Association between vaginal 70-kd heat shock protein, interleukin-1 receptor antagonist, and microbial flora in mid trimester pregnant women

OBJECTIVE: This study investigated the association among the inducible 70-kd heat shock protein, cytokines, and microbial flora in the vagina in mid trimester pregnant women and subsequent preterm delivery. STUDY DESIGN: Vaginal samples from 205 pregnant women, which were collected at 18 to 22 weeks of gestation, were analyzed for qualitative and quantitative vaginal microflora and for 70-kd heat shock protein, interleukin-1beta, interleukin-1 receptor antagonist, and tumor necrosis factor-alpha by enzyme-linked immunosorbent assay. Pregnancy outcome data were obtained subsequently. RESULTS: The 70-kd heat shock protein was detected in 38 vaginal samples (18.5%). Its presence was associated with elevated vaginal pH, a diagnosis of bacterial vaginosis, and elevated interleukin-1 receptor antagonist levels (P < .001). Among women with bacterial vaginosis, 70-kd heat shock protein-positive subjects had a >80% increase in median vaginal concentration of interleukin-1 receptor antagonist (P < .05). CONCLUSION: Vaginal 70-kd heat shock protein expression is associated with the down-regulation of the proinflammatory immune response to abnormal vaginal flora in mid trimester pregnant women.