OBJECTIVETo characterize the Gag-Specific T lymphocyte responses and identify immunodominant region recognized in Chinese HIV-1 recombinant subtype B/C infectors.

METHODS10 antiretroviral treatment (ART) naive HIV-1 recombinant subtype B/C infectors with infected time in 1 year, 25 ART-naive infectors with infected time > 3 years and 10 HIV-1-seronegative healthy individuals were enrolled. HIV-1-specific T lymphocyte responses were analyzed by an IFN-gamma Elispot assay against 123 overlapping peptides spanning HIV-1 Gag protein in the present study.

RESULTSGag-specific T lymphocyte responses of interferon-gamma secretion were identified in 8(8/10) Chinese HIV-1 recombinant subtype B/ C infectors with infected time in 1 year, the specific T lymphocytes are mainly targeted at five seperated peptides. Responses were identified in 17(68%) infectors with infected time more than 3 years, the specific T lymphocytes are mainly targeted at one peptide in p17 and six in p24. There was obviously positive correlation (P = 0.0318, r = 0.519) between the magnitude of responses and viremia in infectors infected time > 3 years. The magnitude of response in infectors infected in 1 year was significantly higher than group infected time > 3 years (P = 0.021). None of healthy individuals produced positive responses.

CONCLUSIONSHIV-1 recombinant subtype B/C Infectors at different stages of diseases recognize different region of gag.