蛋氨酸脑啡肽调控骨髓巨噬细胞前体分化信号通路的研究

Signal Transduction Mechanism of Macrophages Polarization Induced by Methionine Enkephalin

目的通过骨髓细胞的体外诱导实验,揭示蛋氨酸脑啡肽(MENK)对骨髓巨噬细胞前体分化的信号转导调控作用,探讨蛋氨酸脑啡肽调控巨噬细胞分化抗肿瘤的作用机制。方法应用流式细胞分析技术定量分析骨髓来源巨噬细胞细胞膜特异性标志物(F4/80)及功能表型CD64、CD206分子的表达;应用蛋白免疫印迹(Western-blotting)技术定量分析骨髓巨噬细胞前体信号转导通路相关蛋白NF-kB及STAT6的表达。结果 MENK(10-12mol·L-1)可明显上调骨髓来源巨噬细胞CD64分子的表达,下调CD206的表达。MENK处理组CD64的表达明显高于RPMI 1640组(P<0.01),但与MENK+LPS+IFN-γ处理组及LPS+IFN-γ处理组比较无显著差异(P>0.05),而MENK+IL-4处理组较IL-4处理组显著升高(P<0.01)。与IL-4处理组比较,MENK+IL-4处理组CD206的表达明显下调(P<0.01)。MENK可明显上调骨髓巨噬细胞前体NF-κB的表达,与未加MENK刺激组比较有显著差异(P<0.01),同时MENK可显著下调由IL-4介导的STAT6的表达(P<0.05)。结论本实验结果表明,MENK可通过抑制由IL-4介导的STAT6信号通路的激活,有效上调NF-κB的表达,有利于M1型细胞因子和NF-kB位点的结合,从而有效调控巨噬细胞由M2型向M1型转化。

OBJECTIVE To investigate the signal transduction mechanism of macrophages polarization induced by methionine en- kephalin（ MENK）, which can promote tumoricidal responses in vitro. METHODS The phenotype of macrophages were assessed by the quantitative analysis of key surface molecules on macrophages with flow cytometry （CI）64, CD206）. The expressions of NF-kB/ STAT6 signal transduction were analyzed with Western-blotting. RESULTS MENK（ 10-12mool·L-1 ） could significantly decrease the expression of CD206（P 〈 0. 01 ）, and at the same time, it could increase the expression of CD64 significantly（P 〈 0. 01 ）. MENK could increase the expression of NF-KB compared with MENK-untreated group. Furthermore MENK could inhibit the activation of STAT6 which is mediated by IL-4 （ P 〈 0.05 ）. CONCLUSION MENK could inhibit the activation of STAT6 signaling pathway medi- ated by IL-4. Meanwhile, MENK could increase the expression of NF-KB and be conducive to the combination of NF-kB sites with M1- type cytokines, consequently MENK could induced the conversion of macrophages from M2 to M1 phenotype effectively.