| Full text | |
| Author(s): Show less - |
de Barros, Samar Freschi
[1, 2]
;
De Amicis, Karine Marafigo
[1, 2]
;
Alencar, Raquel
[1, 2]
;
Smeesters, Pierre Robert
[3, 4]
;
Trunkel, Ariel
[1, 2]
;
Postol, Edilberto
[1, 2]
;
Almeida Junior, Joao Nobrega
[5]
;
Rossi, Flavia
[5]
;
Campos Pignatari, Antonio Carlos
[6]
;
Kalil, Jorge
[7, 1, 2]
;
Guilherme, Luiza
[1, 2, 8]
Total Authors: 11
|
| Affiliation: | [1] Univ Sao Paulo, Sch Med, Heart Inst InCor, BR-01246000 Sao Paulo - Brazil
[2] Natl Inst Sci & Technol, Inst Immunol Invest, BR-01246000 Sao Paulo - Brazil
[3] Univ Libre Bruxelles, Fac Sci, Inst Biol & Med Mol, Lab Genet & Physiol Bacterienne, B-1050 Brussels - Belgium
[4] Murdoch Childrens Res Inst, Parkville, Vic 3052 - Australia
[5] Univ Sao Paulo, Sch Med, Clin Hosp, Microbiol Lab, BR-01246000 Sao Paulo - Brazil
[6] Univ Fed Sao Paulo, Special Clin Microbiol Lab LEMC, UNIFESP, Sao Paulo - Brazil
[7] Univ Sao Paulo, Sch Med, Div Clin Immunol & Allergy, BR-01246000 Sao Paulo - Brazil
[8] Heart Inst HC FMUSP, Clin Hosp, Immunol Lab, BR-05403000 Sao Paulo - Brazil
Total Affiliations: 8
|
| Document type: | Journal article |
| Source: | BMC INFECTIOUS DISEASES; v. 15, AUG 5 2015. |
| Web of Science Citations: | 6 |
| Abstract | |
Background: Several human diseases are caused by Streptococcus pyogenes, ranging from common infections to autoimmunity. Characterization of the most prevalent strains worldwide is a useful tool for evaluating the coverage capacity of vaccines under development. In this study, a collection of S. pyogenes strains from Sao Paulo, Brazil, was analyzed to describe the diversity of strains and assess the vaccine coverage capacity of StreptInCor. Methods: Molecular epidemiology of S. pyogenes strains was performed by emm-genotyping the 229 isolates from different clinical sites, and PCR was used for superantigen profile analysis. The emm-pattern and tissue tropism for these M types were also predicted and compared based on the emm-cluster classification. Results: The strains were fit into 12 different emm-clusters, revealing a diverse phylogenetic origin and, consequently, different mechanisms of infection and escape of the host immune system. Forty-eight emm-types were distinguished in 229 samples, and the 10 most frequently observed types accounted for 69 % of all isolates, indicating a diverse profile of circulating strains comparable to other countries under development. A similar proportion of E and A-C emm-patterns were observed, whereas pattern D was less frequent, indicating that the strains of this collection primarily had a tissue tropism for the throat. In silico analysis of the coverage capacity of StreptInCor, an M protein-conserved regionally based vaccine candidate developed by our group, had a range of 94.5 % to 59.7 %, with a mean of 71.0 % identity between the vaccine antigen and the predicted amino acid sequence of the emm-types included here. Conclusions: This is the first report of S. pyogenes strain characterization in Sao Paulo, one of the largest cities in the world; thus, the strain panel described here is a representative sample for vaccine coverage capacity analysis. Our results enabled evaluation of StreptInCor candidate vaccine coverage capacity against diverse M-types, indicating that the vaccine candidate likely would induce protection against the diverse strains worldwide. (AU) | |