中枢神经系统炎症对抗原递呈细胞白细胞介素-27表达影响

Regulation of interleukin-27 in brain antigen-presenting cells by central nervous system inflammation

摘要:

目的：探讨在炎症因子与凋亡细胞刺激下对中枢神经系统抗原递呈细胞白细胞介素（interleukin，IL）-27的表达调控。方法：用脂多糖（lipo-polysaccharide，LPS）、干扰素-γ（interferon-γ，IFN-γ）和X射线诱导凋亡细胞对小鼠小胶质细胞和骨髓源树突状细胞刺激。采用实时定量 PCR法，检测不同刺激组小胶质细胞和树突状细胞 p28基因mRNA的转录水平。Western blot法检测不同刺激组细胞 IL-27蛋白表达水平。结果：LPS刺激和 LPS与 IFN-γ共刺激的小胶质细胞和树突状细胞 p28 mRNA表达与空白组相比明显升高（小胶质细胞：PLPS 0.50 μg/ml=0.029；PLPS+IFN-γ=4×10-7；树突状细胞：P0.50 μg/ml=0.021；PLPS+IFN-γ=8×10-7），凋亡细胞预刺激组p28基因 mRNA转录水平明显低于LPS和IFN-γ刺激组，差异有统计学意义（小胶质细胞：PLPS+凋亡细胞=1.2×10-4；PIFN-γ+LPS+凋亡细胞=1×10-7；树突状细胞：PLPS+凋亡细胞=3×10-4；PIFN-γ+LPS+凋亡细胞=2×10-7）。IL-27蛋白表达水平在 LPS和 IFN-γ刺激组明显增加（小胶质细胞：PLPS 0.25 μg/ml=0.022； PLPS+IFN-γ=8×10-7；树突状细胞：PLPS 0.50 μg/ml=0.021；PLPS+IFN-γ=2×10-7），在凋亡细胞预刺激组表达下降（小胶质细胞：PLPS+凋亡细胞=9.6×10-5；PIFN-γ+LPS+凋亡细胞=3×10-7；树突状细胞：PLPS+凋亡细胞=0.001；PIFN-γ+LPS+凋亡细胞=1.1×10-5）。结论：中枢抗原递呈细胞在 LPS和 IFN-γ刺激下 IL-27 p28 mRNA和IL-27蛋白表达增加，吞噬凋亡细胞后 IL-27 p28 mRNA和 IL-27蛋白表达下降。

Abstract:

Objective：To explore how inflammatory factors and apoptotic cells regulate central nervous system（CNS） antigen-present－ing cells（APCs） related cytokine-interleukin-27（IL-27） expression in inflammation. Methods：qRT-PCR was used to measure and compare IL-27 p28 mRNA relative expression in mice microglia cells and bone marrow derived dendritic cells（BMDCs），treated with lipopolysaccharide（LPS），interferon-γ（IFN-γ） and X-ray induced apoptotic cells. Western blot was performed to detect IL-27 ex－pression in different stimuli groups. Results：Expressions of IL-27 p28 mRNA and IL-27 were up-regulated when microglia cells and BMDCs being treated with LPS and increased expressions of IL-27 p28 and IL-27 were in relation with LPS dosages. Expressions of IL-27 p28 mRNA and IL-27 were significantly up-regulated when microglia cells and BMDCs being treated with IFN-γ plus LPS（microglia cells：PLPS 0.50 μg/ml=0.029，PLPS+IFN-γ=4×10-7；BMDCs：P0.50 μg/ml=0.021，PLPS+IFN-γ=8×10-7）. Expressions of IL-27 p28 mRNA and IL-27 were significantly down-regulated when microglia cells and BMDCs being pre-treated with apoptotic cells（microglia cells：PLPS+apoptotic cells=1.2×10-4，PIFN-γ+LPS+apoptotic cells=1×10-7；BMDCs：PLPS+apoptotic cells=3×10-4，PIFN-γ+LPS+apoptotic cells=2×10-7）. Conclusions：LPS and IFN-γ can up-regulate IL-27 expression in CNS APCs. IL-27 expression is suppressed when CNS APCs phagocytosis of apoptotic cells.