转化生长因子β1抑制T淋巴细胞功能及其相关机制的体外研究

发布时间：2018-01-17 17:34

本文关键词：转化生长因子β1抑制T淋巴细胞功能及其相关机制的体外研究　出处：《安徽医科大学》2005年硕士论文　论文类型：学位论文

【摘要】：目前治疗器官移植排斥反应的方法主要是应用各种免疫抑制剂以及抗CD3、CD4等免疫活性细胞和活性分子的单克隆抗体,临床效果较为满意,但存在严重的全身性免疫抑制,已诱发感染和肿瘤发生。因此诱导机体产生特异性免疫耐受是克服移植排斥的理想途径,始终是免疫学研究的热点。近年来,应用细胞因子及其单克隆抗体治疗器官移植排斥反应受到广泛的重视,其中以转化生长因子β(TGF-β)尤为引人关注。TGF-β是一种多向性的细胞因子,对免疫系统具有广泛的抑制作用,极微量就具有很强的免疫抑制作用。一系列动物体内和体外实验证实TGF-β可以抑制T淋巴细胞增殖,并诱导出免疫耐受,本实验试图通过观察TGF-β1对人外周血T淋巴细胞增殖的影响,对其可能的作用机制进行初步研究,以期为日后临床应用的可能性提供实验依据。目的通过TGF-β对T细胞的抗增殖作用及其可能机制的研究,试图为移植排斥反应的治疗提供一条新的途径。本实验观察TGF-β1在混合淋巴细胞反应中对T细胞增殖的影响,并进一步探讨其作用机理。方法分离不同个体健康成年人外周血淋巴细胞进行初次及再次混合淋巴细胞培养(MLC),设TGF-β1组和对照组,在不同时间点以MTT法检测T细胞增殖率,用乳酸脱氢酶法测定细胞毒活性,以ELISA法测定培养上清中IFN-γ及IL-2水平,并用流式细胞仪检测T细胞表面CD4CD25及CTLA4抗原表达。结果初次及再次MLC均显示,TGF-β1组细胞增殖反应明显低于对照组,CTL的细胞毒性受到明显抑制,初次MLC中TGF-β1组培养上清内IFN-γ及IL-2水平明显低于对照组。初次MLC 5天后反应体系中CD4CD25T细胞比例及CTLA4抗原表达明显高于对照组。在再次MLC中,TGF-β1作用过的反应细胞对来自第三者的刺激细胞无反应。结论 ① TGF-β1在人外周血混合淋巴细胞培养中对T细胞增殖有显著抑
[Abstract]:At present, the main treatment for organ transplantation rejection is to use a variety of immunosuppressants and monoclonal antibodies against immunoreactive cells and active molecules such as CD3P4. The clinical results are satisfactory. But there is serious systemic immunosuppression, which has induced infection and tumorigenesis. Therefore, inducing specific immune tolerance is an ideal way to overcome transplant rejection and has always been a hot topic in immunology. The application of cytokines and their monoclonal antibodies in the treatment of organ transplantation rejection has received extensive attention. Transforming growth factor 尾 (TGF- 尾) is a multidirectional cytokine, which has a wide range of inhibitory effects on the immune system. A series of animal experiments in vivo and in vitro confirmed that TGF- 尾 could inhibit the proliferation of T lymphocytes and induce immune tolerance. By observing the effect of TGF- 尾 1 on the proliferation of human peripheral blood T lymphocytes, the possible mechanism of TGF- 尾 1 was studied in order to provide experimental evidence for the possibility of clinical application in the future. Objective to study the antiproliferative effect of TGF- 尾 on T cells and its possible mechanism. In this study, we observed the effect of TGF- 尾 1 on the proliferation of T cells in mixed lymphocyte reaction, and further discussed the mechanism of TGF- 尾 1 on T cell proliferation. Methods Peripheral blood lymphocytes from healthy adults were isolated and cultured for the first time and again. TGF- 尾 1 group and control group were divided into two groups: TGF- 尾 1 group and control group. At different time points, T cell proliferation rate was detected by MTT method, cytotoxic activity was measured by lactate dehydrogenase assay, IFN- 纬 and IL-2 levels in culture supernatant were measured by ELISA method. The expression of CD4CD25 and CTLA4 on T cells was detected by flow cytometry. Results MLC showed that the cytotoxicity of TGF- 尾 1 group was significantly lower than that of control group. The levels of IFN- 纬 and IL-2 in the culture supernatant of the primary MLC group were significantly lower than those in the control group. After 5 days, the proportion of CD4CD25T cells and the expression of CTLA4 antigen in the reaction system were significantly higher than those in the control group. TGF- 尾 _ 1-尾 _ (1)-activated response cells did not respond to stimulation cells from third parties. Conclusion 1 TGF- 尾 1 has a significant inhibitory effect on T cell proliferation in human peripheral blood mixed lymphocyte culture.
【学位授予单位】：安徽医科大学
【学位级别】：硕士
【学位授予年份】：2005
【分类号】：R392.4

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