1
|
Detection of capsular genotypes of methicillin-resistant Staphylococcus aureus and clonal distribution of the cap5 and cap8 genes in clinical isolates. Arch Microbiol 2022; 204:186. [PMID: 35192046 PMCID: PMC8861481 DOI: 10.1007/s00203-022-02793-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 01/22/2022] [Accepted: 02/03/2022] [Indexed: 11/29/2022]
Abstract
Up until now, the capsular polysaccharides of Staphylococcus aureus have been classified into 11 types, of which only 2 types 5 and 8; (encoded by the genes cap5 and cap8, respectively) are present in 80–90% of clinically significant strains. The aim of the present study was to detect the capsular genotypes of methicillin-resistant S. aureus (MRSA) clinical isolates and determined their clonal distribution. A total of 262 MRSA clinical isolates from different hospitals in Mexico were analyzed by PCR to determine the genetic characteristics of their capsule expression. Pulsed-field gel electrophoresis and multilocus sequence typing were used to characterize the isolates. The analysis of the capsular genotypes among MRSA isolates showed that 245 isolates (93.5%) contained the cap5 gene, and that the remaining 17 (6.5%) encoded the cap8 gene. The MRSA isolates were grouped into four clonal groups. The identification of the capsular genotypes of clinical isolates of MRSA is important information because potential vaccine formulations against S. aureus involve capsular polysaccharides.
Collapse
|
2
|
Rainard P, Gilbert FB, Germon P, Foucras G. Invited review: A critical appraisal of mastitis vaccines for dairy cows. J Dairy Sci 2021; 104:10427-10448. [PMID: 34218921 DOI: 10.3168/jds.2021-20434] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/23/2021] [Indexed: 11/19/2022]
Abstract
Infections of the mammary gland remain a frequent disease of dairy ruminants that negatively affect animal welfare, milk quality, farmer serenity, and farming profitability and cause an increase in use of antimicrobials. There is a need for efficacious vaccines to alleviate the burden of mastitis in dairy farming, but this need has not been satisfactorily fulfilled despite decades of research. A careful appraisal of past and current research on mastitis vaccines reveals the peculiarities but also the commonalities among mammary gland infections associated with the major mastitis pathogens Escherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, or Streptococcus dysgalactiae. A major pitfall is that the immune mechanisms of effective protection have not been fully identified. Until now, vaccine development has been directed toward the generation of antibodies. In this review, we drew up an inventory of the main approaches used to design vaccines that aim at the major pathogens for the mammary gland, and we critically appraised the current and tentative vaccines. In particular, we sought to relate efficacy to vaccine-induced defense mechanisms to shed light on some possible reasons for current vaccine shortcomings. Based on the lessons learned from past attempts and the recent results of current research, the design of effective vaccines may take a new turn in the years to come.
Collapse
Affiliation(s)
- Pascal Rainard
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France.
| | - Florence B Gilbert
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France
| | - Pierre Germon
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France
| | - Gilles Foucras
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Toulouse, École Nationale Vétérinaire de Toulouse, Interactions Hôtes-Agents Pathogènes, 31076 Toulouse, France
| |
Collapse
|
3
|
Abdi RD, Dunlap JR, Gillespie BE, Ensermu DB, Almeida RA, Kerro Dego O. Comparison of Staphylococcus aureus surface protein extraction methods and immunogenicity. Heliyon 2019; 5:e02528. [PMID: 31687478 PMCID: PMC6820086 DOI: 10.1016/j.heliyon.2019.e02528] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 07/05/2019] [Accepted: 09/24/2019] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus is the major contagious bovine mastitis pathogen and has no effective vaccine. Strain variation and limited knowledge of common immunogenic antigen/s are among major constraints for developing effective vaccines. S. aureus cell surface proteins that are exposed to the host immune system constitute good vaccine candidates. The objective of this study was to compare two novel S. aureus surface protein extraction methods with biotinylation method and evaluate immune-reactivity of extracted proteins. Surface proteins were extracted from nine genetically distinct S. aureus strains from cases of bovine mastitis. After extraction, bacterial cell integrity was examined by Gram staining and electron microscopy to determine if extraction methods caused damage to cells that may release non-surface proteins. The extracted proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and evaluated for immune-reactivity using western blot. Results showed that all three extraction methods provided multiple protein bands on SDS-PAGE. Western blot result showed several immunoreactive surface proteins, in which some proteins strongly (well-resolved, thick, dark, and intense band) reacted across the nine strains tested. The three methods are valid for the extraction of surface proteins and hexadecane, and cholic acid methods are more feasible than biotinylation since both are easier, cheaper, and have minor effects on the bacterial cell. Strongly immune-reactive surface proteins may serve as potential candidates for a vaccine to control S. aureus mastitis in dairy cows.
Collapse
Affiliation(s)
- Reta Duguma Abdi
- Department of Animal Science, The University of Tennessee, Knoxville, TN37966, United States
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, Long Island University, Greenvale, NY11548, United States
| | - John R. Dunlap
- Joint Institute for Advanced Materials (JIAM) Microscopy Center and Advanced Microscopy and Imaging Center, The University of Tennessee, Knoxville, TN, 37996, United States
| | - Barbara E. Gillespie
- Department of Animal Science, The University of Tennessee, Knoxville, TN37966, United States
| | - Desta Beyene Ensermu
- Department of Animal Science, The University of Tennessee, Knoxville, TN37966, United States
| | - Raul Antonio Almeida
- Department of Animal Science, The University of Tennessee, Knoxville, TN37966, United States
| | - Oudessa Kerro Dego
- Department of Animal Science, The University of Tennessee, Knoxville, TN37966, United States
- Corresponding author.
| |
Collapse
|
4
|
Han S, Yu H, Yang F, Qiao S, He P. Effect of dietary supplementation with hyperimmunized hen egg yolk powder on diarrhoea incidence and intestinal health of weaned pigs. FOOD AGR IMMUNOL 2019. [DOI: 10.1080/09540105.2019.1581732] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Shuaijuan Han
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, College of Animal Science and Technology, China Agricultural University, Beijing, People’s Republic of China
| | - Haitao Yu
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, College of Animal Science and Technology, China Agricultural University, Beijing, People’s Republic of China
| | - Fengfan Yang
- Hubei Shendi Biological Technology Co., LTD, Jingmen, People’s Republic of China
| | - Shiyan Qiao
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, College of Animal Science and Technology, China Agricultural University, Beijing, People’s Republic of China
| | - Pingli He
- State Key Laboratory of Animal Nutrition, Ministry of Agriculture Feed Industry Centre, College of Animal Science and Technology, China Agricultural University, Beijing, People’s Republic of China
| |
Collapse
|
5
|
Abstract
Nosocomial or hospital-acquired infections are associated with prolonged hospitalizations and increased healthcare costs. Infections associated with surgical implants are becoming more difficult and more costly to manage, as they require repeated surgical procedures and a longer period of time to treat patients. Continued advances in the use of medical devices, an increase in the number of immunocompromised patients, and a steady rise in the prevalence of antibiotic-resistant organisms has renewed interest in the development of novel therapies that can be used to prevent and treat nosocomial infections. This review provides an overview of bacterial adhesins and focuses on novel immunological therapies developed to treat staphylococcal infections.
Collapse
Affiliation(s)
- J M Patti
- Inhibitex, Inc., Alpharetta, Georgia, USA.
| |
Collapse
|
6
|
Gogoi-Tiwari J, Babra Waryah C, Sunagar R, Veeresh HB, Nuthanalakshmi V, Preethirani PL, Sharada R, Isloor S, Bhat A, Al-Salami H, Hegde NR, Mukkur TK. Typing ofStaphylococcus aureusisolated from bovine mastitis cases in Australia and India. Aust Vet J 2015. [DOI: 10.1111/avj.12349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- J Gogoi-Tiwari
- School of Biomedical Sciences, Faculty of Health Sciences; Curtin University; Perth Western Australia Australia
| | - C Babra Waryah
- School of Biomedical Sciences, Faculty of Health Sciences; Curtin University; Perth Western Australia Australia
| | - R Sunagar
- Ella Foundation; Genome Valley, Shameerpet Mandal Hyderabad India
| | - HB Veeresh
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - V Nuthanalakshmi
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - PL Preethirani
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - R Sharada
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - S Isloor
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - A Bhat
- Veterinary College; Karnataka Veterinary, Animal and Fisheries Sciences University; Hebbal Bangalore India
| | - H Al-Salami
- School of Pharmacy, Faculty of Health Sciences; Curtin University; Perth Western Australia Australia
| | - NR Hegde
- Ella Foundation; Genome Valley, Shameerpet Mandal Hyderabad India
| | - TK Mukkur
- School of Biomedical Sciences, Faculty of Health Sciences; Curtin University; Perth Western Australia Australia
| |
Collapse
|
7
|
Middleton JR. Staphylococcus aureusantigens and challenges in vaccine development. Expert Rev Vaccines 2014; 7:805-15. [DOI: 10.1586/14760584.7.6.805] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
8
|
Immune response of heifers against a Staphylococcus aureus CP5 whole cell and lysate vaccine formulated with ISCOM Matrix adjuvant. Res Vet Sci 2013; 96:86-94. [PMID: 24210331 DOI: 10.1016/j.rvsc.2013.10.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 08/12/2013] [Accepted: 10/15/2013] [Indexed: 12/24/2022]
Abstract
Staphylococcus aureus is the most frequently isolated pathogen from bovine intramammary infections worldwide. Commercially available vaccines for mastitis control are composed either of S. aureus lysates or whole-cells formulated with traditional adjuvants. We recently showed the ability of a S. aureus CP5 whole-cell vaccine adjuvanted with ISCOM Matrix to increase specific antibodies production in blood and milk, improving opsonic capacity, compared with the same vaccine formulated with Al(OH)3. However, there is no information about the use of ISCOM Matrix for the formulation of bacterial lysates. The aim of this study was to characterize the innate and humoral immune responses induced by a S. aureus CP5 whole-cell or lysate vaccine, formulated with ISCOM Matrix after immunization of pregnant heifers. Both immunogens stimulated strong humoral immune responses in blood and milk, raising antibodies that increased opsonic capacity. Lysate formulation generated a higher and longer lasting antibody titer and stimulated a higher expression of regulatory and pro-inflammatory cytokines compared with the whole-cell vaccine.
Collapse
|
9
|
Bandeira F, Picoli T, Zani J, Silva WD, Fischer G. Frequência de Staphylococcus aureus em casos de mastite bovina subclínica, na região Sul do Rio Grande do Sul. ARQUIVOS DO INSTITUTO BIOLÓGICO 2013. [DOI: 10.1590/s1808-16572013000100001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A mastite bovina é uma doença importante na exploração leiteira, não apenas pelas perdas econômicas diretas que promove, mas também pelas perdas indiretas e o potencial risco à saúde pública. Dentre as principais causas de infecções intramamárias, destacam-se as bactérias do gênero Staphylococcus spp., sendo que Staphylococcus aureus é o agente etiológico predominante em mastite subclínica. O objetivo desse trabalho foi verificar a frequência de mastite subclínica em oito rebanhos localizados na região Sul do Rio Grande do Sul (Brasil) e a relação da enfermidade com a presença de S. aureus. Adicionalmente, pesquisou-se a presença de S. intermedius e S. hyicus nas amostras de leite obtidas. Para identificação da doença, utilizou-se o California Mastitis Test (CMT). A identificação da espécie de Staphylococcus spp. foi feita em meio de cultura ágar Baird-Parker, com posterior confirmação das colônias suspeitas em coloração de gram, prova de catalase, pesquisa de coagulase livre e pesquisa de termonuclease. A mastite subclínica foi constatada em 53,6% dos animais testados. A presença de Staphylococcus coagulase positiva foi identificada em 12,6% dos animais com mastite subclínica. Nesses mesmos animais, a bactéria identificada como S. aureus foi o agente etiológico presente em 17,6% dos casos. Adicionalmente, pode-se perceber que, dentre o grupo identificado como coagulase positiva, 85,7% corresponderam a S. aureus, enquanto 8,5% mostraram características bioquímicas compatíveis com S. intermedius e 5,8% foram consideradas S. hyicus.
Collapse
Affiliation(s)
| | - T. Picoli
- Universidade Federal de Pelotas, Brasil
| | - J.L. Zani
- Universidade Federal de Pelotas, Brasil
| | | | | |
Collapse
|
10
|
Factores de virulencia de Staphylococcus aureus asociados con infecciones mamarias en bovinos: relevancia y rol como agentes inmunógenos. Rev Argent Microbiol 2013; 45:119-30. [DOI: 10.1016/s0325-7541(13)70011-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
11
|
Zhen YH, Jin LJ, Guo J, Li XY, Li Z, Fang R, Xu YP. Characterization of specific egg yolk immunoglobulin (IgY) against mastitis-causing Staphylococcus aureus. J Appl Microbiol 2010; 105:1529-35. [PMID: 19146490 DOI: 10.1111/j.1365-2672.2008.03920.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To evaluate the in vitro activity of egg yolk immunoglobulin (IgY) against mastitis-causing Staphylococcus aureus. METHODS AND RESULTS Specific IgY was produced by immunizing hens with formaldehyde-killed Staph. aureus, using a bacterial strain known to cause mastitis. The IgY, of 94% purity, was obtained from yolks by water dilution, salt precipitations, ultrafiltration and gel filtration. ELISA indicated that the IgY produced was specific to the antigen and five Staph. aureus isolates obtained from mastitic cows. The growth of Staph. aureus was inhibited by specific IgY at concentrations from 1 to 10 mg ml(-1) in a dose-dependent manner. The phagocytosis of Staph. aureus by milk macrophages was enhanced in the presence of specific IgY with the highest phagocytic percentage being 30% higher than that without IgY (P < 0.05). CONCLUSIONS The specific IgY against mastitis-causing Staph. aureus inhibited the growth of Staph. aureus and enhanced the phagocytosis of Staph. aureus by milk macrophages. SIGNIFICANCE AND IMPACT OF THE STUDY Specific IgY would be a potential treatment for bovine mastitis.
Collapse
Affiliation(s)
- Y-H Zhen
- Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian, China
| | | | | | | | | | | | | |
Collapse
|
12
|
Salicylic acid diminishes Staphylococcus aureus capsular polysaccharide type 5 expression. Infect Immun 2009; 78:1339-44. [PMID: 20008532 DOI: 10.1128/iai.00245-09] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Capsular polysaccharides (CP) of serotypes 5 (CP5) and 8 (CP8) are major Staphylococcus aureus virulence factors. Previous studies have shown that salicylic acid (SAL), the main aspirin metabolite, affects the expression of certain bacterial virulence factors. In the present study, we found that S. aureus strain Reynolds (CP5) cultured with SAL was internalized by MAC-T cells in larger numbers than strain Reynolds organisms not exposed to SAL. Furthermore, the internalization of the isogenic nonencapsulated Reynolds strain into MAC-T cells was not significantly affected by preexposure to SAL. Pretreatment of S. aureus strain Newman with SAL also enhanced internalization into MAC-T cells compared with that of untreated control strains. Using strain Newman organisms, we evaluated the activity of the major cap5 promoter, which was significantly decreased upon preexposure to SAL. Diminished transcription of mgrA and upregulation of the saeRS transcript, both global regulators of CP expression, were found in S. aureus cultured in the presence of SAL, as ascertained by real-time PCR analysis. In addition, CP5 production by S. aureus Newman was also decreased by treatment with SAL. Collectively, our data demonstrate that exposure of encapsulated S. aureus strains to low concentrations of SAL reduced CP production, thus unmasking surface adhesins and leading to an increased capacity of staphylococci to invade epithelial cells. The high capacity of internalization of the encapsulated S. aureus strains induced by SAL pretreatment may contribute to the persistence of bacteria in certain hosts.
Collapse
|
13
|
Pérez MM, Prenafeta A, Valle J, Penadés J, Rota C, Solano C, Marco J, Grilló MJ, Lasa I, Irache JM, Maira-Litran T, Jiménez-Barbero J, Costa L, Pier GB, de Andrés D, Amorena B. Protection from Staphylococcus aureus mastitis associated with poly-N-acetyl beta-1,6 glucosamine specific antibody production using biofilm-embedded bacteria. Vaccine 2009; 27:2379-86. [PMID: 19428854 DOI: 10.1016/j.vaccine.2009.02.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 02/03/2009] [Accepted: 02/04/2009] [Indexed: 11/17/2022]
Abstract
Staphylococcus aureus vaccines based on bacterins surrounded by slime, surface polysaccharides coupled to protein carriers and polysaccharides embedded in liposomes administered together with non-biofilm bacterins confer protection against mastitis. However, it remains unknown whether protective antibodies are directed to slime-associated known exopolysaccharides and could be produced in the absence of bacterin immunizations. Here, a sheep mastitis vaccination study was carried out using bacterins, crude bacterial extracts or a purified exopolysaccharide from biofilm bacteria delivered in different vehicles. This polysaccharide reacted specifically with antibodies to poly-N-acetyl-beta-1,6-glucosamine (PNAG) and not with antibodies to other capsular antigens or bacterial components. Following intra-mammary challenge with biofilm-producing bacteria, antibody production against the polysaccharide, milk bacterial counts and mastitis lesions were determined. Bacterins from strong biofilm-producing bacteria triggered the highest production of antibodies to PNAG and conferred the highest protection against infection and mastitis, compared with weak biofilm-producing bacteria and non-cellular inocula. Thus, bacterins from strong biofilm bacteria, rather than purified polysaccharide, are proposed as a cost-efficient vaccination against S. aureus ruminant mastitis.
Collapse
Affiliation(s)
- M M Pérez
- Departamento de Sanidad Animal, SIA-CITA (DGA) Ctra. de Montañana, Zaragoza, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Zhen YH, Jin LJ, Li XY, Guo J, Li Z, Zhang BJ, Fang R, Xu YP. Efficacy of specific egg yolk immunoglobulin (IgY) to bovine mastitis caused by Staphylococcus aureus. Vet Microbiol 2009; 133:317-22. [DOI: 10.1016/j.vetmic.2008.07.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 07/14/2008] [Accepted: 07/16/2008] [Indexed: 11/25/2022]
|
15
|
Zhen YH, Jin LJ, Guo J, Li XY, Lu YN, Chen J, Xu YP. Characterization of specific egg yolk immunoglobulin (IgY) against mastitis-causing Escherichia coli. Vet Microbiol 2008; 130:126-33. [DOI: 10.1016/j.vetmic.2007.12.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 12/09/2007] [Accepted: 12/10/2007] [Indexed: 10/22/2022]
|
16
|
Verdier I, Durand G, Bes M, Taylor KL, Lina G, Vandenesch F, Fattom AI, Etienne J. Identification of the capsular polysaccharides in Staphylococcus aureus clinical isolates by PCR and agglutination tests. J Clin Microbiol 2007; 45:725-9. [PMID: 17202275 PMCID: PMC1829147 DOI: 10.1128/jcm.01572-06] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is a major cause of nosocomial and community-acquired infections. The predominance of two capsular polysaccharides, types 5 and 8, on the surface of clinical isolates led to the development of a conjugate vaccine (StaphVAX) based on capsular polysaccharides types 5 and 8 conjugated to a carrier protein. We have studied the capsular phenotypes and genotypes of 195 isolates representative of all clinical syndromes that encompassed both hospital and community-acquired infections. These isolates were mainly detected in France between January 2001 and December 2004. In this population, most of clinical isolates (87%) expressed either capsular polysaccharide type 5 (42%) or 8 (45%), whereas 13% were nontypeable by the serotyping method with antibodies specific to capsular polysaccharide type 5 or 8. These 26 nontypeable strains were further serotyped and were demonstrated to express the cell wall surface antigen 336, a polyribitol phosphate N-acetylglucosamine, which resembles cell wall teichoic acid. Among methicillin-resistant Staphylococcus aureus (MRSA) strains, we found a predominance of serotype 5 for 64% of strains, whereas MSSA isolates were predominantly capsular serotype 8 (60%). All S. aureus clinical isolates included in the present study have been investigated by PCR method, demonstrating that all isolates carried either the cap5 or the cap8 locus.
Collapse
|