使用未经治疗的HIV-1感染的长期幸存者的外周血单核细胞(PBMC)研究了HIV-1和FIVp24蛋白序列上的交叉反应肽(LTS;>10年的感染,ART),未接受ART的短期HIV-1感染受试者,和ART治疗的HIV-1感染受试者。使用重叠的HIV-1和FIVp24肽,用PBMC进行IFNγ-ELISpot和CFSE-增殖分析。通过IFNγ或T细胞增殖分析,超过一半的受HIV-1感染的受试者(22/31或71%)对一个或多个FIVp24肽库应答。来自所有3个HIV(+)组中的感染受试者的PBMC和T细胞主要通过IFNγ产生识别一个FIVp24肽池(Fp14),并且通过T细胞增殖分析识别一个额外的FIVp24肽池(Fp9)。此外,对重叠SIVp24肽序列的评估,在SIV的Fp14/Hp15对应物上鉴定出保守表位,Sp14,但在SIV的Fp9上没有,Sp9对这些FIV肽库的响应是高度可再现的,并且在2-4年的监测中持续存在。细胞毒素的细胞内染色分析和CD107a的表型分析确定来自Fp9和Fp14库的肽表位诱导细胞毒性T淋巴细胞相关分子,包括穿孔素,颗粒酶B,颗粒酶A,和/或CD107a的表达。选定的FIV和HIV-1感染患者识别的相应SIV表位表明,这些蛋白质序列在SIV和HIV-1上都是进化上保守的(例如,Hp15:Fp14:Sp14)。这些研究表明,HIV-1,FIV的比较免疫原性分析,和SIV可以识别进化保守的T细胞相关慢病毒表位,可用作预防或免疫疗法的疫苗。
Cross-reactive peptides on HIV-1 and FIV p24 protein sequences were studied using peripheral blood mononuclear cells (PBMC) from untreated HIV-1-infected long-term survivors (LTS; >10 y of infection without antiretroviral therapy, ART), short-term HIV-1 infected subjects not on ART, and ART-treated HIV-1 infected subjects. IFNγ-ELISpot and CFSE-proliferation analyses were performed with PBMC using overlapping HIV-1 and FIV p24 peptides. Over half of the HIV-1 infected subjects tested (22/31 or 71%) responded to one or more FIV p24 peptide pools by either IFNγ or T-cell proliferation analysis. PBMC and T cells from infected subjects in all 3 HIV(+) groups predominantly recognized one FIV p24 peptide pool (Fp14) by IFNγ production and one additional FIV p24 peptide pool (Fp9) by T-cell proliferation analysis. Furthermore, evaluation of overlapping SIV p24 peptide sequences identified conserved epitope(s) on the Fp14/Hp15-counterpart of SIV, Sp14, but none on Fp9-counterpart of SIV, Sp9. The responses to these FIV peptide pools were highly reproducible and persisted throughout 2-4 y of monitoring. Intracellular staining analysis for cytotoxins and phenotyping for CD107a determined that peptide epitopes from Fp9 and Fp14 pools induced cytotoxic T lymphocyte-associated molecules including perforin, granzyme B, granzyme A, and/or expression of CD107a. Selected FIV and corresponding SIV epitopes recognized by HIV-1 infected patients indicate that these protein sequences are evolutionarily conserved on both SIV and HIV-1 (e.g., Hp15:Fp14:Sp14). These studies demonstrate that comparative immunogenicity analysis of HIV-1, FIV, and SIV can identify evolutionarily-conserved T cell-associated lentiviral epitopes, which could be used as a vaccine for prophylaxis or immunotherapy.