滤泡辅助性T细胞及其相关因子在HIV疾病进展中的变化研究

Changes in follicular helper T （ Tfh ） cells and Tfh-related molecules during HIV-1 infection

目的通过对不同疾病进展阶段的HIV感染者外周血滤泡辅助性T细胞（follicular helper T cell, Tfh）进行分析，探讨Tfh及其相关因子对HIV感染疾病进程的影响，为进一步研究Tfh在HIV抗病毒治疗和疫苗研究提供科学依据。方法本研究招募HIV-1感染者33例，根据疾病进展情况分为HIV-1长期不进展者（long-term nonprogressors, LTNP）11例、快速进展者（rapid progressors, RP）10例、HIV典型进展者（typical progressors, TP）12例，同时招募11名健康人（normal control, NC）作为对照。分离受试者外周血单个核细胞，用多色流式的方法检测CD4＋CD45RA－CXCR5＋Tfh和CD4＋CD45RA－CXCR3－CXCR5＋PD-1＋Tfh及其表达ICOS、IFN-γ、IL-21因子的水平。此外，对血浆IL-10和CD19＋B细胞频数也进行分析，探讨Tfh与CD4、B细胞的关系。结果两个Tfh亚群比例在HIV-1感染人群均比正常对照高，CD4＋CD45RA－CXCR5＋Tfh在LTNP人群最高，与正常对照比较差异有统计学意义（P〈0.05）。Tfh相关因子ICOS、IFN-γ、IL-21在T细胞刺激剂作用下均有明显升高，ICOS＋Tfh与HIV-1疾病进展呈负相关，与CD19＋B细胞呈正相关（r＝－0.49，P〈0.01；r＝0.60，P〈0.05）。血浆IL-10的浓度在HIV-1感染者中有明显升高，TP组最高，其次为RP组（TP组vs NC组，P〈0.01；RP组vs NC组，P〈0.05）。结论外周血Tfh及其相关因子的表达在HIV-1感染者与健康对照者间差异有统计学意义，特定亚群Tfh与HIV-1疾病进展和B细胞功能密切相关。

ObjectiveTo analyze the changes in follicular helper T （Tfh） cells during HIV-1 infection, to investigate the influences of Tfh cells and Tfh-related molecules on HIV-1 progression and to provide references for further research on using Tfh cells in highly active antiretroviral therapy （HAART） and vaccines.MethodsThis study enrolled 33 patients with HIV-1 infection, including 11 long-term nonprogressors （LTNP）, 10 rapid progressors （RP） and 12 typical progressors （TP）, and 11 healthy subjects （normal controls, NC）. Peripheral blood mononuclear cells were isolated from each subject. Multicolor flow cytometry was performed to detect CD4＋ CD45RA-CXCR5＋ Tfh and CD4＋ CD45RA-CXCR3-CXCR5＋ PD-1＋ Tfh subsets and the levels of inducible costimulatory molecule （ICOS）, IFN-γ and IL-21. Moreover, the levels of IL-10 and the percentages of CD19＋ B cells in plasma samples of each group were also analyzed. Relationships among Tfh, CD4 and B cells were analyzed.ResultsThe percentages of both Tfh subsets were higher in patients with HIV-1 infection than in NC. Compared with NC, LTNP had the highest percentage of CD4＋ CD45RA-CXCR3-CXCR5＋ PD-1＋ Tfh cells （P〈0.05）. Expression of Tfh-related molecules ICOS, IFN-γ and IL-21 were enhanced significantly upon Staphylococcus enterotoxin B （SEB） stimulation, ICOS＋ Tfh cells were negatively related with HIV-1 progression, but had a positive correlation with CD19＋ B cells （r=-0.49, P〈0.01; r=0.60, P〈0.05）. IL-10 level in plasma increased significantly in patients with HIV-1 infection, especially in TP and RP （TP vs NC： P〈0.01; RP vs NC： P〈0.05）.ConclusionHIV-1 patients and NC had significant differences in the expression of Tfh cells and Tfh-related molecules in peripheral blood. ICOS＋ Tfh cells were closely related to the progression of HIV-1 infection and the function of B cells.