Soluble MHC antigens isolated from syngeneically pregnant mice promote cellular immunity

Abstract

Background: Ultrasound measurement of the uterine cervix is a well-established method in the prediction of preterm labor. The sensitivity and positive predictive value of ultrasound cervicometry still remain rather unsatisfactory. Recent discoveries suggest that T regulatory lymphocytes (CD4+CD25+CD127-Tregs)might play an important role in the pathophysiology of preterm labor. The aim of this study was to assess the relationship among maternal circulating Tregs, the sonographically measured uterine cervix, and the risk of preterm labor. Methods:Atotal of 60womenwith regular contractions and/or cervical incompetence were included in a prospective longitudinal cohort study. All patients at recruitment were between 24 and 32 weeks of gravidity. A peripheral blood sample was drawn from the cubital vein to the tube with the sodiumheparin directly after the ultrasound vaginal cervicometry and was analyzed within 4h. Following clinical outcomes were recorded in all subjects: delivery within 48h of the examination; delivery before week 34; and delivery before pregnancy week 37. Results: Using pooled Treg and cervical length data from all the cohorts examined, unadjusted odds ratios for preterm delivery were counted. The risk of preterm labor happening within 48h of testing was demonstrated to be almost 35 times higher (OR=35.21, CI 13.3; 214, p<0.001) in the groupwith simultaneously lowTreg values (0.031×109/L) and a shortened uterine cervix (17.5mm), compared with the situation where both of these values were normal. We found similar results when combining the predictive value of Treg levels with cervical measurement in predicting preterm delivery before 34 aswell as 37 weeks. Conclusions: The odds that preterm delivery will occur given a short cervix and low Treg count is significantly higher than odds in other combinations and/or separate test measurements. Our results may offer potential clinical application of a combined assessment of Treg count and cervical measurement in patients who present with risk factors for preterm labor. However, further studies are required to elucidate the functional significance of these findings.