老年肺结核患者外周血CD4^+CD8^+T细胞表达水平及临床意义

The expression level and clinical significance of CD4^+CD8^+T cells in peripheral blood of elderly patients with pulmonary tuberculosis

目的探讨老年肺结核患者外周血CD4^+CD8^+T细胞的表达水平、免疫表型及抗结核能力,为评价抗结核治疗效果提供依据。方法选取本院2015年6~9月收治的112例老年肺结核患者纳入研究组,按照治疗情况将其分为初治组、复治组与治愈组。另选取同期于本院体检中心体检的80例健康志愿者纳入对照组。采用流式细胞仪检测入选研究对象外周血CD4^+CD8^+T细胞的表达水平,并分析其与肺结核发生发展的关系;检测分析CD4^+CD8^+T细胞免疫功能、活化标记及记忆表型,并分析CD4^+CD8^+T细胞的抗结核免疫应答能力。结果初治组患者外周血CD4^+CD8^+T细胞表达水平明显高于对照组和治愈组(P<0.05);随着治疗时间的延长,外周血CD4^+CD8^+T细胞表达水平逐渐下降;CD4^+CD8^+T细胞的免疫功能优于CD4^+T细胞与CD8^+T细胞;抗原肽刺激组患者外周血CD4^+CD8^+T细胞表达肿瘤坏死因子-α(TNF-α)与干扰素-γ(IFN-γ)的水平均高于无抗原肽刺激组(P<0.05)。结论结核分枝杆菌可刺激肺结核患者外周血CD4^+CD8^+T细胞的表达,分泌炎性细胞因子TNF-α与IFN-γ,参与抗结核免疫应答。CD4^+CD8^+T细胞表达水平变化在一定程度上可以反映抗结核治疗效果,监测外周血CD4^+CD8^+T细胞的表达水平可评估患者的预后。

Objective To investigate the expression of CD4^＋CD8^＋T cells in peripheral blood of elderly patients with pulmonary tuberculosis, and to provide a basis for the evaluation of the efficacy of anti tuberculosis treatment. Method 112 cases of elderly patients with pulmonary tuberculosis admitted to our hospital from June 2015 to September 2015 were enrolled in study group, according to the treatment, they were divided into initial treatment group, re-treatment group and cure group. 80 cases of healthy volunteers were enrolled in control group during the same period. The expression levels of peripheral blood CD4^＋CD8^＋T cells of all the research objects were detected by flow cytometry, the relationship between levels of CD4^＋CD8^＋T cells and occurrence and development of pulmonary tuberculosis were analyzed, immune function, activation markers and memory phenotype of CD4^＋CD8^＋T cells were detected, tuberculosis immune response ability of CD4^＋CD8^＋T cells were analyzed. Result The proportion of CD4^＋CD8^＋T cells in the initial treatment group was significantly higher than control group and cure group（P〈0.05）; with the prolongation of treatment time, the expression level of CD4^＋CD8^＋T cells decreased gradually. The immune function of CD4^＋CD8^＋T cells was better than that of CD4^＋T cells and CD8^＋T cells. The proportion of TNF-α and IFN-γ of CD4^＋CD8^＋T cells expressed in antigenic peptide stimulation group was higher than non-antigenic peptide stimulation group（P〈0.05）. Conclusion Mycobacterium tuberculosis can stimulate the expression of CD4^＋CD8^＋T cells in peripheral blood of patients with pulmonary tuberculosis, secrete inflammatory cytokines TNF-α and IFN-γ, and participate in anti-tuberculosis immune response. The proportion of CD4^＋CD8^＋T cell can reflect the efficacy of anti-tuberculosis treatment, therefore monitoring the expression level of CD4^＋CD8^＋T cells in peripheral blood can assess the prognosis of patients.