Intrauterine inflammation during pregnancy can cause prenatal brain injury, and is associated with preterm birth. Gardnerella vaginalis (GV) is a gram variable rod associated with bacterial vaginosis, pelvic inflammatory disease, bacteremia, and preterm birth. Bacterial vaginosis samples demonstrate up-regulation of Toll-like Receptor 2 and 4 mRNA and secretion of IL-1β in cultured trophoblasts. It has not been clearly demonstrated that isolated GV specimens are capable of the characteristic inflammatory downstream effectors in monocytes. We set out to determine if GV causes inflammatory effector recruitment and expression of proinflammatory cytokines in a human monocyte cell line, THP-1. An ASC-YFP overexpression system was used for immunofluorescent detection of inflammasome components, the Annexin-V apoptosis assay was used for viability, and cytokine levels were quantified by ELISA. Immunofluorescent detection showed co-localization of both NLRP3 and NLRC4 with ASC-YFP in GV-treated and LPS/ATP-treated cells. GV-treated cells exhibited a statistically significant IL-1β, IL-18, and TNFα response over untreated cells, however, IL-18 was significantly increased compared to LPS/ATP treatment. GV-treated cells remained viable through 24 h which demonstrates that GV causes significant cytokine elevation in THP-1 cells, without significant cell death. These results suggest that GV infection may lead to significant sequelae by production of proinflammatory cytokines.
- Copyright © 2013 by The American Association of Immunologists, Inc.