Evaluation of Lsa46 and Lsa77 Leptospiral Proteins for Their Immunoprotective Activities in Hamster Model of Leptospirosis

Autor(es)

Teixeira, Aline F. ; Fernandes, Luis G. V. ; Souza Filho, Antonio ; Souza, Gisele O. ; Vasconcellos, Silvio A. ; Heinemann, Marcos B. ; Nascimento, Ana L. T. O.

• Tipo de documento: Artigo Científico
• Fonte: BIOMED RESEARCH INTERNATIONAL; v. 2018, p. 13-pg., 2018-01-01.

Resumo

Leptospirosis is a neglected tropical disease caused by pathogenic Leptospira spp. The lack of an effective vaccine favors the increase of the disease. Currently, surface-exposed proteins are the main targets for the search of vaccine candidates. In this study, we examined whether the surface Lsa46 and Lsa77 proteins, previously identified as laminin and plasminogen binding proteins, have the capacity of inducing protection and sterilizing immunity against challenge with virulent Leptospira in hamster model. Animals were subcutaneously immunized with Lsa46, Lsa77, or a combination of both in Alum adjuvant and challenged intraperitoneally with L. interrogans serovar Kennewicki strain Pomona Fromm. Hamster immunization with Lsa46 or Lsa77 or both promoted a strong IgG response. Th2- and Th1-biased immune responses were observed when Lsa46 and Lsa77 were individually administered, respectively, as detected by the IgG1/IgG2/3 ratio. Immunized hamsters with the combined proteins induced a Th1-biased immune response. Although the immunization with Lsa46 and Lsa77 stimulated protective immunity with reduction of bacterial burden, when compared to animals individually immunized with the proteins, the data was not statistically significant. Thus, although promising, more studies are needed before the role of these proteins in stimulating sterilizing immunity in mammals is conclusively determined. (AU)

• Processo FAPESP: 14/50981-0 - Busca de proteínas de superfície nas sequências do genoma da Leptospira interrogans: caracterização funcional e imunológica para o entendimento de mecanismos envolvidos na patogênese de bactéria
• Beneficiário: Ana Lucia Tabet Oller do Nascimento
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/11541-0 - Avaliação do potencial vacinal de frações antigênicas obtidas em Leptospira interrogans serovar Copenhageni utilizando hamster como modelo animal
• Beneficiário: Aline Florencio Teixeira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 17/06731-8 - Aplicação de CRISPR-interferência na elucidação da patogênese da leptospirose e desenvolvimento de novas estratégias para obtenção de mutantes knockout
• Beneficiário: Luis Guilherme Virgílio Fernandes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado