RESUMO
BACKGROUND: Although European Borrelia burgdorferi sensu lato isolates have been divided into five genospecies, specific tools for the serotype characterization of only three genospecies are available. Monoclonals antibodies (mAbs) H3TS, D6 and I17.3 identify B. burgdorferi sensu stricto (ss.), B. garinii and B. afzelii respectively, but no mAbs are available to identify B. valaisiana. In the same way, specific primers exist to amplify the OspA gene of B. burgdorferi ss., B. garinii and B. afzelii. The aim of the study was to develop species-specific mAb and PCR primers for the phenotypic and genetic identification of B. valaisiana. RESULTS: This study describes a mAb that targets OspA of B. valaisiana and primers targeting the OspA gene of this species. As the monoclonal antibody A116k did not react with strains NE231, M7, M53 and Frank and no amplification was observed with strains NE231, M7 and M53, the existence of two subgroups among European B. valaisiana species was confirmed. CONCLUSIONS: The association of both monoclonal antibody A116k and primers Bval 1F and Bval 1R allows to specific identification of the B. valaisiana isolates belonging to subgroup 1.
Assuntos
Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Borrelia/classificação , Genótipo , Lipoproteínas , Fenótipo , Anticorpos Monoclonais , Antígenos de Superfície/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Técnicas de Tipagem Bacteriana , Vacinas Bacterianas , Borrelia/genética , Borrelia/isolamento & purificação , Primers do DNA , Variação Genética , Doença de Lyme/microbiologia , Reação em Cadeia da PolimeraseRESUMO
OBJECTIVE: To test the performances of new Borrelia garinii immunoblots specific for Borrelia burgdorferi sensu lato with a selected panel of sera from patients with various clinical presentations of Lyme borreliosis. METHODS: In order to establish the sensitivity and the specificity of these immunoblots, we tested serum samples obtained from patients with early- and late-stage Lyme disease (erythema migrans n=35, neuroborreliosis n=61, acrodermatitis chronica atrophicans (ACA) n=27 and arthritis n=41), from patients with diagnoses and laboratory findings associated with serologic cross-reactivity to Lyme disease (syphilis n=12, Epstein-Barr infection n=9, autoimmune markers n=29) and from blood donors residing in regions of low and medium endemicity (n=80, n=100). RESULTS: The combined sensitivity (IgG and IgM) of the tests was 90% for patients with erythema migrans, 92% for neuroborreliosis, 96% for ACA and 100% for Lyme arthritis. The specificity of the IgG immunoblot was 94%, and that of the IgM immunoblot was 97%, taking into account the prevalence of borrelia antibodies in the overall population. Interpretation of these immunoblots is based on scores allocated to different specific borrelia antigens. CONCLUSIONS: The Western blot technology is extremely useful in dissecting the immune response to borrelia infections, which develops gradually over a period of weeks to years and which involves the appearance of IgM and IgG antibodies directed against a number of borrelia-associated proteins.