HIV-1感染者CD8+T细胞受体基因多样性特点及其与病毒载量的相关性

摘要

Objective To determine the complementary determining region 3 (CDR3) length diversity of T cell receptor Vβ repertoires of CD8+ T lymphocytes and to explore its association with viral load in individuals with HIV-1 infection. Methods Separation of CD8+ T cells from peripheral blood mononuclear cells (PBMCs) was carried out by using immunomagnetic beads coated with anti-CD8 antibody. Total RNAs from the purified CD8+ T lymphocytes were isolated and used to perform polymerase chain reaction (PCR) amplifications in CDR3 of 22 T cell receptor (TCR) gene families. CDR3 diversity and its association with viral load in individuals with HIV-1 infection were analyzed. Results An average diversity for all CDR3 profiles in CD8+ T cells from 9 HIV-infected individuals was significantly different as compared to 7 age-matched healthy donors (P<0.05) with the HIV-infected individuals losing diversity in the CDR3 profiles. There was positive correlation between changes in TCR CDR3 diversity and viral load (r=0.771,P<0.05). The changes in CDR3 length diversity of Vβ families in HIV-infected individuals, particular in Vβ2, Vβ4, Vβ5, Vβ17, Vβ20, Vβ21, Vβ23, Vβ24, were statistically different from the healthy controls. Conclusion HIV-1 infection might induce the loss of TCR Vβ repertoire diversity and disrupt the CDR3 distributions within CD8+ T cells. There should be positive correlation between changes in TGR CDR3 diversity and the viral load in HIV-1 infected patients.%目的 研究HIV-1感染者CD8+T细胞受体(TCR)基因的多样性变化特征及其与病毒载量的相关性.方法 应用抗CD8单克隆抗体从9份HIV-1感染者和7份HIV-1阴性对照样本外周血单个核细胞中分离CD8+T细胞,提取总RNA,然后采用一步(one step)及巢式(nested)多聚酶链式反应(PCR)的方法对22个T细胞受体Vβ基因家族的瓦补决定区3(CDR3)进行扩增,利用ABI-3700测序仪对扩增的PCR产物进行扣描,定量分析HIV-1感染者TCR CDR3区多样性变化特征及其与病毒载量的相关性.结果 HIV-1感染者和正常人相比较其CD8+T细胞的TCR基因多样性明显减少,部分TCR Vβ基因家族CDR3区的高斯分布破坏;TCR的紊乱与病毒载量呈正相关(r=0.771,P<0.05);HIV-1感染引起患者TCR多样性的改变不仅表现在不同Vβ基因家族上,而且也表现在CDR3长度上,其中感染者VB2、Vβ4、Vβ5、Vβ17、Vβ20、Vβ21、Vβ23及Vβ24基因家族的变化与正常人存在统计学差异.结论 HIV-1感染能引起CD8+T细胞TCR基因多样性的减少及高斯分布的破坏,TCR CDR3区的紊乱与病毒载量呈正相关.