Identification of Mycobacterium tuberculosis CTL epitopes restricted by HLA-A*0201 in HHD mice.
CD8 T cells are thought to play an important role in protective immunity to tuberculosis. The major histocompatibility complex class I subtype HLA-A*0201 is one of the most prevalent class I alleles, with a frequency of over 30% in most populations. HLA-A*0201 transgenic, H-2D(b)/mouse beta2-microglobulin double-knockout mice (HHD) which express human HLA-A*0201 but no mouse class 1, was shown to provide a powerful model for studying induction of HLA-A*0201-restricted immune responses in vivo.



HHD mice were immunized with plasmid DNA encoding MPB51 by using a gene gun, and IFN-gamma production from the immune spleen cells was analyzed in response to a synthetic overlapping peptide library covering the mature MPB51 sequence. catatonic T lymphocytes (CTL) activity was measured using cytotoxicity assay and the three-color flowcytometry was used to reveal IFN-gamma-producing immune spleen cells.



Our findings were shown that only one peptide, p51-70, appeared to stimulate the immune splenocytes to produce IFN-gamma. Flow cytometric analysis with intracellular IFN-gamma and the T-cell phenotype revealed that the p51-70 peptide contains an immunodominant CD8+ T-cell epitope. Further analysis with computer-assisted algorithms permitted identification of a T-cell nona mer epitope, p54-62. Finally, we proved that the p54-62/HLA-A*0201 complex is strongly recognized by HLA class I-restricted CD8+ MPB5 1-specific CTL cells.



These results suggest that vaccination with MPB51 gene elicited MPB51-specific CTL. In addition, the P54-62 epitope thus represent potential subunit component for the design of vaccines against tuberculosis.
Dept. of Immunology and Microbiology, Sari Medical School, Mazandaran University of Medical Science, Mazandaran, Iran.
Alireza
A
Rafiei
Dept.  of Immunology and cell Biology, Medical Faculty of Hamamatsu University, Japan.
Yiukito
Y
Kiutade
D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004269:DNA, Bacterial / Q000235:genetics; D000939:Epitopes / Q000235:genetics; D005260:Female; D015234:HLA-A Antigens / Q000235:genetics / Q000378:metabolism*; D015789:HLA-A2 Antigen; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D008212:Lymphocyte Depletion; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D032581:Tuberculosis Vaccines / Q000235:genetics / Q000276:immunology; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000517:prevention & control; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology
D000942:Antigens, Bacterial; D004269:DNA, Bacterial; D000939:Epitopes; D015234:HLA-A Antigens; C435939:HLA-A*02:01 antigen; D015789:HLA-A2 Antigen; D032581:Tuberculosis Vaccines; D019444:Vaccines, DNA; D007371:Interferon-gamma