Antibody induced by porphyromonas gingivalis fima-pvxcp dna vaccine inhibit host cell invasion and enhance phagocytosis

Abstract

Porphyromonas gingivalis (P. gingivalis) is strongly correlated with periodontitis and systemic conditions such as aspiration pneumonia and cardiovascular disease. Vaccination against P. gingivalis will provide help to limit its pathogenicity. In order to investigate the function of antibody induced by DNA vaccine encoding P. gingivalis FimA fused with the immuno-enhancing molecule potato virus X coat protein (PVXCP), abilities of the induced antibody to inhibit host cell invasion and enhance phagocytosis were determined. Mice were vaccinated with the FimA-PVXCP fusion vaccine (pcDNA3.FimA-PVXCP) or FimA vaccine (pcDNA3.FimA). Antibody levels to FimA were measured by ELISA on day 14 after boosting. Both DNA vaccines induced anti-FimA antibody production at the comparable levels. Number of P. gingivalis invading into Caco-2 cells was significantly lowered when the bacteria were pre-incubated with serum from mice vaccinated with pcDNA3.FimA-PVXCP, comparing to the group that bacteria was not pre-incubated with serum or pre-incubated with normal mouse serum. In addition, when P. gingivalis was pre-incubated with serum from pcDNA3.FimA-PVXCP vaccinated mice, phagocytic index was significantly higher than the group that bacteria was not pre-incubated with serum or pre-incubated with normal mouse serum or serum from pcDNA3.FimA vaccinated mice. Therefore, anti-FimA antibody induced by FimA-PVXCP DNA vaccine could inhibit P. gingivalis cell invasion and also enhance phagocytosis.