RESUMEN
BACKGROUND: The immune responses mediated by CD8+T cells are known to be significant in controlling M. tuberculosis infections. In order to determine the role of cytotoxic CD8+T cells in the protective immune mechanism in latently infected subjects, this study examined whether or not the cytotoxic immune responses of CD8+T cells specific to the M. tuberculosis somatic antigens are induced in BCG vaccinated healthy subjects. METHODS: Cytotoxicity and IFN-gamma elispot assays were used to investigate the activities of CD8+T cells specific for the thyA30-38 peptide epitope in circulating peripheral blood mononuclear cells (PBMC) from BCG-vaccinated HLA-A*0201 and A*0206 subjects. RESULTS: The results indicate the cytotoxic and IFN-gamma immune responses of CD8+T cells specific for thyA30-38 were induced in BCG vaccinated healthy subjects. CONCLUSION: The cytotoxic and IFN-gamma responses by CD8+T cells specific for the M. tuberculosis somatic antigens are induced in BCG-vaccinated subjects, and appear to be involved in the protective immune mechanism in latently infected people against a M. tuberculosis infection.