Increased expression of alpha-enolase in cervico-vaginal fluid during labour

OBJECTIVES: The aim of this study was (i) to characterise differentially expressed proteins in cervico-vaginal fluid (CVF) at the time of preterm labour onset and (ii) to confirm these studies in human CVF samples taken from women before and during spontaneous labour. STUDY DESIGN: Preterm labour was induced in sheep (n = 5) via fetal dexamethasone infusion (1 mg/24 h). CVF samples were taken prior to dexamethasone infusion (0 h), 28 h after the start of dexamethasone infusion, and immediately prior to delivery. Two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify differentially expressed proteins. For the human studies, paired CVF samples were taken 5-9 days before labour and during spontaneous labour onset (n = 7). RESULTS: There was a 4.2-fold increase in alpha-enolase protein expression in sheep CVF during labour. Likewise, alpha-enolase protein expression was significantly increased during spontaneous human labour at term. CONCLUSIONS: Alpha-enolase is known to be bound to neutrophils and interact in the immune response, and thus may play a role in inflammation associated with human labour.