Oral infection and adverse pregnancy outcome: porphyromonas gingivalis outer membrane vesicles enter trophoblast cells and alter trophoblast-monocyte interaction

B LARA F MERECH, L GLIOSCA, MS GORI, L FERNANDEZ, D VOTA, G CALO, R RAMHORST, C PÉREZ LEIRÓS, V HAUK

Buenos Aires

Congreso; Reunión Anual Conjunta SAIC-SAI-SAFIS; 2021

An association between periodontitis and deep placentation dis-orders has been reported although the mechanisms remain un-clear. Porphyromonas gingivalis (Pg) is among the most relevant pathogens in periodontal disease. Pg produces and releases outer membrane vesicles (OMVs). The production of OMVs is involved in bacterial functions and has a role in pathogenesis. During placen-tation, trophoblast cells secrete cytokines and chemokines in order to interact with immune cells and maintain immune homeostasis. Al-terations in this interaction associate with pregnancy complications. In this work, we analyzed the effect of Pg-OMVs on trophoblast cell function. OMV were isolated by ultracentrifugation and labelled with PKH26 dye for uptake assays. OMVs were characterized using dynamic light scattering and transmission electron microscopy and were on the nanometric size range (108 ±39 nm). Swan-71 and HTR-8 tro-phoblast cells were treated with 0.1-10 ug/ml Pg-OMV for 2-24h de-pending on the assay. MTT assay was used to evaluate cell viability. To test trophoblast?monocyte interaction, monocytes were isolated from healthy volunteers using Percoll gradient and incubated with trophoblast conditioned media (Tb-CM). We found that Pg-OMVs were internalized by HTR-8 and Swan-71 trophoblast cells in a time and concentration dependent manner without affecting cell viability. Inhibition of actin polymerization by cytochalasin D reduced the uptake of Pg-OMVs. Regarding immune homeostasis maintenance, increased mRNA expression of IL-1beta, MCP-1, RANTES was found in Pg-OMV treated trophoblast cells. In addition, Tb-CM of Pg-OMV treated cells decreased the frequency of IL-10 + CD14+ monocytes (p