Cytokine profiling: variation in immune modulation with preterm birth vs. uncomplicated term birth identifies pivotal signals in pathogenesis of preterm birth

OBJECTIVES: To assess deviations in longitudinally measured cytokines with preterm birth (PTB). METHODS: Prospective longitudinal study targeting 80 subjects. Phlebotomy specimens for broad panel of cytokine analysis were obtained at three time (T) intervals: first trimester (T1: 8–14 weeks’ gestation), second trimester (T2: 18–22 weeks’ gestation), and third trimester (T3: 28–32 weeks’ gestation). Important demographics and outcomes were tracked. Data were stratified and the target groups were analyzed as follows: “Uncomplicated” (delivered ≥37 weeks) or “Preterm Birth” (<37 weeks). Generalized Linear Modeling determined rate of change T1–T3 by outcome. RESULTS: Complete data replete with phlebotomy at all three visits were obtained on 80 women. Birth outcomes were as follows: 11 Uncomplicated Term Birth (UTB), 28 PTB, 4 low birth weight (LBW), 16 OB complications (OBC), 11 current infections (IFN), and 10 mixed complications (MC=2 or more of the above). 28 PTB were compared to 11 uncomplicated term deliveries. In both groups, T helper type 1 (TH1) cytokine (IL-1β), pleiotrophic pro-inflammatory cytokine (IL-6), and counter-regulatory cytokine (IL-10) responses decreased over gestation, but rates of change in IL-1β, IL-6, and IL-10 were significantly different. Stratification of women by smoking status additionally demonstrated significant variance in immune status over the course of pregnancy CONCLUSIONS: Women delivering PTB demonstrated significant differences in cytokine trajectory over pregnancy; these data further validate key role played by immune regulation in directing pregnancy outcome. Likewise, smoking impacts longitudinal trajectory of cytokines over pregnancy.