OBJECTIVETo investigate the effect of Porphyromonas gingivalis (Pg) with different fimA genotypes on vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) production by human umbilical vein endothelial cells (HUVEC).

METHODSIn the present study, PgATCC33277 (type I fimA genotype), WCSP 115 (type II fimA genotype), W83 (type IV fimA genotype), and Escherichia coli-lipopolysaccharide (Ec-LPS) were designed as experimental group 1, 2, 3, and positive control group, respectively, to stimulate HUVEC, and the un-stimulated HUVEC were analyzed as negative control group. The three strains of Pg were cultured anaerobically in standard condition, and then the Pg cells and Ec-LPS were co-cultured with HUVEC for 2, 6, and 24 h, respectively. The amount of ICAM-1 and VCAM-1 produced by HUVEC was detected with flow cytometry (FCM). The expression of ICAM-1 and VCAM-1 by HUVEC were assayed with confocal laser scanning microscope (CLSM).

RESULTSThe expression of ICAM-1 on the surface of HUVEC were intensified after infected by Pg with I, II, and IV fimA genotypes (P < 0.05). The amounts of ICAM-1 were 60.27 ± 5.43, 80.81 ± 1.44, and 85.94 ± 2.56 for Pg with type I fimA genotype, 86.69 ± 8.81, 90.19 ± 0.00, and 96.18 ± 0.48 for Pg with type II fimA genotype, 59.66 ± 0.40, 85.79 ± 4.86, and 96.04 ± 2.07 for Pg with type IV fimA genotype at 2, 6 and 24 h after infection, respectively. The up-regulation effects caused by Pg with type II and IV fimA genotypes were stronger than those caused by Pg with type I fimA genotype at different time points except at 2 h (P < 0.05). Under the present experimental condition, infected by Pg with type I, II and IV fimA genotypes stimulated low expression of VCAM-1 by HUVEC, it showed no significant differences among all the groups (P > 0.05). Expression of ICAM-1 and VCAM-1 in Pg infected HUVEC were confirmed by CLSM. Infection of HUVEC with Pg resulted in more fluorescence staining of ICAM-1 and VCAM-1 compared with that in uninfected HUVEC cultures.

CONCLUSIONSThe virulence and pathogenicity of Pg is associated with its fimA genotypes, Pg with type II and IV fimA genes possess stronger ability to stimulate HUVEC to up-regulate the expression of cell adhesion molecules, which may lead to disorders in vascular endothelial function.