Gelsolin down-regulates lipopolysaccharide-induced intraamniotic tumor necrosis factor-α production in the midtrimester of pregnancy

Objective The purpose of this study was to identify gelsolin in midtrimester amniotic fluid and evaluate its interaction with lipopolysaccharide (LPS). Study Design Supernatants from 40 midtrimester amniotic fluid samples were incubated with Escherichia coli LPS, and gelsolin binding was measured by enzyme-linked immunosorbent assay. Unfractionated aliquots of 25 of the fluids were cultured ex vivo for 24 hours in the presence of LPS and supernatants tested for tumor necrosis factor (TNF)-α and interleukin (IL)-10 production, and the influence of antigelsolin antibody was evaluated. Results Each amniotic fluid was positive for gelsolin that bound to LPS. LPS-induced TNF-α production was inversely proportional to the amniotic fluid concentrations of LPS-bound gelsolin (r = -0.5047; P = .006). Preincubation with monoclonal antibody to gelsolin led to an increase in LPS-induced TNF-α production ( P = .01). There was no relationship between gelsolin and IL-10 production. Conclusion Gelsolin is present in midtrimester amniotic fluid, binds to LPS, and inhibits the induction of TNF-α.