可溶性Tim-3体外增强免疫应答的作用及机制研究

Promotion of immune response by soluble Tim-3 in vitro and therapeutic potential

目的评价重组人(hTim-3)-Fc融合蛋白在调节免疫应答中的作用及其机制研究。方法分别将重组hTim-3-Fc融合蛋白与人巨噬细胞系U937细胞、T淋巴细胞系Jurkat细胞及正常人外周血细胞共培养,采用ELISA、实时荧光定量PCR(RT-PCR)和蛋白质免疫印迹(Western印迹)方法检测免疫相关细胞因子水平的变化,探讨重组hTim-3-Fc融合蛋白对免疫细胞活性的影响并阐明机制。结果重组hTim-3-Fc融合蛋白可显著提高免疫细胞活性,表现为U937中IL-8分泌水平,Jurkat细胞IL-2分泌水平,以及人外周血中IL-2和IFN-γ分泌水平显著升高;在mRNA水平,发现重组hTim-3-Fc融合蛋白能显著提高上述细胞中Ⅰ型干扰素(包括IFN-α2、IFN-β1)的表达。在分子机制方面,重组hTim-3-Fc融合蛋白可增强T细胞(Jurkat)及巨噬细胞(U937)中stat-1的磷酸化水平。结论制备的重组人Tim-3-Fc融合蛋白在体外能显著增强免疫细胞活性,有望成为免疫抑制性疾病新的免疫干预药物。

Objective To evaluate the role of recombinant human soluble Tim-3（hTim-3-Fc） in regulating immune response. Methods Soluble hTim-3 was incubated with human macrophage cell line U937,human T cell line Jurkat and normal human PBMC before cytokines secreted by or expressed in different immune cells were analyzed using ELISA,RT-PCR and Western-blotting,respectively. Results Soluble hTim-3 significantly promoted the activation of different immune cells. Our data showed that IL-8 secretion by U937 cells,IL-2 secretion by Jurkat cells,IL-2 and IFN-γ secretion by human PBMCs were all significantly increased. In addition,soluble hTim-3 significantly increased the IFN-α2 and IFN-β1 mRNA expression in U937,Jurkat and PBMCs and increased the phosphorylation of stat-1 in Jurkat and U937 cells. Conclusion Recombinant soluble hTim-3 can significantly promote the activation of immune cells in vitro,which shows its therapeutic potential.