摘要
Background Man who has sex with man （MSM） is one of the high risk groups for spreading HIV/AIDS. It was reported that the most prevalent human irnmunodeficiency virus type 1 （HIV-1） strain among MSM is subtype B; however, T cell immunity remains unknown across the HIV-1 B genome in this population. Methods Using Elispot assay with synthetic peptides spanning the sequence of HIV-1 consensus B, HIV-l-specific cytotoxic T-cell lymphocyte responses were quantified among 3 treated and 19 untreated HIV-1 infected MSM from Beijing, China. Cross-sectional association between viral loads and cellular immune responses were analyzed. Results Peptide pools corresponding to each HIV-1 protein were used for Env, Gag, Pol, Nef, Tat/Rev, Vpr/Vpu and Vif. The results showed that the magnitude of T cell responses in the 3 treated HIV^＋ MSM group [median, 770 spot forming cells （SFCs） per 106 peripheral blood mononuclear cells （PBMCs）] might be significantly lower than that in the 19 untreated HIV^＋ MSM group （median, 6175 SFCs per 106 PBMCs）. Nef, Gag and Pol are the most frequently targeted HIV-1 antigens; and 16 subjects （73%） were identified with vigorous T cell immunity against each of these three proteins. The overall magnitude of T cell immunity closely related to its breadth （r=-0.72, P〈0.05） and was inversely but weakly associated with viral loads （r=-0.15）. Further analysis showed that both Gag （r=-0.24） and Pol specific T cells （r=-0.12） contributed to this inverse association whereas Nef specific T cells showed no association with viral loads. Conclusions The magnitude of HIV-1 specific T cells is inversely but weakly associated with viral loads among MSM; HIV-specific T cell responses against conservative sequences （Gag and Pol） are the main contributors to this association among Chinese HIV^＋ MSM. These findings have important implications for vaccine design.
Background Man who has sex with man （MSM） is one of the high risk groups for spreading HIV/AIDS. It was reported that the most prevalent human irnmunodeficiency virus type 1 （HIV-1） strain among MSM is subtype B; however, T cell immunity remains unknown across the HIV-1 B genome in this population. Methods Using Elispot assay with synthetic peptides spanning the sequence of HIV-1 consensus B, HIV-l-specific cytotoxic T-cell lymphocyte responses were quantified among 3 treated and 19 untreated HIV-1 infected MSM from Beijing, China. Cross-sectional association between viral loads and cellular immune responses were analyzed. Results Peptide pools corresponding to each HIV-1 protein were used for Env, Gag, Pol, Nef, Tat/Rev, Vpr/Vpu and Vif. The results showed that the magnitude of T cell responses in the 3 treated HIV^＋ MSM group [median, 770 spot forming cells （SFCs） per 106 peripheral blood mononuclear cells （PBMCs）] might be significantly lower than that in the 19 untreated HIV^＋ MSM group （median, 6175 SFCs per 106 PBMCs）. Nef, Gag and Pol are the most frequently targeted HIV-1 antigens; and 16 subjects （73%） were identified with vigorous T cell immunity against each of these three proteins. The overall magnitude of T cell immunity closely related to its breadth （r=-0.72, P〈0.05） and was inversely but weakly associated with viral loads （r=-0.15）. Further analysis showed that both Gag （r=-0.24） and Pol specific T cells （r=-0.12） contributed to this inverse association whereas Nef specific T cells showed no association with viral loads. Conclusions The magnitude of HIV-1 specific T cells is inversely but weakly associated with viral loads among MSM; HIV-specific T cell responses against conservative sequences （Gag and Pol） are the main contributors to this association among Chinese HIV^＋ MSM. These findings have important implications for vaccine design.
基金
This study was supported by the grant from the Ministry of Science and Technology of China (No. 2004BA719A01).
