梅毒螺旋体膜蛋白 Tpp17体外活化血管内皮细胞的实验研究

Treponema pallidum membrane protein Tpp17 activates vascular endothelial cells in vitro

目的：研究梅毒螺旋体重组蛋白Tpp17体外对人脐静脉内皮细胞（ HUVEC ）的活化作用，探讨膜蛋白Tpp17在梅毒免疫学发病机制中的作用。方法将采用基因工程技术重组合成的梅毒螺旋体膜蛋白Tpp17刺激HUVEC， ELISA测培养上清中细胞因子TNF-α、MCP-1、ICAM-1及E-selectin的水平，荧光定量聚合酶链反应测HUVEC中TNF-α、MCP-1、ICAM-1及E-selectin mRNA的转录水平；将重组蛋白Tpp17预处理的HUVEC与Calcein-AM标记的THP-1细胞共培养，荧光倒置显微镜下观察HUVEC与THP-1细胞的黏附情况；将HUVEC接种于transwell小室的下室，重组蛋白Tpp17处理后，Calcein-AM标记的THP-1细胞接种于上室，荧光倒置显微镜观察下并计数THP-1细胞的迁移率。结果梅毒螺旋体膜重组蛋白Tpp17可上调HUVEC细胞因子TNF-α、MCP-1、ICAM-1及E-se-lectin的表达水平，提高其对THP-1细胞的趋化和黏附能力，与空白组比较，差异有统计学意义（ P＜0．05）。结论梅毒螺旋体膜重组蛋白Tpp17可体外活化HUVEC，提高HUVEC对THP-1细胞的趋化和黏附能力，可能在梅毒的免疫病理中起重要作用。

Objective To study the effects of Treponema pallidum membrane protein Tpp17 on ac-tivation of human umbilical vein endothelial cells （HUVECs） in vitro and to understand its role in the immu-nopathogenesis of syphilis .Methods HUVECs were co-cultured with recombinant protein Tpp 17.Then the expressions of TNF-α, MCP-1, ICAM-1 and E-selectin at mRNA and protein levels in supernatants were re-spectively detected by enzyme-linked immunosobent assay （ ELISA ） and fluorescent real-time quantitative PCR.The adhesive ability of THP-1 cells was observed by fluorescence microscopy after co-cultured pretrea-ted HUVECs with recombinant protein Tpp 17 with Calcein-AM labeled THP-1.Pretreated HUVECs were cultured in the lower chamber of Transwell with recombinant protein Tpp 17 and monocytic THP-1 cells were cultured in the upper chamber of Transwell .After that, the migration of monocytic THP-1 cells was evalua-ted by using fluorescence microscopy .Results Compared with the blank control group , the expression of TNF-α, ICAM-1, E-selectin, especially the MCP-1, were enhanced by recombinant protein Tpp 17 of Trepo-nema pallidum.Moreover, Tpp17 improved the adhesive ability and migration of monocytic THP-1 cells, es-pecially the latter.Conclusion Treponema pallidum membrane protein Tpp17 might play a certain role in the immunopathogenesis of syphilis by enhancing the expression of TNF-α, MCP-1, ICAM-1 and E-selectin, and by promoting the adherence ability and migration of monocytic THP-1 cells.