IL-17 producing innate lymphoid cells 3 (ILC3) but not Th17 cells might be the potential danger factor for preeclampsia and other pregnancy associated diseases.

In pregnancy, the immunologic system plays an important role that ensures normal pregnancy development and can as well promote the development of complications. Pregnancy success appears to rely on a discrete balance between the Th cytokines, which are involved in fetal growth and development. Preeclampsia and gestational diabetes are known complications associated with pregnancy. However, the source of the increased IL-17 cytokine in preeclampsia and other pregnancy associated diseases still remains unclear amidst numerous inconsistencies. The recent identification of innate lymphoid cells (ILC) has raised more doubts about the sources of most of the Th associated cytokines. We investigated the source of peripheral IL-17 levels in preeclamptic, gestational diabetics and chronic diabetics compared to healthy pregnancy subjects. To evaluate the source of the increased IL-17 cytokine among preeclampsia, chronic diabetic and gestational diabetic patients we investigated the proportion of Th17 cell populations in peripheral blood mononuclear cells using flow cytometry as well as analyzing levels of IFN-γ, IL-17, IL-1β and HMGB1. This study found that the Th17 cell populations in peripheral blood of preeclamptic, gestational nor chronic diabetes during pregnancy did not correlate with the increased IL-17. We report that the increased IL-17 levels observed in patients with preeclampsia, gestational diabetes and chronic diabetes are associated with innate lymphoid cells 3 (ILC3) and may pose threats to the fetus if disregulated.