IL-24对非小细胞肺癌患者CD8^(+)T细胞体外功能的影响

In vitro influence of IL-24 on functions of CD8^(+)T cells from patients with non-small cell lung cancer

目的观察IL-24在体外对非小细胞肺癌(non-small cell lung cancer,NSCLC)患者CD8^(+)T细胞功能的影响。方法本研究入组28例NSCLC患者和17例健康对照者,收集外周血单个核细胞(peripheral blood mononuclear cells,PBMC)和支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF),分选CD8^(+)T细胞,反转录实时定量PCR检测CD8^(+)T细胞中IL-24受体(IL-20R1、IL-20R2和IL-22R1)mRNA的相对表达量。不同浓度重组人IL-24(10 ng/ml和100 ng/ml)刺激纯化CD8^(+)T细胞后,流式细胞术检测穿孔素和颗粒酶B的表达变化。建立CD8^(+)T细胞和NSCLC细胞系NCI-H1882细胞的直接接触和间接接触体外共培养系统,观察IL-24刺激后CD8^(+)T细胞诱导靶细胞死亡比例,以及IFN-γ和TNF-α的表达变化。组间比较采用t检验或LSD-t检验。结果CD8^(+)T细胞中未检测到IL-22R1 mRNA表达,CD8^(+)T细胞中IL-20R1和IL-20R2 mRNA相对表达量在健康对照者和NSCLC患者之间以及在非肿瘤部位和肿瘤部位之间的差异均无统计学意义(P>0.05)。NSCLC患者外周血和肿瘤部位CD8^(+)T细胞中穿孔素和颗粒酶B水平显著低于健康对照者和非肿瘤部位(P<0.05),低浓度IL-24(10 ng/ml)刺激不影响CD8^(+)T细胞中穿孔素和颗粒酶B水平(P>0.05),而高浓度IL-24(100 ng/ml)则显著提升NSCLC患者CD8^(+)T细胞中穿孔素和颗粒酶B水平(P<0.05)。直接接触共培养系统中,高浓度IL-24(100 ng/ml)刺激NSCLC患者肿瘤部位CD8^(+)T细胞后可诱导靶细胞死亡比例升高,以及IFN-γ和TNF-α表达升高,而低浓度IL-24(10 ng/ml)刺激对CD8^(+)T细胞诱导的靶细胞死亡和细胞因子分泌无显著影响。间接接触共培养系统中,IL-24刺激对CD8^(+)T细胞诱导的靶细胞死亡和细胞因子分泌均无显著影响。结论高浓度IL-24在体外可增强NSCLC患者CD8^(+)T细胞的直接细胞杀伤功能,但在体内IL-24可能并不影响CD8^(+)T细胞的功能。

Objective To investigate the in vitro influence of IL-24 on the functions of CD8^(+)T cells from patients with non-small cell lung cancer(NSCLC).Methods Twenty-eight NSCLC patients and 17 healthy individuals were enrolled in this study.Peripheral blood mononuclear cells(PBMC)and bronchoalveolar lavage fluid(BALF)were collected to isolate CD8^(+)T cells.Real-time reverse transcription-PCR was used to detect the expression of IL-24 receptors(IL-20R1,IL-20R2 and IL-22R1)at mRNA level in CD8^(+)T cells.Changes in the expression of perforin and granzyme B were measured by flow cytometry after stimulating purified CD8^(+)T cells with different concentrations of recombinant human IL-24(10 ng/ml and 100 ng/ml).In vitro direct and indirect contact co-culture systems were established for CD8^(+)T cells and NSCLC cell line(NCI-H1882 cells).CD8^(+)T cells induced target cell death and expression of IFN-γand TNF-αin response to IL-24 stimulation were analyzed.Student′s t test or LSD-t test was used for intergroup comparison.Results The expression of IL-22R1 at mRNA level was not detected in CD8^(+)T cells.No significant difference in IL-20R1 or IL-20R2 expression at mRNA level in CD8^(+)T cells was observed between healthy individuals and NSCLC patients,or between non-tumor sites and tumor sites(P>0.05).Perforin and granzyme B expression was significantly reduced in CD8^(+)T cells from peripheral bloods and tumor sites of NSCLC patients as compared with those from healthy individuals and non-tumor sites(all P<0.05).Low concentration of IL-24(10 ng/ml)did not affect perforin or granzyme B expression in CD8^(+)T cells(P>0.05),but high concentration of IL-24(100 ng/ml)significantly enhanced the expression of perforin and granzyme B in CD8^(+)T cells from NSCLC patients(P<0.05).In the direct contact co-culture system,increased ratio of dead target cells and up-regulated IFN-γand TNF-αexpression were induced after stimulating CD8^(+)T cells from tumor sites in NSCLC patients with high concentration of IL-24(100 ng/ml),but low concentration of IL-24(10ng/ml)had no significant influence on CD8^(+)T cell-induced target cell death and cytokine production.In the indirect contact co-culture system,neither target cell death nor cytokine production induced by CD8^(+)T cells was affected by IL-24 stimulation.Conclusions High concentration of IL-24 promoted the in vitro cytolytic function of CD8^(+)T cells from NSCLC patients,but might not influence the in vivo functions of CD8^(+)T cells.