MATERNAL LEVELS OF SERUM-SOLUBLE CDS AND IL-2R ARE NOT SIGNIFICANTLY ELEVATED IN IDIOPATHIC PRETERM LABOR

Objective: To search for evidence of immune activation in idiopathic p reterm term labour by measuring the soluble markers of T cell activati on, CD8 (sCD8) and interleukin-2 receptor (sIL2R). Design : Serum sCD8 and sIL-2R were measured by commercial ELISA in subjects undergoing i diopathic preterm labour (PTL; n=15) and normal term labour (TL; n=17) . Two gestationally equivalent non-labouring groups were also included representing preterm (PTC; n=10) and term (TC; n=10)controls. Possibl e delayed responses in soluble activation markers were monitored in bl ood samples taken 48 h after delivery in both labouring groups (PTLp; n=9: TLp; n=9). Results: (1) Excluding the 48 h postpartum samples, no statistically significant differences were revealed following a Krusk all-Wallis analysis of variance (ANOVA) for levels of sIL-2R (P=0.093) and sCD8 (P=0.098). Including the postpartum samples, however, gave s tatistically significant differences for each (sIL-2R: P=0.033; sCD8: P=0.006). (2) No statistically significant difference was revealed by direct comparison of the two labouring groups alone (Wilcoxon-Mann-Whi tney test: P > 0.05). (3) Significantly lower levels of sCD8 were foun d in the PTL subgroup which had histological evidence of inflammation (Wilcoxon-Mann-Whitney: P=0.003). Conclusions: Statistical analysis of our data suggests that idiopathic preterm labour is not commonly asso ciated with significant elevations in circulating sCD8 or sIL-2R level s compared with normal term labour. Where significant changes in the l evels of these markers do arise, our evidence points to a delayed effe ct of labour per se rather than infection as the most probable cause.