and Th1 cytokines usually provide protection in mice. We have shown that the whole cell pertussis vaccine (wP) or components from acellular pertussis vaccines, such as Pertussis Toxin or Filamentous Hemagglutinin (FHA), are good adjuvants to PspA, suggesting that combined pertussis-PspA vaccines would be interesting strategies against the two infections. Here, we evaluated the potential of wP as a delivery vector to PspA. Bordetella pertussis strains producing a PspA from clade 4 (PspA4Pro) fused to the N-terminal region of FHA (Fha44) were constructed and inactivated with formaldehyde for the production of wPPspA4Pro. Subcutaneous immunization of mice with wPPspA4Pro induced low levels of anti-PspA4 IgG, even after 3 doses, and did not protect against a lethal pneumococcal challenge. Prime-boost strategies using wPPspA4Pro and PspA4Pro showed that there was no advantage in using the wPPspA4Pro vaccine. Immunization of mice with purified PspA4Pro induced higher levels of antibodies and protection against pneumococcal infection than the prime-boost strategies. Finally, purified Fha44:PspA4Pro induced high levels of anti-PspA4Pro IgG, but no protection, suggesting that the antibodies induced by the fusion protein were not directed to protective epitopes.
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Affiliation(s)
- Julia T. Castro
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP, Brazil
| | | | | | - Anne-Sophie Debrie
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 –UMR 8204 –CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Eliane N. Miyaji
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, SP, Brazil
| | | | - Milena A. Akamatsu
- Seção de Vacinas Aeróbicas, Divisão Bioindustrial, Instituto Butantan, São Paulo, SP, Brazil
| | - Camille Locht
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 –UMR 8204 –CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Paulo L. Ho
- Seção de Vacinas Aeróbicas, Divisão Bioindustrial, Instituto Butantan, São Paulo, SP, Brazil
| | - Nathalie Mielcarek
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 –UMR 8204 –CIIL—Center for Infection and Immunity of Lille, Lille, France
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7
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Chan AMW, Au WWY, Chao DVK, Choi K, Choi KW, Choi SMY, Chow Y, Fan CYM, Ho PL, Hui EMT, Kwong KH, Kwong BYS, Lam TP, Lam ETK, Lau KW, Lui L, Ng KHL, Wong MCS, Wong TY, Yeung CF, You JHS, Yung RWH. Antibiotic management of acute pharyngitis in primary care. Hong Kong Med J 2019; 25:58-63. [PMID: 30713150 DOI: 10.12809/hkmj187544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The Centre for Health Protection of the Department of Health has convened the Advisory Group on Antibiotic Stewardship Programme in Primary Care (the Advisory Group) to formulate guidance notes and strategies for optimising judicious use of antibiotics and enhancing the Antibiotic Stewardship Programme in Primary Care. Acute pharyngitis is one of the most common conditions among out-patients in primary care in Hong Kong. Practical recommendations on the diagnosis and antibiotic treatment of acute streptococcal pharyngitis are made by the Advisory Group based on the best available clinical evidence, local prevalence of pathogens and associated antibiotic susceptibility profiles, and common local practice.
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Affiliation(s)
| | - A M W Chan
- Hong Kong College of Family Physicians, Hong Kong
| | - W W Y Au
- Infection Control Branch, Centre for Health Protection, Department of Health, Hong Kong
| | - D V K Chao
- Department of Family Medicine and Primary Health Care, United Christian Hospital, Hospital Authority, Hong Kong
| | - K Choi
- Hong Kong Medical Association, Hong Kong
| | - K W Choi
- Hong Kong Society for Infectious Diseases, Hong Kong
| | - S M Y Choi
- Primary Care Office, Department of Health, Hong Kong
| | - Y Chow
- Quality HealthCare Medical Services Limited, Hong Kong
| | - C Y M Fan
- Professional Development and Quality Assurance, Department of Health, Hong Kong
| | - P L Ho
- IMPACT Editorial Board, Reducing bacterial resistance with IMPACT, 5th edition, Hong Kong
| | - E M T Hui
- Department of Family Medicine, New Territories East Cluster, Hospital Authority, Hong Kong
| | - K H Kwong
- Human Health Holdings Limited, Hong Kong
| | - B Y S Kwong
- Chief Pharmacist's Office, Hospital Authority, Hong Kong
| | - T P Lam
- Department of Family Medicine and Primary Care, The University of Hong Kong, Hong Kong
| | - E T K Lam
- Centre for Health Protection Infection Control Branch, Department of Health, Hong Kong
| | - K W Lau
- Centre for Health Protection Infection Control Branch, Department of Health, Hong Kong
| | - L Lui
- Centre for Health Protection Infection Control Branch, Department of Health, Hong Kong
| | - K H L Ng
- Centre for Health Protection Infection Control Branch, Department of Health, Hong Kong
| | - M C S Wong
- Hong Kong Academy of Medicine, Hong Kong
| | - T Y Wong
- Centre for Health Protection Infection Control Branch, Department of Health, Hong Kong
| | | | - J H S You
- School of Pharmacy, The Chinese University of Hong Kong, Hong Kong
| | - R W H Yung
- Hong Kong Sanatorium & Hospital, Hong Kong
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8
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Azarian T, Mitchell PK, Georgieva M, Thompson CM, Ghouila A, Pollard AJ, von Gottberg A, du Plessis M, Antonio M, Kwambana-Adams BA, Clarke SC, Everett D, Cornick J, Sadowy E, Hryniewicz W, Skoczynska A, Moïsi JC, McGee L, Beall B, Metcalf BJ, Breiman RF, Ho PL, Reid R, O’Brien KL, Gladstone RA, Bentley SD, Hanage WP. Global emergence and population dynamics of divergent serotype 3 CC180 pneumococci. PLoS Pathog 2018; 14:e1007438. [PMID: 30475919 PMCID: PMC6283594 DOI: 10.1371/journal.ppat.1007438] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 12/06/2018] [Accepted: 10/25/2018] [Indexed: 12/23/2022] Open
Abstract
Streptococcus pneumoniae serotype 3 remains a significant cause of morbidity and mortality worldwide, despite inclusion in the 13-valent pneumococcal conjugate vaccine (PCV13). Serotype 3 increased in carriage since the implementation of PCV13 in the USA, while invasive disease rates remain unchanged. We investigated the persistence of serotype 3 in carriage and disease, through genomic analyses of a global sample of 301 serotype 3 isolates of the Netherlands3-31 (PMEN31) clone CC180, combined with associated patient data and PCV utilization among countries of isolate collection. We assessed phenotypic variation between dominant clades in capsule charge (zeta potential), capsular polysaccharide shedding, and susceptibility to opsonophagocytic killing, which have previously been associated with carriage duration, invasiveness, and vaccine escape. We identified a recent shift in the CC180 population attributed to a lineage termed Clade II, which was estimated by Bayesian coalescent analysis to have first appeared in 1968 [95% HPD: 1939-1989] and increased in prevalence and effective population size thereafter. Clade II isolates are divergent from the pre-PCV13 serotype 3 population in non-capsular antigenic composition, competence, and antibiotic susceptibility, the last of which resulting from the acquisition of a Tn916-like conjugative transposon. Differences in recombination rates among clades correlated with variations in the ATP-binding subunit of Clp protease, as well as amino acid substitutions in the comCDE operon. Opsonophagocytic killing assays elucidated the low observed efficacy of PCV13 against serotype 3. Variation in PCV13 use among sampled countries was not independently correlated with the CC180 population shift; therefore, genotypic and phenotypic differences in protein antigens and, in particular, antibiotic resistance may have contributed to the increase of Clade II. Our analysis emphasizes the need for routine, representative sampling of isolates from disperse geographic regions, including historically under-sampled areas. We also highlight the value of genomics in resolving antigenic and epidemiological variations within a serotype, which may have implications for future vaccine development.
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Affiliation(s)
- Taj Azarian
- Center for Communicable Disease Dynamics, Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, United States of America
| | - Patrick K. Mitchell
- Center for Communicable Disease Dynamics, Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, United States of America
| | - Maria Georgieva
- Center for Communicable Disease Dynamics, Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, United States of America
| | - Claudette M. Thompson
- Center for Communicable Disease Dynamics, Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, United States of America
| | - Amel Ghouila
- Institut Pasteur de Tunis, LR11IPT02, Laboratory of Transmission, Control and Immunobiology of Infections (LTCII), Tunis-Belvédère, Tunisia
| | - Andrew J. Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford; NIHR Oxford Biomedical Research Centre, Centre for Clinical Vaccinology and Tropical Medicine (CCVTM), Churchill Hospital, Oxford, United Kingdom
| | - Anne von Gottberg
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
| | - Mignon du Plessis
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
| | - Martin Antonio
- Medical Research Council Unit The Gambia, Fajara, The Gambia
| | | | - Stuart C. Clarke
- Faculty of Medicine and Institute for Life Sciences and Global Health Research Institute, University of Southampton, Southampton, United Kingdom
- NIHR Southampton Biomedical Research Centre, Southampton General Hospital, Southampton, United Kingdom
| | - Dean Everett
- Queens Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Jennifer Cornick
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Ewa Sadowy
- National Medicines Institute, Warsaw, Poland
| | | | | | - Jennifer C. Moïsi
- Pfizer Vaccines, Medical Development, Scientific and Clinical Affairs, Paris, France
| | - Lesley McGee
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Bernard Beall
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Benjamin J. Metcalf
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Robert F. Breiman
- Global Health Institute, Emory University, Atlanta, Georgia, United States of America
| | - PL Ho
- Department of Microbiology, Queen Mary Hospital University of Hong Kong, Hong Kong, People’s Republic of China
| | - Raymond Reid
- Center for American Indian Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Katherine L. O’Brien
- Center for American Indian Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Rebecca A. Gladstone
- Wellcome Trust, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Stephen D. Bentley
- Wellcome Trust, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - William P. Hanage
- Center for Communicable Disease Dynamics, Department of Epidemiology, T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, United States of America
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9
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Affiliation(s)
- K Chan
- Accident and Emergency Department Queen Elizabeth Hospital, Hong Kong
| | - PL Ho
- Accident and Emergency Department Queen Elizabeth Hospital, Hong Kong
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10
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Chan K, Ho PL. Is There Any Relation between Ultrasonographic Estimation of Urinary Retention and Lower Urinary Tract Infection in Women? HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490790801500103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A study was conducted to determine whether ultrasonographic detection of urinary retention is associated with clinically suspected lower urinary tract infection (UTI). During a 6-month period (January-June 2007), women aged >16 years who presented to the emergency department of Queen Elizabeth Hospital with clinical symptoms of lower UTI were enrolled. Totally 187 patients participated and completed the study. The mean age was 50.8 ± 21.5 years. Sixty-eight (36.4%) had positive urine culture while 119 (63.6%) were negative. Defining a significant residual urine volume of greater than 50 ml had low sensitivity (17.7%) and high specificity (100%) for the detection of UTI. However, when taking into account those of smaller residual urine volume (less than 50 ml), overall 37.6% of the patients with UTI had detectable residual urine in the bladder and no significant residual urine was detected in all culture-negative patients.
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Affiliation(s)
| | - PL Ho
- Queen Mary Hospital, Department of Microbiology, University of Hong Kong, Pokfulam, Hong Kong
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Zelanis A, Menezes MC, Kitano ES, Liberato T, Tashima AK, Pinto AF, Sherman NE, Ho PL, Fox JW, Serrano SM. Proteomic identification of gender molecular markers in Bothrops jararaca venom. J Proteomics 2016; 139:26-37. [DOI: 10.1016/j.jprot.2016.02.030] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/10/2016] [Accepted: 02/24/2016] [Indexed: 01/13/2023]
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Schons-Fonseca L, da Silva JB, Milanez JS, Domingos RH, Smith JL, Nakaya HI, Grossman AD, Ho PL, da Costa RMA. Analysis of LexA binding sites and transcriptomics in response to genotoxic stress in Leptospira interrogans. Nucleic Acids Res 2016; 44:1179-91. [PMID: 26762976 PMCID: PMC4756842 DOI: 10.1093/nar/gkv1536] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 12/25/2015] [Indexed: 11/13/2022] Open
Abstract
We determined the effects of DNA damage caused by ultraviolet radiation on gene expression in Leptospira interrogans using DNA microarrays. These data were integrated with DNA binding in vivo of LexA1, a regulator of the DNA damage response, assessed by chromatin immunoprecipitation and massively parallel DNA sequencing (ChIP-seq). In response to DNA damage, Leptospira induced expression of genes involved in DNA metabolism, in mobile genetic elements and defective prophages. The DNA repair genes involved in removal of photo-damage (e.g. nucleotide excision repair uvrABC, recombinases recBCD and resolvases ruvABC) were not induced. Genes involved in various metabolic pathways were down regulated, including genes involved in cell growth, RNA metabolism and the tricarboxylic acid cycle. From ChIP-seq data, we observed 24 LexA1 binding sites located throughout chromosome 1 and one binding site in chromosome 2. Expression of many, but not all, genes near those sites was increased following DNA damage. Binding sites were found as far as 550 bp upstream from the start codon, or 1 kb into the coding sequence. Our findings indicate that there is a shift in gene expression following DNA damage that represses genes involved in cell growth and virulence, and induces genes involved in mutagenesis and recombination.
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Affiliation(s)
- Luciane Schons-Fonseca
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo 05503-900, Brazil Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo 05508-000, Brazil Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139, USA
| | - Josefa B da Silva
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo 05503-900, Brazil
| | - Juliana S Milanez
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo 05503-900, Brazil Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, São Paulo 05508-000, Brazil
| | - Renan H Domingos
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo 05503-900, Brazil
| | - Janet L Smith
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139, USA
| | - Helder I Nakaya
- Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, São Paulo 05508-000, Brazil
| | - Alan D Grossman
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139, USA
| | - Paulo L Ho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo 05503-900, Brazil
| | - Renata M A da Costa
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210580, Brazil
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Ho PL, Cheung YY, Wang Y, Lo WU, Lai ELY, Chow KH, Cheng VCC. Characterization of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae from a healthcare region in Hong Kong. Eur J Clin Microbiol Infect Dis 2016; 35:379-85. [PMID: 26740321 DOI: 10.1007/s10096-015-2550-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 12/07/2015] [Indexed: 12/21/2022]
Abstract
Carbapenem-resistant Enterobacteriaceae represents a major public health issue. This study investigated the clonality and resistance mechanisms of 92 carbapenem-resistant E. coli (n = 21) and K. pneumoniae (n = 71) isolates collected consecutively from clinical specimens and patients at high risk of carriage between 2010 and 2012 in a healthcare region in Hong Kong. Combined disk tests (CDTs) and the Carba NP test were used for phenotypic detection of carbapenemases. PCR assays were used to detect carbapenemase genes. All isolates were intermediate or resistant to at least one carbapenem. Nine (9.8 %) isolates were genotypic carbapenemase producers and included six K. pneumoniae (one ST1306/bla IMP-4, one ST889/bla IMP-4, two ST11/bla KPC-2, one ST258/bla KPC-2, one ST483/bla NDM-1) and three E. coli (one ST131/bla IMP-4, two ST744/ bla NDM-1) isolates. All nine isolates carrying carbapenemase genes could be detected by the CDTs and the Carba NP test. PCR identified bla CTX-M and bla AmpC alone or in combination in 77.8 % (7/9) and 96.4 % (80/83) of the carbapenemase-producers and non-producers, respectively. Porin loss was detected in 22.2 % (2/9) and 59.0 % (49/83) of the carbapenemase-producers and non-producers, respectively. Overall, the E. coli clones were diverse (14 different STs), but 36.6 % (26/71) of the K. pneumoniae isolates belonged to ST11. In conclusion, the prevalence of carbapenemases among carbapenem-nonsusceptible E. coli and K. pneumoniae remained low in Hong Kong. Porin loss combined with AmpC and/or CTX-M type ESBL was the major mechanism of carbapenem resistance in the study population.
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Affiliation(s)
- P L Ho
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China.
| | - Y Y Cheung
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
| | - Y Wang
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
| | - W U Lo
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
| | - E L Y Lai
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
| | - K H Chow
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
| | - V C C Cheng
- Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, SAR, People's Republic of China
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Lam TP, Lam KF, Ho PL, Yung RWH. Knowledge, attitude, and behaviour toward antibiotics among Hong Kong people: local-born versus immigrants. Hong Kong Med J 2015; 21 Suppl 7:S41-S47. [PMID: 26908273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Affiliation(s)
- T P Lam
- Department of Family Medicine and Primary Care, The University of Hong Kong
| | - K F Lam
- Department of Statistics & Actuarial Science, The University of Hong Kong
| | - P L Ho
- Department of Microbiology, The University of Hong Kong
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Cheng VCC, Chen JHK, So SYC, Wong SCY, Yan MK, Chau PH, Lee WM, To KKW, Chan JFW, Hung IFN, Ho PL, Yuen KY. Use of fluoroquinolones is the single most important risk factor for the high bacterial load in patients with nasal and gastrointestinal colonization by multidrug-resistant Acinetobacter baumannii. Eur J Clin Microbiol Infect Dis 2015; 34:2359-66. [PMID: 26373714 DOI: 10.1007/s10096-015-2489-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 09/03/2015] [Indexed: 10/23/2022]
Abstract
Gastrointestinal colonization by carbapenem-resistant Acinetobacter baumannii (CRAB) and multidrug-resistant Acinetobacter baumannii (MRAB) provides an important reservoir for clinical infections and hospital outbreaks. We conducted a 7-month study in a 3200-bed healthcare network to investigate the prevalence of gastrointestinal colonization of CRAB and MRAB in Hong Kong. Between 1 June and 31 December 2014, a total of 17,760 fecal specimens from 9469 patients were screened. Testing showed that 340 (1.9%) specimens from 224 (2.6%) patients were CRAB-positive, which included 70 (0.39%) MRAB-positive specimens from 54 (0.57%) patients. The presence of wound or ulcer, use of broad-spectrum antibiotics in the preceding 6 months, and residence in elderly homes are independent risk factors for gastrointestinal colonization of CRAB. Quantitative bacterial counts in various body sites (rectal, nasal, axilla, wound, catheterized urine, if available) were performed in 33 (61.1%) of 54 MRAB patients. Ten (30.3%) and 8 (24.2%) patients had high bacterial load (defined as over 3 log10) in rectal and nasal swabs, with a median of 5.04 log10 cfu/ml of rectal swab and 4.89 log10 cfu/ml of nasal swab in saline diluent, respectively. Nine (81.8%) of 11 patients with wounds had high bacterial load in wound swabs, with a median of 5.62 log10 cfu/ml. Use of fluoroquinolones 6 months before admission was the only significant factor associated with high bacterial load in nasal and rectal swabs. With the implementation of directly observed hand hygiene before meals and medications to all conscious hospitalized patients, no hospital outbreaks were observed during our study period.
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Affiliation(s)
- V C C Cheng
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China.,Infection Control Team, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - J H K Chen
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - S Y C So
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - S C Y Wong
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - M K Yan
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - P H Chau
- School of Nursing, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - W M Lee
- Infection Control Team, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - K K W To
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - J F W Chan
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - I F N Hung
- Department of Medicine, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - P L Ho
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - K Y Yuen
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China.
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Ho PL, Yam WC, Leung CC, Yew WW, Mok TYW, Chan KS, Tam CM. Molecular tests for rapid detection of rifampicin and isoniazid resistance in Mycobacterium tuberculosis. Hong Kong Med J 2015; 21 Suppl 4:4-7. [PMID: 26157093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023] Open
Affiliation(s)
- P L Ho
- Department of Microbiology, University of Hong Kong
| | - W C Yam
- Department of Microbiology, University of Hong Kong
| | - C C Leung
- TB and Chest Service, Department of Health
| | - W W Yew
- TB and Chest Unit, Grantham Hospital
| | - T Y W Mok
- Respiratory Medical Department, Kowloon Hospital
| | | | - C M Tam
- TB and Chest Service, Department of Health
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Cheng VCC, Lee WM, Sridhar S, Ho PL, Yuen KY. Prevention of nosocomial transmission of influenza A (H7N9) in Hong Kong. J Hosp Infect 2015; 90:355-6. [PMID: 26045132 DOI: 10.1016/j.jhin.2015.04.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 04/30/2015] [Indexed: 11/15/2022]
Affiliation(s)
- V C C Cheng
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China; Infection Control Team, Queen Mary Hospital, Hong Kong SAR, China
| | - W M Lee
- Infection Control Team, Queen Mary Hospital, Hong Kong SAR, China
| | - S Sridhar
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China
| | - P L Ho
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China
| | - K Y Yuen
- Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China.
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Giovanni DNS, Landulfo GA, Duarte LL, Santos FF, Ho PL, Mendonça RZ, Carvalho E, Junqueira-de-Azevedo ILM, Proença LAB, Barros-Battesti DM. Preliminary analysis of the transcriptome of salivary glands of Ornithodoros brasiliensis (Acari: Argasidae). BMC Proc 2014. [PMCID: PMC4211084 DOI: 10.1186/1753-6561-8-s4-p145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Rodrigues D, Farinha-Arcieri LE, Ventura AM, Chura-Chambi RM, Malavasi NV, Lemke LS, Guimarães JS, Ho PL, Morganti L. Effect of pressure on refolding of recombinant pentameric cholera toxin B. J Biotechnol 2014; 173:98-105. [PMID: 24445168 PMCID: PMC7114129 DOI: 10.1016/j.jbiotec.2013.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/04/2013] [Accepted: 12/05/2013] [Indexed: 11/16/2022]
Abstract
The production of recombinant proteins is an essential tool for the expansion of modern biological research and biotechnology. The expression of heterologous proteins in Escherichia coli often results in an incomplete folding process that leads to the accumulation of inclusion bodies (IB), aggregates that hold a certain degree of native-like secondary structure. High hydrostatic pressure (HHP) impairs intermolecular hydrophobic and electrostatic interactions, leading to dissociation of aggregates under non-denaturing conditions and is therefore a useful tool to solubilize proteins for posterior refolding. Cholera toxin (CT) is composed of a non-toxic pentamer of B subunits (CTB), a useful adjuvant in vaccines, and a toxic subunit A (CTA). We studied the process of refolding of CTB using HHP. HHP was shown to be effective for dissociation of CTB monomers from IB. Posterior incubation at atmospheric pressure of concentrated CTB (1mg/ml) is necessary for the association of the monomers. Pentameric CTB was obtained when suspensions of CTB IB were compressed at 2.4kbar for 16h in the presence of Tween 20 and incubated at 1bar for 120h. Soluble and biologically active pentameric CTB was obtained, with a yield of 213mg CTB/liter of culture. The experience gained in this study can be important to improve the refolding of proteins with quaternary structure.
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Affiliation(s)
- D Rodrigues
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil
| | - L E Farinha-Arcieri
- Universidade de São Paulo, Departamento de Microbiologia do Instituto de Ciências Biomédicas, São Paulo, Brazil
| | - A M Ventura
- Universidade de São Paulo, Departamento de Microbiologia do Instituto de Ciências Biomédicas, São Paulo, Brazil
| | - R M Chura-Chambi
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil
| | - N V Malavasi
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil
| | - L S Lemke
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil
| | - J S Guimarães
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil
| | - P L Ho
- Instituto Butantan, Centro de Biotecnologia, São Paulo, Brazil
| | - L Morganti
- Instituto de Pesquisas Energéticas e Nucleares - IPEN - CNEN/SP, Centro de Biotecnologia, São Paulo, Brazil.
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Fonseca LS, da Silva JB, Milanez JS, Monteiro-Vitorello CB, Momo L, de Morais ZM, Vasconcellos SA, Marques MV, Ho PL, da Costa RMA. Leptospira interrogans serovar copenhageni harbors two lexA genes involved in SOS response. PLoS One 2013; 8:e76419. [PMID: 24098496 PMCID: PMC3789691 DOI: 10.1371/journal.pone.0076419] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 08/28/2013] [Indexed: 11/24/2022] Open
Abstract
Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2) one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN 5CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN10TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence.
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Affiliation(s)
- Luciane S Fonseca
- Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil ; Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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Abstract
OBJECTIVE The clinical features of patients with psoas abscess in a local setting, including the microbiology, incidence and aetiologies, have not been well described. This study aimed to review such clinical features and patient outcomes. DESIGN Retrospective case series. SETTING Regional hospital, Hong Kong. PATIENTS Adults (aged ≥18 years) with psoas abscess admitted to Tuen Mun Hospital from 1 January 2006 to 31 December 2010 were included. The clinical presentations, aetiologies, microbiology, treatments, hospital stays, intensive care unit admissions, and outcomes of these patients were reviewed. RESULTS The series entailed 42 patients, five of whom developed their psoas abscess after admission and seven were intravenous drug abusers. The most common presenting symptom in community-onset cases was back, hip, or thigh pain (43% [16/37]). Fever was present at presentation in 41% (15/37) of these patients, four of whom presented with fever only. The diagnosis was made by computed tomography in 95% (40/42) of these cases. In all, 23 abscesses were considered secondary; the most common aetiology being infective spondylitis or spondylodiscitis. The commonest causative organism for a primary psoas abscess was methicillin-sensitive Staphylococcus aureus, while for secondary abscesses they were more commonly from the gastro-intestinal and genitourinary tracts. Overall in-hospital mortality rate was 14% (6/42). Secondary psoas abscess patients had longer hospital stays (mean, 62 vs 34 days; P=0.007). CONCLUSION Psoas abscess is an uncommon condition. Most patients presented with only non-specific symptoms leading to difficulty in making an early diagnosis. In more than half of these patients, the psoas abscesses were secondary, the aetiology of which differed from reported overseas experience.
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Affiliation(s)
- O F Wong
- Department of Anaesthesia and Intensive Care, Tuen Mun Hospital, Tuen Mun, New Territories, Hong Kong
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Lima FA, Miyaji EN, Quintilio W, Raw I, Ho PL, Oliveira MLS. Pneumococcal Surface Protein A does not affect the immune responses to a combined diphtheria tetanus and pertussis vaccine in mice. Vaccine 2013; 31:2465-70. [PMID: 23541622 DOI: 10.1016/j.vaccine.2013.03.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 02/06/2013] [Accepted: 03/14/2013] [Indexed: 10/27/2022]
Abstract
The Pneumococcal Surface Protein A (PspA) is a promising candidate for the composition of a protein vaccine against Streptococcus pneumoniae. We have previously shown that the whole cell Bordetella pertussis vaccine (wP) is a good adjuvant to PspA, inducing protective responses against pneumococcal infection in mice. In Brazil, wP is administered to children, formulated with diphtheria and tetanus toxoids (DTPw) and aluminum hydroxide (alum) as adjuvant. A single subcutaneous dose of PspA5-DTPlow (a formulation containing PspA from clade 5 and a new generation DTPw, containing low levels of B. pertussis LPS and Alum) induced high levels of systemic anti-PspA5 antibodies in mice and conferred protection against respiratory lethal challenges with two different pneumococcal strains. Here we evaluate the mucosal immune responses against PspA5 as well as the immune responses against the DTP antigens in mice vaccinated with PspA5-DTPlow. Subcutaneous immunization of mice with PspA5-DTPlow induced high levels of anti-PspA5 IgG in the airways but no IgA. In addition, no differences in the influx of cells to the respiratory mucosa, after the challenge, were observed in vaccinated mice, when compared with control mice. The levels of circulating anti-pertussis, -tetanus and -diphtheria antibodies were equivalent in mice vaccinated with DTPlow or PspA5-DTPlow. Antibodies induced by DTPlow or PspA5-DTPlow showed similar ability to neutralize the cytotoxic effects of the diphtheria toxin on Vero cells. Furthermore, combination with PspA5 did not affect protection against B. pertussis and tetanus toxin challenges in mice. Our results support the proposal for a combined PspA-DTP vaccine.
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Affiliation(s)
- Fernanda A Lima
- Centro de Biotecnologia, Instituto Butantan, São Paulo, SP, Brazil
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Ho PL, Chan J, Lo WU, Law PY, Li Z, Lai EL, Chow KH. Dissemination of plasmid-mediated fosfomycin resistance fosA3 among multidrug-resistant Escherichia coli from livestock and other animals. J Appl Microbiol 2012; 114:695-702. [PMID: 23216653 DOI: 10.1111/jam.12099] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/29/2012] [Accepted: 12/04/2012] [Indexed: 11/27/2022]
Abstract
AIMS To investigate plasmid-mediated fosfomycin resistance related to fosA3 in Escherichia coli isolates collected from different animals in Hong Kong, China, 2008-2010. METHODS AND RESULTS In total, 2106 faecal specimens from 210 cattle, 214 pigs, 460 chickens, 398 stray cats, 368 stray dogs and 456 wild rodents were cultured. The faecal colonization rates of fosfomycin-resistant E. coli were as follows: 11.2% in pigs, 8.6% in cattle, 7.3% in chickens, 2.4% in dogs, 0.8% in cats and 1.5% in rodents. The cultures yielded 1693 isolates of which 831 were extended-spectrum β-lactamases (ESBL) producers. Fosfomycin-resistant isolates were more likely than fosfomycin-susceptible isolates to be producers of ESBL and to have resistance to chloramphenicol, ciprofloxacin, cotrimoxazole, gentamicin and tetracycline. Of the 101 fosfomycin-resistant isolates, 97 (96.0%) isolates were fosA3 positive and 94 (93.1%) were bla(CTX) (-M) positive. PCR mapping showed that the fosA3-containing regions were flanked by IS26, both upstream and downstream in 81 (83.5%) isolates, and by an upstream bla(CTX-M-14) -containing transposon-like structure (ΔISEcp1-bla(CTX-M-14) -ΔIS903 or ISEcp1-IS10 -bla(CTX-M-14) -ΔIS903) and a downstream IS26 in 14 (14.4%) isolates. For the remaining two isolates, fosA3 was flanked by a downstream IS26 but the upstream part cannot be defined. In a random subset of 18 isolates, fosA3 was carried on transferable plasmids with sizes of 50-200 kb and the following replicons: F2:A-B- (n = 3), F16:A1:B- (n = 2), F24:A-B- (n = 1), N (n = 1), B/O (n = 1) and untypeable (n = 3). SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrates the emergence of fosA3-mediated fosfomycin resistance among multidrug-resistant E. coli isolates from various animals. IS26 transposon-like structures might be the main vehicles for dissemination of fosA3.
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Affiliation(s)
- P L Ho
- Department of Microbiology, University of Hong Kong, Pokfulam, Hong Kong, China.
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Ho PL, Chan J, Lo WU, Law PY, Chow KH. Plasmid-mediated fosfomycin resistance in Escherichia coli isolated from pig. Vet Microbiol 2012; 162:964-967. [PMID: 23078751 DOI: 10.1016/j.vetmic.2012.09.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 09/21/2012] [Accepted: 09/22/2012] [Indexed: 10/27/2022]
Abstract
Previous studies have reported plasmid-mediated fosA3 among Escherichia coli originating from human and companion animals. In this study, the plasmid, designated pHK23a originating from a multidrug-resistant E. coli isolate recovered from a slaughter pig in December 2008 in Hong Kong, China was sequenced. In conjugation, the plasmid readily transferred to E. coli J53 at high frequencies. It belongs to the narrow host range IncFII incompatibility group and is 73,607 bp in length. Sequence alignment showed that pHK23a has a 59.1 kb backbone which shares high homology with the prototype R100 plasmid and a 14.5 kb variable region. The variable region includes three genes mediating antimicrobial resistance (fosA3, Δbla(TEM-1), bla(CTX-M-3)), ten mobile genetic elements (four copies of IS26, insA, ΔinsB, ΔTn2, IS1, ΔISEcp1, Δintl1), the tir transfer inhibition protein, the pemI/pemK addiction system and eight ORFs of unknown functions (orf1, orf2, Δorf3, orf20, orf23, orf24, ycdA and ycdB). The three resistance genes were organized in a novel IS26-composite transposon-like structure. In conclusion, this is the first report of fosA3 containing plasmid in an isolate of pig origin. Since IncFII plasmids spread efficiently in Enterobacteriaceae, the detection of fosA3 with bla(CTX-M) is worrisome and might become a public health concern.
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Affiliation(s)
- P L Ho
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China; Carol Yu Center for Infection, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China.
| | - Jane Chan
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China
| | - W U Lo
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China
| | - Pierra Y Law
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China
| | - K H Chow
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, China
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Vadesilho CFM, Ferreira DM, Moreno AT, Chavez-Olortegui C, Machado de Avila RA, Oliveira MLS, Ho PL, Miyaji EN. Characterization of the antibody response elicited by immunization with pneumococcal surface protein A (PspA) as recombinant protein or DNA vaccine and analysis of protection against an intranasal lethal challenge with Streptococcus pneumoniae. Microb Pathog 2012; 53:243-9. [PMID: 22981893 DOI: 10.1016/j.micpath.2012.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 08/27/2012] [Accepted: 08/29/2012] [Indexed: 11/28/2022]
Abstract
Pneumococcal surface protein A (PspA) is an important candidate for a vaccine against pneumococcal infections. DNA vaccines expressing PspA were shown to protect mice against intraperitoneal and colonization challenge models in mice. We now show that a DNA vaccine expressing PspA from clade 4 (pSec-pspA4Pro) is also able to elicit protection against an intranasal lethal challenge model at levels similar to the recombinant protein PspA4Pro adjuvanted with alum. PspA4Pro + alum induced an IgG response characterized by a high IgG1/IgG2a ratio, leading to a lack of binding of anti-PspA IgG2a antibodies to intact pneumococci in vitro, which is in contrast to the response elicited by pSec-pspA4Pro. Epitopes recognized by the sera were mapped and antibodies induced by immunization with PspA4Pro + alum showed positive reaction with several synthetic peptides, mostly located in the first half of the protein. On the other hand, antibodies induced by the DNA vaccine showed reactivity with only two peptides. Though both strategies were protective against the intranasal lethal challenge model, the elicited humoral responses differ significantly, with the detection of important differences in the Fc (IgG1/IgG2a ratios) and Fab (recognized epitopes) regions of the induced antibodies.
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Affiliation(s)
- Cintia F M Vadesilho
- Centro de Biotecnologia, Instituto Butantan, Av Vital Brasil, 1500, 05503-900, São Paulo, SP, Brazil
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Ching ATC, Paes Leme AF, Zelanis A, Rocha MMT, Furtado MDFD, Silva DA, Trugilho MRO, da Rocha SLG, Perales J, Ho PL, Serrano SMT, Junqueira-de-Azevedo ILM. Venomics profiling of Thamnodynastes strigatus unveils matrix metalloproteinases and other novel proteins recruited to the toxin arsenal of rear-fanged snakes. J Proteome Res 2012; 11:1152-62. [PMID: 22168127 DOI: 10.1021/pr200876c] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Rear-fanged and aglyphous snakes are usually considered not dangerous to humans because of their limited capacity of injecting venom. Therefore, only a few studies have been dedicated to characterizing the venom of the largest parcel of snake fauna. Here, we investigated the venom proteome of the rear-fanged snake Thamnodynastes strigatus , in combination with a transcriptomic evaluation of the venom gland. About 60% of all transcripts code for putative venom components. A striking finding is that the most abundant type of transcript (∼47%) and also the major protein type in the venom correspond to a new kind of matrix metalloproteinase (MMP) that is unrelated to the classical snake venom metalloproteinases found in all snake families. These enzymes were recently suggested as possible venom components, and we show here that they are proteolytically active and probably recruited to venom from a MMP-9 ancestor. Other unusual proteins were suggested to be venom components: a protein related to lactadherin and an EGF repeat-containing transcript. Despite these unusual molecules, seven toxin classes commonly found in typical venomous snakes are also present in the venom. These results support the evidence that the arsenals of these snakes are very diverse and harbor new types of biologically important molecules.
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Affiliation(s)
- Ana T C Ching
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brazil, 1500, São Paulo, SP, 05503-900, Brazil
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Zelanis A, Tashima AK, Pinto AFM, Paes Leme AF, Stuginski DR, Furtado MF, Sherman NE, Ho PL, Fox JW, Serrano SMT. Bothrops jararaca venom proteome rearrangement upon neonate to adult transition. Proteomics 2011; 11:4218-28. [PMID: 21928397 DOI: 10.1002/pmic.201100287] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 06/28/2011] [Accepted: 08/08/2011] [Indexed: 11/11/2022]
Abstract
The pharmacological activities displayed by Bothrops jararaca venom undergo a significant ontogenetic shift. Similarly, the diet of this species changes from ectothermic prey in early life to endothermic prey in adulthood. In this study we used large and representative newborn and adult venom samples consisting of pools from 694 and 110 specimens, respectively, and demonstrate a significant ontogenetic shift in the venom proteome complexity of B. jararaca. 2-DE coupled to MS protein identification showed a clear rearrangement of the toxin arsenal both in terms of the total proteome, as of the glycoproteome. N-glycosylation seems to play a key role in venom protein variability between newborn and adult specimens. Upon the snake development, the subproteome of metalloproteinases undergoes a shift from a P-III-rich to a P-I-rich profile while the serine proteinase profile does not vary significantly. We also used isobaric tag labeling (iTRAQ) of venom tryptic peptides for the first time to examine the quantitative changes in the venom toxins of B. jararaca upon neonate to adult transition. The iTRAQ analysis showed changes in various toxin classes, especially the proteinases. Our study expands the in-depth understanding of venom complexity variation particularly with regard to toxin families that have been associated with envenomation pathogenesis.
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Affiliation(s)
- André Zelanis
- Laboratório Especial de Toxinologia Aplicada-CAT/cepid, Instituto Butantan, Brazil
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Miyaji EN, Carvalho E, Oliveira MLS, Raw I, Ho PL. Trends in adjuvant development for vaccines: DAMPs and PAMPs as potential new adjuvants. Braz J Med Biol Res 2011; 44:500-13. [PMID: 21584443 DOI: 10.1590/s0100-879x2011007500064] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 04/18/2011] [Indexed: 11/22/2022]
Abstract
Aluminum salts have been widely used in vaccine formulations and, after their introduction more than 80 years ago, only few vaccine formulations using new adjuvants were developed in the last two decades. Recent advances in the understanding of how innate mechanisms influence the adaptive immunity opened up the possibility for the development of new adjuvants in a more rational design. The purpose of this review is to discuss the recent advances in this field regarding the attempts to determine the molecular basis and the general mechanisms underlying the development of new adjuvants, with particular emphasis on the activation of receptors of innate immune recognition. One can anticipate that the use of these novel adjuvants will also provide a window of opportunities for the development of new vaccines.
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Affiliation(s)
- E N Miyaji
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil 1500, São Paulo, SP, Brazil
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Corrêa-Netto C, Junqueira-de-Azevedo IDLM, Silva DA, Ho PL, Leitão-de-Araújo M, Alves MLM, Sanz L, Foguel D, Zingali RB, Calvete JJ. Snake venomics and venom gland transcriptomic analysis of Brazilian coral snakes, Micrurus altirostris and M. corallinus. J Proteomics 2011; 74:1795-809. [PMID: 21515432 DOI: 10.1016/j.jprot.2011.04.003] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Revised: 04/01/2011] [Accepted: 04/04/2011] [Indexed: 11/26/2022]
Abstract
The venom proteomes of Micrurus altirostris and M. corallinus were analyzed by combining snake venomics and venom gland transcriptomic surveys. In both coral snake species, 3FTx and PLA(2) were the most abundant and diversified toxin families. 33 different 3FTxs and 13 PLA(2) proteins, accounting respectively for 79.5% and 13.7% of the total proteins, were identified in the venom of M. altirostris. The venom of M. corallinus comprised 10 3FTx (81.7% of the venom proteome) and 4 (11.9%) PLA(2) molecules. Transcriptomic data provided the full-length amino acid sequences of 18 (M. altirostris) and 10 (M. corallinus) 3FTxs, and 3 (M. altirostris) and 1 (M. corallinus) novel PLA(2) sequences. In addition, venom from each species contained single members of minor toxin families: 3 common (PIII-SVMP, C-type lectin-like, L-amino acid oxidase) and 4 species-specific (CRISP, Kunitz-type inhibitor, lysosomal acid lipase in M. altirostris; serine proteinase in M. corallinus) toxin classes. The finding of a lipase (LIPA) in the venom proteome and in the venom gland transcriptome of M. altirostris supports the view of a recruitment event predating the divergence of Elapidae and Viperidae more than 60 Mya. The toxin profile of both M. altirostris and M. corallinus venoms points to 3FTxs and PLA(2) molecules as the major players of the envenoming process. In M. altirostris venom, all major, and most minor, 3FTxs display highest similarity to type I α-neurotoxins, suggesting that these postsynaptically acting toxins may play the predominant role in the neurotoxic effect leading to peripheral paralysis, respiratory arrest, and death. M. corallinus venom posesses both, type I α-neurotoxins and a high-abundance (26% of the venom proteome) protein of subfamily XIX of 3FTxs, exhibiting similarity to bucandin from Malayan krait, Bungarus candidus, venom, which enhances acetylcholine release presynaptically. This finding may explain the presynaptic neurotoxicity of M. corallinus venom and the lack of this effect in M. altirostris venom. The anti-Micrurus (corallinus and frontalis) antivenom produced by Instituto Butantan quantitatively immunodepleted the minor toxins from M. altirostris and M. corallinus venoms but showed impaired crossreactivity towards their major 3FTx and PLA(2) molecules. The structural diversity of 3FTxs among Micrurus sp. may underlay the impaired cross-immunoreactivity of the Butantan antivenom towards M. altirostris and M. corallinus toxins, hampering the possibility to raise an antivenom against a simple venom mixture exhibiting paraspecific neutralization of other Micrurus venoms.
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Affiliation(s)
- Carlos Corrêa-Netto
- Instituto de Bioquímica Médica, Programa de Biologia Estrutural and Instituto Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Brazil
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Ho PL, Lo WU, Wong RCW, Yeung MK, Chow KH, Que TL, Tong AHY, Bao JYJ, Lok S, Wong SSY. Complete sequencing of the FII plasmid pHK01, encoding CTX-M-14, and molecular analysis of its variants among Escherichia coli from Hong Kong. J Antimicrob Chemother 2011; 66:752-6. [PMID: 21393220 DOI: 10.1093/jac/dkr010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES We characterized plasmids encoding CTX-M-14 β-lactamase originating from Escherichia coli isolates recovered from patients with uncomplicated cystitis or individuals with faecal colonization in Hong Kong from 2002 to 2004. METHODS Plasmids carrying CTX-M-14 were studied by conjugation, replicon typing, S1 nuclease-PFGE and plasmid PCR-restriction fragment length polymorphism (RFLP). The complete sequence of pHK01, a 70 kb plasmid encoding CTX-M-14 from an E. coli strain, was determined and the results compared with reference plasmids and aligned with GenBank data. RESULTS The blaCTX-M-14 plasmids could be transferred in 23 of 44 E. coli strains tested. Among the 23 transconjugants, the replicon types of the CTX-M-14-encoding plasmid were FII (n=13), I1-Iγ (n=4), F1B (n=2), FII and I1-Iγ (n=1), K (80 kb, n=1) and undetermined (n=2). Plasmid pHK01 (FII replicon) shares a high degree of homology with R100 except mainly for a 11 kb variable region containing blaCTX-M-14 (with an upstream ISEcp1 and a downstream truncated IS903), an iron transport system, an outer membrane protein (malB, maltoporin) and a putative toxin-antitoxin plasmid stability system (yacABC). It was highly related to blaCTX-M-14 (pKF3-70) and blaCTX-M-24 (pEG356) plasmids reported from mainland China in 2006 and Vietnam in 2007, respectively. Subtyping by a plasmid PCR-RFLP scheme showed that 10 of the 13 FII plasmids originating from isolates collected by multiple laboratories exhibited either identical or highly similar profiles. CONCLUSIONS This study showed that narrow host-range FII plasmids play important roles in the dissemination of CTX-M-14. FII plasmids closely related to pHK01 have disseminated widely in the Hong Kong community.
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Affiliation(s)
- P L Ho
- Department of Microbiology, University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong, People's Republic of China.
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Ho PL, Yuen KY, Lam RMK, Kam KM. Antimicrobial resistance among uropathogens causing cystitis in women. Hong Kong Med J 2011; 17 Suppl 2:21-23. [PMID: 21368330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Affiliation(s)
- P L Ho
- Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong SAR, China.
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Bezerra da Silva J, Carvalho E, Hartskeerl RA, Ho PL. Erratum to: Evaluation of the Use of Selective PCR Amplification of LPS Biosynthesis Genes for Molecular Typing of Leptospira at the Serovar Level. Curr Microbiol 2011. [DOI: 10.1007/s00284-010-9772-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cheng VCC, Tai JWM, Chan WM, Lau EHY, Chan JFW, To KKW, Li IWS, Ho PL, Yuen KY. Sequential introduction of single room isolation and hand hygiene campaign in the control of methicillin-resistant Staphylococcus aureus in intensive care unit. BMC Infect Dis 2010; 10:263. [PMID: 20822509 PMCID: PMC2944349 DOI: 10.1186/1471-2334-10-263] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Accepted: 09/07/2010] [Indexed: 02/04/2023] Open
Abstract
Background After renovation of the adult intensive care unit (ICU) with installation of ten single rooms, an enhanced infection control program was conducted to control the spread of methicillin-resistant Staphylococcus aureus (MRSA) in our hospital. Methods Since the ICU renovation, all patients colonized or infected with MRSA were nursed in single rooms with contact precautions. The incidence of MRSA infection in the ICU was monitored during 3 different phases: the baseline period (phase 1); after ICU renovation (phase 2) and after implementation of a hand hygiene campaign with alcohol-based hand rub (phase 3). Patients infected with extended spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella species were chosen as controls because they were managed in open cubicles with standard precautions. Results Without a major change in bed occupancy rate, nursing workforce, or the protocol of environmental cleansing throughout the study period, a stepwise reduction in ICU onset nonbacteraemic MRSA infection was observed: from 3.54 (phase 1) to 2.26 (phase 2, p = 0.042) and 1.02 (phase 3, p = 0.006) per 1000-patient-days. ICU onset bacteraemic MRSA infection was significantly reduced from 1.94 (phase 1) to 0.9 (phase 2, p = 0.005) and 0.28 (phase 3, p = 0.021) per 1000-patient-days. Infection due to ESBL-producing organisms did not show a corresponding reduction. The usage density of broad-spectrum antibiotics and fluoroquinolones increased from phase 1 to 3. However a significant trend improvement of ICU onset MRSA infection by segmented regression analysis can only be demonstrated when comparison was made before and after the severe acute respiratory syndrome (SARS) epidemic. This suggests that the deaths of fellow healthcare workers from an occupational acquired infection had an overwhelming effect on their compliance with infection control measures. Conclusion Provision of single room isolation facilities and promotion of hand hygiene practice are important. However compliance with infection control measures relies largely on a personal commitment, which may increase when personal safety is threatened.
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Affiliation(s)
- Vincent C C Cheng
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
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Oliveira MLS, Miyaji EN, Ferreira DM, Moreno AT, Ferreira PCD, Lima FA, Santos FL, Sakauchi MA, Takata CS, Higashi HG, Raw I, Kubrusly FS, Ho PL. Combination of pneumococcal surface protein A (PspA) with whole cell pertussis vaccine increases protection against pneumococcal challenge in mice. PLoS One 2010; 5:e10863. [PMID: 20523738 PMCID: PMC2877721 DOI: 10.1371/journal.pone.0010863] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 05/06/2010] [Indexed: 11/18/2022] Open
Abstract
Streptococcus pneumoniae is the leading cause of respiratory acute infections around the world. In Latin America, approximately 20,000 children under 5 years of age die of pneumococcal diseases annually. Pneumococcal surface protein A (PspA) is among the best-characterized pneumococcal antigens that confer protection in animal models of pneumococcal infections and, as such, is a good alternative for the currently available conjugated vaccines. Efficient immune responses directed to PspA in animal models have already been described. Nevertheless, few low cost adjuvants for a subunit pneumococcal vaccine have been proposed to date. Here, we have tested the adjuvant properties of the whole cell Bordetella pertussis vaccine (wP) that is currently part of the DTP (diphtheria-tetanus-pertussis) vaccine administrated to children in several countries, as an adjuvant to PspA. Nasal immunization of BALB/c mice with a combination of PspA5 and wP or wP(low)--a new generation vaccine that contains low levels of B. pertussis LPS--conferred protection against a respiratory lethal challenge with S. pneumoniae. Both PspA5-wP and PspA5-wP(low) vaccines induced high levels of systemic and mucosal antibodies against PspA5, with similar profile, indicating no essential requirement for B. pertussis LPS in the adjuvant properties of wP. Accordingly, nasal immunization of C3H/HeJ mice with PspA5-wP conferred protection against the pneumococcal challenge, thus ruling out a role for TLR4 responses in the adjuvant activity and the protection mechanisms triggered by the vaccines. The high levels of anti-PspA5 antibodies correlated with increased cross-reactivity against PspAs from different clades and also reflected in cross-protection. In addition, passive immunization experiments indicated that antibodies played an important role in protection in this model. Finally, subcutaneous immunization with a combination of PspA5 with DTP(low) protected mice against challenge with two different pneumococcal strains, opening the possibility for the development of a combined infant vaccine composed of DTP and PspA.
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Affiliation(s)
- Maria Leonor S. Oliveira
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
- * E-mail: (PLH); (MLSO)
| | - Eliane N. Miyaji
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | | | - Adriana T. Moreno
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | | | - Fernanda A. Lima
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | | | | | - Célia S. Takata
- Divisão Bioindustrial, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Hisako G. Higashi
- Divisão Bioindustrial, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Isaías Raw
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Flavia S. Kubrusly
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Paulo L. Ho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
- * E-mail: (PLH); (MLSO)
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Zelanis A, Tashima AK, Rocha MMT, Furtado MF, Camargo ACM, Ho PL, Serrano SMT. Analysis of the Ontogenetic Variation in the Venom Proteome/Peptidome ofBothrops jararacaReveals Different Strategies to Deal with Prey. J Proteome Res 2010; 9:2278-91. [DOI: 10.1021/pr901027r] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cheng VCC, Chan JFW, Tai JWM, Ho YY, Li IWS, To KKW, Ho PL, Yuen KY. Successful control of vancomycin-resistant Enterococcus faecium outbreak in a neurosurgical unit at non-endemic region. Emerg Health Threats J 2010; 2:e9. [PMID: 22460290 PMCID: PMC3167649 DOI: 10.3134/ehtj.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2009] [Revised: 10/07/2009] [Accepted: 10/11/2009] [Indexed: 11/18/2022]
Abstract
Vancomycin-resistant enterococci (VRE) have emerged in many parts of the world, but have only been reported sporadically in Hong Kong. We report an outbreak of vancomycin-resistant Enterococcus faecium (VREfm) in a neurosurgical unit at a tertiary teaching hospital between 3 March and 3 April 2009 in Hong Kong. During the outbreak investigation, clinical samples from 193 (91.5%) of 211 patients who had stayed in the neurosurgical unit and 506 environmental samples were screened for VREfm. Besides the index case, another 3 (1.6%) out of 192 patients were found to be positive for VREfm. Two (0.4%) out of 506 environmental samples were positive for VREfm. All four clinical and two environmental isolates were found to be clonally related by pulse-field gel electrophoresis. The risk factors for nosocomial acquisition of VREfm included advanced age (P=0.047), presence of nasogastric tubing (P=0.002) and tracheostomy (P<0.001), and the use of β-lactam antibiotics (P<0.001) and vancomycin (P=0.001). Contrary to other VRE outbreaks in which the spread was rapid, the neurosurgical patients' immobilization because of coma and mechanical ventilation dependency, and the vigilant practice of hand hygiene by health-care workers successfully limited the number of secondary cases despite the delayed recognition of the index case. All patients with VREfm were labeled in the hospital network information system so that stringent infection control measures with contact precautions would be carried out once these patients were readmitted to prevent its spread in our locality.
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Affiliation(s)
- V C C Cheng
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China
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Ferreira DM, Oliveira MLS, Moreno AT, Ho PL, Briles DE, Miyaji EN. Protection against nasal colonization with Streptococcus pneumoniae by parenteral immunization with a DNA vaccine encoding PspA (Pneumococcal surface protein A). Microb Pathog 2010; 48:205-13. [PMID: 20206678 DOI: 10.1016/j.micpath.2010.02.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 02/19/2010] [Accepted: 02/25/2010] [Indexed: 11/15/2022]
Abstract
Pneumococcal surface protein A (PspA) is an important candidate for a cost-effective vaccine with broad coverage against Streptococcus pneumoniae. We have previously shown that intramuscular immunization with PspA as a DNA vaccine induces an immune response characterized by the induction of a balanced IgG1/IgG2a antibody response in BALB/c mice, which was able to efficiently mediate complement deposition onto intact bacteria and to induce protection against an intraperitoneal challenge. We now confirm the results in C57BL/6 mice and further show that the response induced by the DNA vaccine expressing PspA is able to mediate protection against colonization of the nasopharyngeal mucosa even though immunization was given parenterally. Moreover, a positive correlation was observed between IgG1 and the numbers of CFU recovered, whereas an inverse correlation was observed between nasal CFU levels and IgG2a. A positive correlation was also found for IgG1/IgG2a antibody ratios with CFU recovered from the nasopharynx. Therefore, reduction of nasal colonization was strongly associated with increased levels of serum IgG2a complement fixing antibody and low levels of IgG1 antibody which has much less complement fixing activity. Passive transfer of serum from animals immunized with the DNA vaccine expressing PspA was also able to reduce the fraction of mice with high density of colonization of the nasopharynx. Secretion of IFN-gamma, but not IL-17, was observed in splenocytes from mice immunized with the DNA vaccine.
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Affiliation(s)
- Daniela M Ferreira
- Centro de Biotecnologia, Instituto Butantan, Av Vital Brasil, 1500, 05503-900, São Paulo, SP, Brazil
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Cheng VCC, Tai JWM, Wong LMW, Chan JFW, Li IWS, To KKW, Hung IFN, Chan KH, Ho PL, Yuen KY. Prevention of nosocomial transmission of swine-origin pandemic influenza virus A/H1N1 by infection control bundle. J Hosp Infect 2010; 74:271-7. [PMID: 20061056 PMCID: PMC7118838 DOI: 10.1016/j.jhin.2009.09.009] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 09/04/2009] [Indexed: 02/04/2023]
Abstract
After the outbreak of severe acute respiratory syndrome in Hong Kong, the importance of preventing nosocomial transmission of respiratory viruses has become a top priority in infection control. During the containment and early mitigation phases of the swine-origin influenza virus (S-OIV) A H1N1 pandemic, an infection control bundle consisting of multiple coherent measures was organised by our infection control team to minimise nosocomial transmission. This included repeated open staff forum achieving high attendance; early recognition of index cases among inpatients by liberal testing; early relief of sick staff from work; directly observed hand hygiene practice during outbreaks; and monitoring of compliance with infection control practice. During the first 100 days (from 1 May to 8 August 2009) when the first 100 laboratory-confirmed patients with S-OIV and 12 infected healthcare workers (HCWs) were identified, a total of 836 asymptomatic exposed persons (184 patients and 652 HCWs) were required to undergo a seven-day medical surveillance. The infection control nurses monitored them for the onset of symptoms. Four (0.48%) exposed persons (one house officer, two non-clinical staff, and one patient) were virologically confirmed with S-OIV. Not wearing a surgical mask either by the exposed persons during contact with the index cases (4/4 vs 264/832, P = 0.010) or vice versa (4/4 vs 300/832, P = 0.017, Fisher's exact test) were found to be significant risk factors for nosocomial acquisition of S-OIV.
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Affiliation(s)
- V C C Cheng
- Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China
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Wong HT, Que TL, Ho PL. What Have We Learnt from Bacterial Stool Culture Results? a Retrospective Study of Hospitalised Gastroenteritis Cases in a Regional Hospital in Hong Kong. HONG KONG J EMERG ME 2010. [DOI: 10.1177/102490791001700105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background Stool culture is one of the common investigations done for patients with gastroenteritis, and fluoroquinolones have been used frequently for suspected bacterial gastroenteritis. Objective To study the yield of bacterial pathogens in stool culture in a local regional hospital for in-patients with gastroenteritis and the individual pathogens identified. Also, the value of stool culture and the prescription of fluoroquinolones as empirical antibiotics were reviewed. Methods This was a retrospective study. All in-patients with the principal diagnosis of “gastroenteritis” in the year 2007 were reviewed. We excluded pregnant patients and patients under 18 years of age. Patients were divided into two age groups and data were analysed including demographics, clinical findings, admission time and culture results. Antibiotics prescription behaviour was also analysed. Results A total of 837 adult patients fulfilled the criteria. Among them, 562 cases had their stool saved and sent for bacterial culture. Eighty-nine cases were found to have their stool cultures positive for bacteria. The identified pathogens were namely Vibrio parahaemolyticus (38.2%), Salmonella species (34.8%), Campylobacter species (11.2%), Plesiomonas species (10.1%) and Aeromonas species (3.4%) respectively. The yield of positive stool culture was 15.8%. Conclusion Vibrio parahaemolyticus and Salmonella species were still the most common pathogens for bacterial gastroenteritis among hospitalized patients in Hong Kong, especially in the young and middle aged. Their occurrence followed a seasonal pattern. Physicians had a tendency to prescribe fluoroquinolones for cases with fever and travel history. Also, the problem of antibiotic resistance did exist. It is important for practitioners to follow local guidelines before ordering microbiological investigations on stool and prescribing empirical antibiotic treatment.
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Affiliation(s)
| | - TL Que
- Tuen Mun Hospital, Department of Clinical Pathology, Tsing; Chung Koon Road, Tuen Mun, N.T., Hong Kong
| | - PL Ho
- The University of Hong Kong, Department of Microbiology and Centre of Infection, Pokfulam Road, Hong Kong
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Ho PL, Yam WC, Tsang KWT, Lai WM. Detection and characterisation of extended-spectrum beta-lactamases among blood stream isolates of Enterobacter species in Hong Kong. Hong Kong Med J 2009; 15 Suppl 9:4-5. [PMID: 20393215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
1. Extended-spectrum beta-lactamase(ESBL) resistance in Enterobacter spp may be under-recognised. 2. Detection methods for ESBL resistance in Enterobacter spp may need to be modified.
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Affiliation(s)
- P L Ho
- Department of Microbiology, The University of Hong Kong, Queen Mary Hospital Compound, Pokfulam Road, Hong Kong SAR, China.
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Ho PL, Chuang SK, Choi YF, Lee RA, Lit A, Ng TK, Que TL, Shek KC, Tong HK, Tse WS, Tung WK, Yung RW. Community-associated methicillin-resistant Staphylococcus aureus skin and soft tissue infections in Hong Kong. Hong Kong Med J 2009; 15 Suppl 9:9-11. [PMID: 20393217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
Community-associated methicillin resistant Staphylococcus aureus is an emerging cause of skin and soft tissue infections in Hong Kong, especially among certain ethnic minorities.
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Affiliation(s)
- P L Ho
- Department of Microbiology, The University of Hong Kong, Queen Mary Hospital Compound, Pokfulam Road, Hong Kong SAR, China.
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Ho PL, Yuen KY, Tse WS, Ng TK, Que TL, Lai E, Yung RW. Molecular epidemiology of community-associated methicillin-resistant Staphylococcus aureus. Hong Kong Med J 2009; 15 Suppl 9:6-8. [PMID: 20393216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
1. Community-associated methicillin-resistant Staphylococcus aureus (MRSA) strains with diverse genetic backgrounds are emerging in Hong Kong. 2. Intra-familial spread of community-associated MRSA is common.
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Affiliation(s)
- P L Ho
- Department of Microbiology, The University of Hong Kong, Queen Mary Hospital Compound, Pokfulam Road, Hong Kong SAR, China.
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Batista IFC, Ramos OHP, Ventura JS, Junqueira-de-Azevedo ILM, Ho PL, Chudzinski-Tavassi AM. A new Factor Xa inhibitor from Amblyomma cajennense with a unique domain composition. Arch Biochem Biophys 2009; 493:151-6. [PMID: 19853573 DOI: 10.1016/j.abb.2009.10.009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 10/14/2009] [Accepted: 10/17/2009] [Indexed: 11/19/2022]
Abstract
Bioactive compounds of great interest are found in the saliva of hematophagous organisms. While exploring a cDNA library derived from the salivary glands of the tick Amblyomma cajennense, a transcript that codes for a protein with unique structure (containing an N-terminal Kunitz-type domain and a C-terminus with no homology to any annotated sequences) was found. The recombinant mature form of this protein ( approximately 13.5kDa) was produced in Escherichia coli BL21 (DE3), and it was able to inhibit Factor Xa (FXa) and extend global blood clotting times in vitro and ex vivo. Static and dynamic predictions of its tertiary structure indicate regions that may be related to its FXa inhibitor function.
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Affiliation(s)
- I F C Batista
- Laboratório de Bioquímica e Biofísica, Instituto Butantan, Av. Vital Brasil, São Paulo, SP, Brazil
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Carvalho E, Barbosa AS, Gómez RM, Oliveira MLS, Romero EC, Gonçales AP, Morais ZM, Vasconcellos SA, Ho PL. Evaluation of the expression and protective potential of Leptospiral sphingomyelinases. Curr Microbiol 2009; 60:134-42. [PMID: 19826861 DOI: 10.1007/s00284-009-9519-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 09/24/2009] [Indexed: 11/25/2022]
Abstract
Leptospirosis is a zoonotic disease of global distribution, which affects both animals and humans. Pathogenic leptospires, the bacteria that cause this disease, require iron for their growth, and these spirochetes probably use their hemolysins, such as the sphingomyelinases, as a way to obtain this important nutrient from host red blood cells during infection. We expressed and purified the leptospiral sphingomyelinases Sph1, Sph2, Sph4, and SphH in a heterologous system. However, the recombinant proteins were not able to lyse sheep erythrocytes, despite having regular secondary structures. Transcripts for all sphingomyelinases tested were detected by RT-PCR analyses, but only Sph2 and SphH native proteins could be detected in Western blot assays using Leptospira whole extracts as well as in renal tubules of infected hamsters. Moreover, antibodies present in the serum of a human patient with laboratory-confirmed leptospirosis recognized Sph2, indicating that this sphingomyelinase is expressed and exposed to the immune system during infection in humans. However, in an animal challenge model, none of the sphingomyelinases tested conferred protection against leptospirosis.
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Affiliation(s)
- Eneas Carvalho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, SP, Brazil
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Li IWS, Chan KH, To KWK, Wong SSY, Ho PL, Lau SKP, Woo PCY, Tsoi HW, Chan JFW, Cheng VCC, Zheng BJ, Chen H, Yuen KY. Differential susceptibility of different cell lines to swine-origin influenza A H1N1, seasonal human influenza A H1N1, and avian influenza A H5N1 viruses. J Clin Virol 2009; 46:325-30. [PMID: 19801200 DOI: 10.1016/j.jcv.2009.09.013] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 08/27/2009] [Accepted: 09/10/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND The novel swine-origin influenza A H1N1 virus (S-OIV) causes the current pandemic. Its tissue tropism and replication in different cell lines are not well understood. OBJECTIVE Compare the growth characteristics of cell lines infected by S-OIV, seasonal influenza A H1N1 (sH1N1) and avian influenza A H5N1 (H5N1) viruses and the effect of temperature on viral replication. STUDY DESIGN Cytopathic effect (CPE), antigen expression by immunofluorescence (IF) and viral load profile by quantitative RT-PCR in 17 cell lines infected by S-OIV, sH1N1 and H5N1 were examined. Comparison of their replication efficiency in chick embryo was performed. The effect of temperature on viral replication in Madin-Darby canine kidney (MDCK) cells was determined by TCID(50) at 33 degrees C, 37 degrees C and 39 degrees C for 5 consecutive days. RESULTS S-OIV replicated in cell lines derived from different tissues or organs and host species with comparable viral load to sH1N1. Among 13 human cell lines tested, Caco-2 has the highest viral load for S-OIV. S-OIV showed a low viral load with no CPE or antigen expression in pig kidney cell PK-15, H5N1 demonstrated the most diverse cell tropism by CPE and antigen expression, and the highest viral replication efficiency in both cell lines and allantoic fluid. All three viruses demonstrated best growth at 37 degrees C in MDCK cells. CONCLUSION Cell line growth characteristics of S-OIV, sH1N1 and H5N1 appear to correlate clinically and pathologically with involved anatomical sites and severity. Low replication of S-OIV in PK-15 suggests that this virus is more adapted to human than swine.
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Affiliation(s)
- I W S Li
- Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China
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Cheng VCC, Yam WC, Chan JFW, To KKW, Ho PL, Yuen KY. Clostridium difficile ribotype 027 arrives in Hong Kong. Int J Antimicrob Agents 2009; 34:492-3. [PMID: 19464857 DOI: 10.1016/j.ijantimicag.2009.04.004] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Accepted: 04/15/2009] [Indexed: 11/27/2022]
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47
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Cheng VCC, Chan JFW, To KKW, Tai JWM, Ho PL. Detection of community-associated MRSA as a result of the unmasking effect of antibiotic treatment. J Hosp Infect 2009; 72:273-4. [PMID: 19446364 DOI: 10.1016/j.jhin.2009.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2009] [Accepted: 03/20/2009] [Indexed: 11/30/2022]
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Cheng VCC, Chan JFW, Tai JWM, Ho YY, Li IWS, To KKW, Ho PL, Yuen KY. Successful control of vancomycin-resistant Enterococcus faecium outbreak in a neurosurgical unit at non-endemic region. Emerging Health Threats Journal 2009. [DOI: 10.3402/ehtj.v2i0.7089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- VCC Cheng
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
- Infection Control Unit, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - JFW Chan
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
| | - JWM Tai
- Infection Control Unit, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - YY Ho
- Infection Control Unit, Queen Mary Hospital, Hong Kong Special Administrative Region, China
| | - IWS Li
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
| | - KKW To
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
| | - PL Ho
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
| | - KY Yuen
- Carol Yu Centre for Infection, Queen Mary Hospital, Hong Kong Special Administrative Region, China; and
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Carvalho E, Barbosa AS, Gómez RM, Cianciarullo AM, Hauk P, Abreu PA, Fiorini LC, Oliveira MLS, Romero EC, Gonçales AP, Morais ZM, Vasconcellos SA, Ho PL. Leptospiral TlyC is an extracellular matrix-binding protein and does not present hemolysin activity. FEBS Lett 2009; 583:1381-5. [PMID: 19328790 DOI: 10.1016/j.febslet.2009.03.050] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 03/10/2009] [Accepted: 03/21/2009] [Indexed: 12/31/2022]
Abstract
The role of TlyA, TlyB and TlyC proteins in the biology of Leptospira is still uncertain. Although these proteins have been considered as putative hemolysins, we demonstrate that leptospiral recombinant TlyB and TlyC do not possess hemolytic activity. However, further experiments showed that TlyC is a surface-exposed protein that seems to bind to laminin, collagen IV and fibronectin. The expression of both proteins was detected both in vitro and in vivo. Our findings suggest that TlyB and TlyC are not directly involved in hemolysis, and that TlyC may contribute to Leptospira binding to extracellular matrix (ECM) during host infection.
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Affiliation(s)
- Eneas Carvalho
- Centro de Biotecnologia, Instituto Butantan, 05503-900 São Paulo - SP, Brazil
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50
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Leão LI, Ho PL, Junqueira-de-Azevedo IDLM. Transcriptomic basis for an antiserum against Micrurus corallinus (coral snake) venom. BMC Genomics 2009; 10:112. [PMID: 19291316 PMCID: PMC2662881 DOI: 10.1186/1471-2164-10-112] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 03/16/2009] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Micrurus corallinus (coral snake) is a tropical forest snake belonging to the family Elapidae. Its venom shows a high neurotoxicity associated with pre- and post-synaptic toxins, causing diaphragm paralysis, which may result in death. In spite of a relatively small incidence of accidents, serum therapy is crucial for those bitten. However, the adequate production of antiserum is hampered by the difficulty in obtaining sufficient amounts of venom from a small snake with demanding breeding conditions. In order to elucidate the molecular basis of this venom and to uncover possible immunogens for an antiserum, we generated expressed sequences tags (ESTs) from its venom glands and analyzed the transcriptomic profile. In addition, their immunogenicity was tested using DNA immunization. RESULTS A total of 1438 ESTs were generated and grouped into 611 clusters. Toxin transcripts represented 46% of the total ESTs. The two main toxin classes consisted of three-finger toxins (3FTx) (24%) and phospholipases A(2) (PLA(2)s) (15%). However, 8 other classes of toxins were present, including C-type lectins, natriuretic peptide precursors and even high-molecular mass components such as metalloproteases and L-amino acid oxidases. Each class included an assortment of isoforms, some showing evidence of alternative splicing and domain deletions. Five antigenic candidates were selected (four 3FTx and one PLA(2)) and used for a preliminary study of DNA immunization. The immunological response showed that the sera from the immunized animals were able to recognize the recombinant antigens. CONCLUSION Besides an improvement in our knowledge of the composition of coral snake venoms, which are very poorly known when compared to Old World elapids, the expression profile suggests abundant and diversified components that may be used in future antiserum formulation. As recombinant production of venom antigens frequently fails due to complex disulfide arrangements, DNA immunization may be a viable alternative. In fact, the selected candidates provided an initial evidence of the feasibility of this approach, which is less costly and not dependent on the availability of the venom.
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Affiliation(s)
- Luciana I Leão
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, 05503-900, São Paulo, SP, Brazil
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, SP, Brazil
| | - Paulo L Ho
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, 05503-900, São Paulo, SP, Brazil
| | - Inacio de LM Junqueira-de-Azevedo
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, 05503-900, São Paulo, SP, Brazil
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, SP, Brazil
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