胸腺肽α1对THP-1细胞Toll样受体2和MyD88以及TNF-α表达的影响

Effects of Thymosin α1 on the expression of Toll-like receptor 2, MyD88 and TNF-α in THP-1 cell line

目的:观察人THP-1细胞与胸腺肽α1(Tα1)孵育后,予细菌脂蛋白(BLP)刺激后,Toll样受体2(TLR2)、髓系分化因子88(MyD88)蛋白的表达及细胞因子TNF-α的变化。方法:实验采用人THP-1细胞系进行细胞培养,分为4组:对照组为THP-1细胞不加任何刺激;BLP组以1000ng/mlBLP刺激2h;Tα1组为THP-1细胞加1000ng/mlTα1孵育24h,不加BLP刺激;Tα1+BLP组为THP-1细胞加1000ng/mlTα1孵育24h后再加1000ng/mlBLP刺激2h。以Westernblot分析TLR2、MyD88蛋白含量。ELISA法测定TNF-α。结果:与对照组相比,BLP组和Tα1+BLP组的TNF-α均显著增加,而Tα1组无显著改变;在TLR2和MyD88的表达上,Tα1组和Tα1+BLP组均高于对照组和BLP组。结论:胸腺肽α1可增加THP-1细胞TLR2、MyD88蛋白的表达,其对免疫细胞的影响与BLP诱发炎症反应的途径不完全一致。

Objective： To study the effects of thymosin α1 on the expression of Toll-like receptor 2 （TLR2）, myeloid differentiation factor 88（MyD88） and TNF-α in human THP-1 cell line stimulated by bacterial lipoprotein（BLP） with different ways. Methods： Human THP-1 cells were incubated and divided into 4 groups：control group （incubated in RPMI-1 640 cell cuhure fluid with no stimulus）, BLP group （stimulated with 1 000 ng/ml of BLP for 2 h）, Tα1 group （incubated with 1 000 ng/ml thymosin α1 for 24 h）, and Tctl＋ BLP group （stimulated with 1 000 ng/ml of BLP for 2 h after incubated with thymosin α1）. TLR2,MyD88 protein concentration were detected using western blot analysis, and TNF-α was detected using available ELISA kit. Results：The concentration of TNF-α in Tα1 group had no change compared to control group. It increased in BLP group and Tα1＋ BLP group ,while there was no difference between both groups. TLR2 and MyD88 protein expression in Tα1 group and Tα1＋ BLP group were up-regulated. Conclusion： Thymosin α1 up-regulates the expression of TLR2 and MyD88 protein in THP-1 cell line. The mechanisms for increase of TNF-α synthesis in THP-1 cells caused by Tα1 may be partly different from that induced by BLP.