LIPOPOLYSACCHARIDE-BINDING PROTEIN AND SOLUBLE CD14 RECEPTOR PROTEIN IN AMNIOTIC-FLUID AND CORD-BLOOD IN PATIENTS AT TERM

OBJECTIVES: Our purpose was to examine whether lipopolysaccharide bind ing protein and soluble CD14 are present in amniotic fluid and to dete rmine whether the lipopolysaccharide binding protein and soluble CD14 concentrations are associated with indicators of infection or labor at term, a lipopolysaccharide-lipopolysaccharide binding protein complex activates macrophages through soluble CD14 at lipopolysaccharide conc entrations up to 100 times lower than required with lipopolysaccharide alone. Thus lipopolysaccharide binding protein and soluble CD14 in am niotic fluid could explain the high concentrations of cytokines found in amniotic fluid of culture-positive patients and may even explain th e presence of cytokines in some culture-negative patients, STUDY DESIG N: Healthy women at term undergoing cesarean section had amniotic flui d, chorioamnion, decidua, and cord blood obtained. Lipopolysaccharide binding protein was measured by enzyme-linked immunosorbent assay. Amn iotic fluid was cultured and assayed for cytokines, and the chorioamni on and decidua were cultured and examined histologically, RESULTS: Lip opolysaccharide binding protein and soluble CD14 were present in all a mniotic fluids and fetal cord blood. An elevated level of lipopolysacc haride binding protein (270 ng/ml/mg of protein) was present in the am niotic fluid of 12 (36%) of the 33 patients. An elevated level was ass ociated with microorganisms in the chorioamnion and decidua, cytokines (tumor necrosis factor-alpha, interleukin-6, and interleukin-8) in am niotic Fluid, histologic chorioamnionitis, and labor. Among patients i n labor, the concentration of lipopolysaccharide binding protein appea red independent of microorganisms in the amniotic fluid. CONCLUSIONS: Lipopolysaccharide binding protein and soluble CD14 are present in amn iotic fluid, and concentrations of lipopolysaccharide binding protein are elevated in patients in labor with and without evidence of infecti on. Lipopolysaccharide binding protein and soluble CD14 may mediate in trauterine inflammatory responses at term.