摘要目的 探讨结核分枝杆菌(MTB)?特异性多肽E7诱导单核?巨噬细胞向M2型分化的信号通路.方法 将相同个数的单核?巨噬细胞分为空白对照组、M1阳性组[用脂多糖及γ?干扰素(IFN?γ)共同刺激]、M2阳性组(用IL?4和IL?13共同刺激)和E7实验组(用MTB?特异性多肽E7刺激),分别于刺激后12、18、24和36 h检测细胞的M1型标志物CD16、IL?6、肿瘤坏死因子?α(TNF?α)和M2型标志物CD163、CD206、IL?10的表达水平;用过氧化物酶体增殖剂激活受体?γ(PPAR?γ)阻断剂分别处理空白对照组、M2阳性组和E7实验组24 h,检测各组在加入阻断剂前后PPAR?γ和CD163的表达情况,采用t检验对各组结果进行比较.结果 与阳性组和空白对照组比较,E7实验组在刺激巨噬细胞至18 h时, TNF?α的表达逐渐达到高峰(相对表达量为20.02),随后逐渐下降且伴随CD163表达逐渐升高,24 h时CD163的表达至高峰(相对表达量为2.44);在加入阻断剂后E7实验刺激组的细胞PPAR?γ表达的量较阻断前明显降低(阻断前为0.94±0.06,阻断后为0.69±0.09,P=0.028);CD163的表达水平较阻断前明显下降(阻断前为3.95±0.61,阻断后为2.87±0.20,P=0.047).结论 MTB?特异性多肽E7可诱导单核?巨噬细胞向M2型分化,与PPAR?γ涉及的非受体酪氨酸激酶信号转导子和转录激活子信号通路相关.

abstractsObjective To explore the signal pathway of M2?type polarization induced by Mycobacterium tuberculosis (MTB)?specific peptide E7. Methods Monocyte?macrophages were divided into blank control group, M1 positive stimulus group [co?stimulated with lipopolysaccharide and gamma interferon (IFN?γ)], M2 positive group(co?stimulated with IL?4 and IL?13), and E7 experimental group (with MTB?specificity polypeptide E7 stimulated). The expression of M1 type markers CD16, IL?6, TNF?α and M2 type markers CD163, CD206, IL?10 were detected at 12, 18, 24 and 36 h. Furthermore, peroxisome proliferators?activated receptors?γ (PPAR?γ) blocker was used in the blank control group, M2?positive stimulus group and E7 experimental stimulus group. T test was used to compare the expression of PPAR?γ and CD163before and after the addition of blockers. Results Compared with the positive control group and the blank control group, the expression of TNF?α in the E7 experimental group gradually reached the peak when macrophages were stimulated for 18 h(the relative expression was 20.02), and then the expression of TNF?α gradually decreased and the expression of CD163increased. The expression of CD163peaked at 24 h (the relative expression was 2.44). After adding the inhibitor, the expression of PPAR?γ in E7 stimulation group was lower than before blocking (before blocking 0.94±0.06,after blocking 0.69±0.09,P=0.028). CD163expression level was significantly lower than that before blocking (before blocking 3.95±0.61,after blocking 2.87±0.20, P=0.047). Conclusion The MTB?specific peptide E7 induced differentiation of macrophages into M2 type, a process that may be involving PPAR?γ in just another kinase?signal transducer and activator of transcription pathway.