Profile of T and B lymphocytes in individuals resistant to Schistosoma mansoni infection
Afiliação
(1)Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Brazil.
(2)INCT-DT-CNPQ/MCT), Instituto Nacional de Ciência E Tecnologia Em Doenças Tropicais, Brazil.
(3)Departamento de Bioquímica E Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
(4)Centro das Ciências Biológicas E da Saúde, Universidade Federal Do Oeste da Bahia, Barreiras, BA, Brazil.
(5)Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (FIOCRUZ), Salvador, Bahia, Brazil.
(6)Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
(7)INCT-DT-CNPQ/MCT), Instituto Nacional de Ciência E Tecnologia Em Doenças Tropicais, Salvador, BA, Brazil.
(8)Departamento de Análises Clínicas E Toxicológicas, Faculdade de Farmácia, UFBA, Salvador, BA, Brazil.
Resumo
The mechanisms involved in the development of resistance to infection/reinfection by Schistosoma mansoni still arouse great interest and controversy. Some authors demonstrate that resistance to infection is attributed to a mixed Th1 and Th2 response and resistance to reinfection after repeated treatments through mechanisms associated with the Th2 response. Through flow cytometry, the phenotypic characterization of B and T lymphocytes in individuals residing in endemic areas with low parasite loads over 10 years was evaluated for the first time in humans. In this study, individuals with low parasite loads for Schistosoma mansoni had a higher proportion of Th1 and Th2 cells. In addition, lymphocytes from these individuals showed a higher degree of expression of costimulatory molecules CD28 and CTLA-4 and regulatory molecules FoxP3 and IL-10, when compared to individuals with high parasite loads. Our data indicate that the control of the parasite load of S. mansoni must be associated with a Th1, Th2, and regulatory response, and that further studies are needed to elucidate the possibility of mechanisms associated with the hyporesponsiveness of lymphocytes from individuals with high parasite loads.