TGF-β1 对γδT 细胞TLR-4 受体及IL-2、IFN-γ 水平的影响

TGF-β1 down-regulates expression of TLR-4 and reduces secretion of IL-2 and IFN-γ in γδT cells

摘要:

目的 探讨转化生长因子β1（TGF-β1）对γδT 淋巴细胞Toll 样受体4（TLR-4）蛋白表达 的影响，及TGF-β1 对γδT 淋巴细胞分泌淋巴因子白细胞介素2（IL-2）、干扰素γ（IFN-γ）的影响。 方法 从健康志愿者外周血中分离纯化γδT 淋巴细胞，并用外源性TGF-β1、脂多糖（LPS）刺激γδT 淋巴细胞，分为4 组培养：空白对照组、LPS 组、LPS+TGF-β1 组、TGF-β1 组。培养12 d 后采用酶联免疫 吸附法检测淋巴因子IFN-γ、IL-2 的表达，Western blot 检测TLR-4 蛋白的表达，PCR 检测TLR -4 基因的 转录。结果 与空白对照组相比，LPS 组、LPS+TGF-β1 组TLR-4 蛋白的转录及表达水平升高（P <0.05）， 淋巴因子IL-12 和IFN-γ 的表达增加；TGF-β1 组TLR-4 蛋白的表达、转录及IL-2 的表达降低（P <0.05）。 与LPS 组相比，LPS+TGF-β1 组TLR-4 蛋白的转录及表达、淋巴因子IL-12 和IFN-γ 的表达降低（P <0.05）。 结论 TGF-β1 能抑制γδT 淋巴细胞TLR-4 蛋白的表达，降低γδT 淋巴细胞分泌IFN-γ、IL-2 淋巴 因子的水平。

Abstract:

Objective To research the influence of exogenous TGF-β1 on the expression of TLR-4 and inflammatory cytokines (IL-2 and IFN-γ) in the γδT cells. Methods Peripheral γδT cells were collected from healthy human blood, the exogenous TGF-β1 and LPS were co-cultured with γδT cells which were divided into four groups including blank control group, LPS group, LPS+TGF-β1 group and TGF-β1 group. After 12 days the expressions of TLR-4 were detected by PCR and Western blot, the expression levels of IL-2 and IFN-γ were determined by ELISA. Results Compared with the blank control group, the expressions of TLR-4 and the levels of IL-2 and IFN-γ were markedly higher in the LPS and LPS+TGF-β1 groups (P < 0.05), but the expressions of TLR-4 and IL-2 were lower in the TGF-β1 group (P < 0.05). Compared with the LPS group, the expressions of TLR-4 and the levels of IL-2 and IFN-γ were significantly lower in the LPS+TGF-β1 group (P < 0.05). Conclusions TGF-β1 can down-regulate the expression of TLR-4 protein and reduce the secretion of IL-2 and IFN-γ in γδT cells.