抑制Toll样受体4表达对巨噬细胞极性转化的影响

Role of Toll-like receptor 4 expression inhibition in the transformation of macrophage polarity

目的通过观察CLI-095对巨噬细胞表型的影响,探讨Toll样受体4(TLR4)在巨噬细胞极性转化中的作用。方法以体外培养的小鼠骨髓来源巨噬细胞为研究对象,按数字表法随机分为3组,对照组(常规培养小鼠源性骨髓巨噬细胞48 h,不给予任何药物处理)、模型组(常规培养细胞24 h,换液后加入终浓度为1.0×105U/L的γ干扰素和5 mg/L脂多糖干预24 h)、处理组(先给予1 mg/L的CLI-095孵育细胞24 h,换液后加入终浓度为1.0×105U/L的γ干扰素和5 mg/L脂多糖干预24 h)。应用实时荧光定量聚合酶链反应检测TLR4 mRNA的表达;应用流式细胞术检测膜分子CD16/32、CD206的表达;用酶联免疫吸附法检测白细胞介素-10(IL-10)和IL-12的分泌。结果模型组较对照组CD16/32、IL-12明显升高,CD206明显降低,符合M1型巨噬细胞特性。处理组与模型组比较,TLR4 mRNA表达降低,提示TLR4受到抑制,CD16/32和IL-12表达下降,CD206和IL-10明显上升,差异有统计学意义(P<0.05),符合M2型巨噬细胞极性特点。结论 TLR4在巨噬细胞极性转化中起着重要的作用,抑制TLR4表达可诱导炎症性巨噬细胞向抗炎性M2型转化。

Objective To explore the role of Toll-like receptor 4 in the transformation of the bone marrow-derlved macrophage polarity through observation on the effects of CLI-095 on phenotype of macrophages. Methods Our research subjects were the cultured mouse marrow-derived macrophages, and were randomly divided into three groups： the control group （marrow-derived macrophages cultured for 48 h without any drug treatment）, the model group （ marrow-derived macrophages cultured routine for 24 h, then, addition of 100 U/ml 3/interferon and 5 ng/ml lipopolysaccharide into the culture medium and cultured for another 24 h） and the treatment group（first incubated in 1 μg/ml CLI-095 for 24 h, then, after change of the fluid, addition of 100 U/ml γ interferon and 5 ng/ml lipopolysaccharide into the culture medium and cultured for another 24 h）. Real-time quantitative PCR was used to detect the mRNA expression of TLR4. The expression of membrane molecules CD16/32, CD206 was detected by using fluorescence activated cell sorting （FACS）, and enzyme linked immunosorbent assay （ELISA） was used to detect the secretion of interleukin-10 （IL-10） and IL-12. Results As compared with those of the control group, the expression levels of CD16/32 and IL-12 in the model group were increased significantly, and the level of CD206 was decreased markedly, which was in conformity with the features of macrophages. When compared with those of the model group, the level of TLR4 mRNA was decreased. This indicated that the expression level of TLR4 was inhibited, the levels of CD16/32 and IL-12 were decreased and the levels of CD206 and IL-10 were increased with statistical significance and they were also in conformity with the features of macrophages. Conclusion TLR4 seemed to play an important role in the modulation of macrophage polarity. The inhibited expression level of TLR4 could promote inflammatory macrophages towards an anti-inflammatory M2 phenotype.