Fetal Weight And Oral Colonization With Porphyromonas Gingivalis

Abstract

Periodontitis in humans is associated with adverse pregnancy outcomes (APOs). However, periodontitis treatment trials (scaling and root planing) have not been successful at reducing the risk of APOs. Oral colonization with the periodontal pathogen Porphyromonas gingivalis leads to low fetal weight in C57BL/6J mice. We speculated that spread of P. gingivalis to the placenta of the C57BL/6J mouse would alter the placental microbiome, inducing local inflammation. We hypothesized that the frequency of P. gingivalis-specific CD4+ T cells producing IFN-γ in the uterine-draining (para-aortic) and oral draining (cervical) lymph nodes (PaLN-CLN) would correlate with low fetal weight in C57BL/6J mice. We discovered that frequency of P. gingivalis-specific CD4+ T cells producing IL-17A, IFN-γ, or IL-4 in PaLN-CLN of C57BL/6J (Jackson Labs) or C57BL/6UofM (In-House Bred) mice was not correlated with reduced fetal weight. Decreasing fetal weight was correlated with increasing amounts of P. gingivalis DNA in the placentas of C57BL/6J and C57BL/6UofM dams. BALB/cJ (Jackson), C57BL/6NCrl, and BALB/cAnNCrl (Charles River) mice harbored P. gingivalis DNA in their placentas but did not experience low fetal weight in response to oral colonization with P. gingivalis. Therefore, these results suggest that both microbiome and genetics are important in determining fetal weight outcomes in response to oral colonization with P. gingivalis.