共刺激分子CD28、CD137在喉癌患者T淋巴细胞中的表达及其与细胞免疫功能失调的关系

Expression of costimulatory molecules CD28 and CD137 on T-lymphocytes and their association with immune dysfunction in patients with laryngeal carcinoma

目的探讨共刺激分子CD28、CD137与喉癌患者细胞免疫功能状况的关系。方法应用梯度离心法分离并纯化外周血和肿瘤浸润淋巴细胞(tumor infiltrating lymphocyte,TIL),流式细胞术检测喉癌患者外周血T细胞CD8+、CD8+CD28+、CD8+CD28-、CD28+细胞亚群分布和双香豆素(phytohemagglutinin,PHA)刺激前后患者外周血T细胞及TIL中CD137的表达。结果喉癌患者CD8+T细胞比率为(32.11±5.07)%,CD8+CD28-T细胞比率为(21.03±5.69)%,均明显高于正常对照组(均P<0.01);CD28+T细胞比率为(45.53±4.51)%,CD8+CD28+T细胞比率为(12.70±3.41)%,均明显低于正常对照组(P均<0.01)。CD137+T细胞活化增殖能力与CD28的阳性表达呈明显的正相关,喉癌患者外周血T细胞和TIL在未受PHA刺激时CD137+T细胞比率分别为(1.90±0.71)%和(3.52±1.64)%,明显高于正常对照组(P均<0.01)。但经PHA刺激48小时后,外周血和TIL中CD137+-48h/CD137+-0h值为分11.48±4.03和10.39±3.02,均明显低于正常对照组,P均<0.01。结论共刺激分子CD28在CD8+T细胞亚群中的表达失调使免疫效应性CD137+T细胞活化增殖能力下降,是引起喉癌患者细胞免疫功能紊乱的重要原因之一。

OBJECTIVE To investigate the expression of costimulatory molecules CD28 and CD137 on T-lymphocytes and their association with immune dysfunction in patients with laryngeal carcinoma. METHODS The T lyphocytes were isolated and purified from peripheral blood cells （PBCs）and tissues of laryngeal carcinoma with density gradient centrifugation methods. The expression of CD8^＋, CD28^＋, CD8^＋CD28^＋, CD8^＋CD28^- and CD137^＋ on T-lymphocytes of PBCs and tumor infiltrating lymphocytes（TILs）were detected by direct immunofluorescent staining and flow cytometry. RESULTS The CD8^＋ T cells （32.11±5.07）% in PBCs of the patients with laryngeal carcinoma were significantly higher than those of normal subjects （27.01±3.66）%, P 〈0.01. Whereas the CD28^＋ T cells（45.53±4.51）% in PBCs of the patients with laryngeal carcinoma was significantly lower than those of the normal subjects （54.29±6.28）%, P 〈0.01. The CD8^＋ CD28^＋ T cells accounted for（12.70±3.41）% of PBCs in patients with laryngeal carcinomas, which was ...更多significantly lower than that in the normal persons （15.97±2.13）%, P 〈0.01. In contrast, the rate of the CD8^＋ CD28^-T cells was（21.03±5.69）% in PBCs of the patients with laryngeal carcinomas, which was significantly higher than that in the normal persons （11.31±2.99）%, P 〈0.01. Before stimulation with PHA, the rates of CD137^＋T cells in PBCs and TILs of patients with laryngeal carcinomas were（1.90 ±0.71）% and（3.52±1.64）% respectively, which were significantly higher than that in normal persons （0.79±0.40）%, P 〈0.01. The activation proliferation of CD137^＋ T cells was associated with expressions of CD8 and CD28. After stimulation by PHA, the potentials of activation proliferation of CD137^＋T cells which was represented by CD137^＋-48h/CD137^＋-0h ratios were 11.48±4.03 and 10.39±3.02 in PBCs and TILs in laryngeal carcinoma patients respectively, which were significantly lower than that in the normal persons （21.46±9.46, P 〈0.01）. CONCLUSION Disproportion of CD28 expression in CD8^＋ T cells could result in abrogation of activation proliferation of CD137^＋ T cells, which might be responsible for cellular immunity dysfunction in laryngeal carcinoma patients.