结核分枝杆菌P19对巨噬细胞TLR-2表达及分布的影响

Influence of Mycobacterium tuberculosis 19 kDa lipoprotein upon the expression and distribution of Toll-like receptor-2 on the surface of macrophages

目的探讨结核分枝杆菌19kD脂蛋白(Mtb P19)对单核巨噬细胞表面TLR-2表达的影响。方法以10μg/ml Mtb P19作用于拂波醇酯(PMA)分化的THP-1细胞,CO2孵箱孵育6 h。免疫细胞化学法(ICC)观察巨噬细胞TLR-2分布;对巨噬细胞TLR-2进行荧光抗体染色,流式细胞术分析P19作用前后TLR-2的表达变化;激光共聚焦显微镜观察其受体排列。结果ICC法观察发现TLR-2均匀分布于巨噬细胞表面。P19作用组与对照组相比平均荧光强度明显增强;在作用组细胞表面出现多个斑块状染色阳性的荧光标记区,而对照组TLR-2分子总体呈现随机动态的分布。结论Mtb P19不仅能诱导巨噬细胞TLR-2表达增加,还可以引起受体发生功能性聚集。

To observe the effect of Mycobacterium tuberculosis 19 kDa lipoprotein （Mtb P19） upon the expression and distribution of Toll like receptor-2 （TLR-2） on the surface of macrophages, Mtb P19 was prepared from the cultured M. tuberculosis H37 Ra strain , and phorbol myristatye acetate （PMA）-differentiated THP-1 cells were co-cultivated with Mtb P19 at concentration of 10 g/mL and at 37 ℃ temperature and a condition containing 5 % CO2. for 6 hours.. The distribution of TLP- 2 on the surface of macrophages was investigated by immuno-cellular chemical method （ICC） while the effect of Mtb P19 upon the expression of TLR on the surface of macrophages was assayed by fluorescent antibody staining. In addition, the changes of TLR-2 expression before and after the effect of Mtb P19 were investigated by flow cytometry analysis and change of TLR-2 arrangement after stimulation with Mth P19 was determined by co-focal microscopy. It was found that the TLR-2 molecules were evenly distributed on the surface of macrophages as demonstrated by ICC. The mean fluorescent intensity increased significantly after stimulation with Mtb P19 for 6 hours in comparison with that of the control group, and the patchy surface with fluorescent staining positive zones could be detected on the surface of macrophages. Nevertheless , the distribution of TLR 2 molecule in the control group appeared to he randomly dynamic. It is evident that the Mth P19 not only can induce the surface expression of TLR-2 molecules, but also cause a functional aggregation of this receptor.