Longitudinal modulation of immune system cytokine profile during pregnancy

Objective: To characterize immune modulation as expressed by cytokine assays at three time-points in human pregnancy. Study design: This is a prospective, longitudinal study of a broad panel of cytokine expression during singleton pregnancies resulting in an uncomplicated, full-term, live births. Peripheral blood was obtained at 8-14, 18-22, and 28-32. weeks gestation. Six cytokines - IFN-γ, IL-4, TNF-α, IL-1β, IL-6, and IL-10 - were measured in supernatants obtained from whole blood stimulations with PHA or LPS and were compared to unstimulated controls. Samples were processed by Luminex-100 MAP®. We used Generalized Linear Models (GLM) to evaluate cytokine trajectories. Results: Complete data were obtained for 45 uncomplicated pregnancies. Overall, peripheral blood WBC's demonstrated dampened cytokine responses. However, over the course of pregnancy, we found enhanced counter-regulatory cytokine expression (e.g., shown by increased IL-10). Conclusion: The overall decrease in pro-inflammatory cytokines and increase in counter-regulatory cytokines as uncomplicated pregnancy progresses supports the evolving concepts of immunoregulation for the maintenance of a viable pregnancy.