RESUMO
Cytotoxic T lymphocytes (CTLs) play an important role in the immunity of Mycobacterium tuberculosis (Mtb) infection. In the present study, the identification of novel CTL epitopes from efflux pumps, Rv1258c and Rv1410c, was reported. Candidate native peptides and their analogues were predicted with prediction programs. Rv1410c-p510 (TLAPQVEPL) and Rv1410c-p510-1Y9V (YLAPQVEPV) showed potent binding affinity and stability towards HLA-A*0201 molecule. In enzyme-linked immunospot (ELISPOT) assay, the CTLs induced from peripheral blood mononuclear cells (PBMCs) by these peptides could release interferon-γ (IFN-γ) in at least one healthy donor (HLA-A*02(+), PPD(+)). In cytotoxicity assay in vitro and in vivo, the CTLs induced by Rv1410c-p510-1Y9V could specifically lyse peptide-loaded T2 cells. This is the first report to identify CTL epitopes from the efflux pumps of Mtb. The novel epitope identified could serve as candidate to the multivalent peptide vaccine against drug-resistant M. tuberculosis.
Assuntos
Epitopos de Linfócito T/metabolismo , Mycobacterium tuberculosis/imunologia , Linfócitos T Citotóxicos/metabolismo , Vacinas contra a Tuberculose , Tuberculose/imunologia , Transportadores de Cassetes de Ligação de ATP/síntese química , Transportadores de Cassetes de Ligação de ATP/imunologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Bactérias/síntese química , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Linhagem Celular , Simulação por Computador , Citotoxicidade Imunológica , ELISPOT , Mapeamento de Epitopos , Epitopos de Linfócito T/imunologia , Antígeno HLA-A2/metabolismo , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Proteínas de Membrana Transportadoras/síntese química , Proteínas de Membrana Transportadoras/imunologia , Proteínas de Membrana Transportadoras/metabolismo , Mycobacterium tuberculosis/patogenicidade , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Tuberculose/prevenção & controleRESUMO
CFP21 is a major secreted protein of Mycobacterium tuberculosis (Mtb) which is considered as a promising antigen for immunotherapy. To identify CFP21-derived HLA-A*0201 restricted epitopes, a series of native peptides and their analogues were predicted with prediction programs and synthesized. The native peptide, p134 (AVADHVAAV), and its analogues, p134-1Y2L and p134-1Y2L9L, showed potent binding affinity and stability to HLA-A*0201 molecule. In ELISPOT assay, the cytotoxic T lymphocytes (CTLs) induced by these peptides could release IFN-γ. In cytotoxicity assay, the CTLs induced by p134 and p134-1Y2L9L could specifically lyse peptide-loaded T2 cells. In these two assays, the native peptide, p134, showed the most potent activity. Our results indicated that p134 could be a novel epitope which could serve as a good candidate to develop peptide vaccines against M. tuberculosis.