Atopic Biomarker Changes after Exposure to Porphyromonas gingivalis Lipopolysaccharide: A Small Experimental Study in Wistar Rat

BackgroundIgE and IgG4 are implicated in atopic development and clinically utilized as major biomarkers. Atopic responses following certain pathogens such as Porphyromonas gingivalis is currently an area of interest for further research. PurposeThe aim of this study is to measure the level of IgE, IgG4, and IgG4/IgE ratio periodically after exposure of periodontal pathogen Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS). MethodsWe used 16 wistar rats (Rattus norvegicus) randomly subdivided into 4 groups, group 1 were injected by placebo, group 2 by LPS Pg 0.3 g/mL,group 3 by LPS Pg 1 g/mL, and group 4 by LPS Pg 3 g/mL. Sera from both groups were taken from retro-orbital plexus before and after exposure. ResultsLevel of IgE and IgG4 increased significantly following exposure of LPS Pg at day-4 and day-11. Greater increase of IgE rather than IgG4 contributes to rapid decline of IgG4/IgE ratio, detected in the peripheral blood at day-4 and day-11. ConclusionModulation of atopic responses following exposure to LPS Pg is reflected by decrease in IgG4/IgE ratio that accompanies an increase of IgE. Clinical significancePorphyromonas gingivalis, a keystone pathogen during periodontal disease, may have a tendency to disrupt atopic biomarkers.