不同fimA基因型牙龈卟啉单胞菌感染对人脐静脉内皮细胞分泌IL-1B、IL-6、TNF-α的影响

Effects of Porphyromonas gingivalis infection with different fimA genotypes on the secretion of IL-1B,IL-6,and TNF-α by human umbilical vein endothelial cells

目的研究Ⅰ、Ⅱ和Ⅳ fimA基因型牙龈卟啉单胞菌(Porphyromonas gingivalis,P. g)感染对人脐静脉内皮细胞(Human umbilical vein endothelial cells,HUVEC)IL-1β、IL-6和TNF-α表达的影响。方法根据不同fimA基因型感染HUVEC细胞分为Ⅰ fimA型刺激组、Ⅱ fimA型刺激组和Ⅳ fimA型组刺激组,同时设立阳性对照组(E.coli-LPS刺激)和阴性对照组(仅加入细胞培养液)。MTT检测细胞增殖,流式细胞术检测细胞凋亡,ELISA检测不同fimA基因型P. g刺激HUVEC细胞2 h、6 h和24 h后细胞培养上清液中IL-1β,IL-6和TNF-α含量。结果Ⅰ fimA型刺激组、Ⅱ fimA型刺激组和LPS组刺激24 h后,其细胞增殖与阴性对照组相比均受到抑制(P <0.05)。而各组细胞凋亡率差异无统计学意义。不同fimA基因型P. g刺激HUVEC细胞后,2 h后细胞培养上清液中IL-1β含量均高于刺激6 h和24 h;2 h、6 h后培养上清液中IL-6含量均低于刺激24 h后培养上清液IL-6含量;而细胞培养上清液中同一fimA型刺激组各时间TNF-α含量差异无统计学意义。Ⅱ fimA型和Ⅳ fimA型P. g对IL-1β、IL-6和TNF-α的诱导能力高于Ⅰ fimA型P. g(P<0.05)。结论不同fimA基因型P. g刺激HUVEC细胞致其功能紊乱的作用存在差异;Ⅱ fimA型和Ⅳ fimA型P. g具有较强的上调IL-1β,IL-6和TNF-α分泌的能力。

Objective To study the effects of Porphyromonas gingivalis(P. g) infection with Ⅰ,Ⅱ and Ⅳ fimA genotypes on the expression of IL-1 beta, IL-6 and TNF-alpha in human umbilical vein endothelial cells(HUVECs). Methods HUVECs infected with different fimA genotypes were divided into the fimA type Ⅰ stimulation group, fimA type Ⅱ stimulation group, fimA type Ⅳ stimulation group. In addition, a positive control group(E. coli LPS stimulation) and negative control group(cell culture medium only) were included. Cell proliferation was detected by MTT assay, and cell apoptosis was detected by flow cytometry. IL-1β, IL-6, TNF-α levels in the supernatant of HUVECs after P. g stimulation were assessed by ELISA at 2 h, 6 h and 24 h. Results HUVECs were infected by P. g with fimA type Ⅰ,fimA type Ⅱ and LPS for 24 h. Cell proliferation was inhibited compared with the negative control group(P < 0.05), but there was no significant difference in the apoptosis rate between P. g infection and the negative control group. IL-1β levels in cell culture supernatants were higher at 2 th than 6 and 24 h after stimulation of HUVECs with different fimA genotypes,while the IL-6 levels were higher at 24 h than the other time, while the TNF-α levels were no significant difference at every time. After fimA type Ⅱ and Ⅳ P. g infection, IL-1β, IL-6, and TNF-α levels were increased compared with fimA type Ⅰ P. g(P < 0.05). Conclusion Different P. g fimA genotypes have different effects on stimulating HUVECs to induce dysfunction. Here, fimA type Ⅱ and Ⅳ P. g exhibit a strong ability to upregulate the secretion of IL-1β, IL-6 and TNF-alpha.