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

To study the effects of Porphyromonas gingivalis (P. g) infection with Ⅰ, Ⅱ and Ⅳ fimA genotypes on the expression of IL-1beta, IL-6 and TNF-alpha in human umbilical vein endothelial cells (HUVECs).

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.

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 2th 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).

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.