IL-7/IL-7R signaling pathway might play a role in recurrent pregnancy losses by increasing inflammatory Th17 cells and decreasing Treg cells.

Problem: We aim to investigate a possible role of IL-7/IL-7R signaling pathway in recurrent pregnancy losses (RPL).
Material and Methods: Using the abortion-prone (AP) and non-abortion-prone (NP) mice model, fetal resorption rates (FRR), Th17 and Treg cells-related factors, and the effect of IL-7 and IL-7R antagonist were investigated by flow cytometry, quantitative real-time PCR, and immunohistochemistry. IL-7 and IL-7R expressions in human decidua were investigated by immunohistochemistry.
Results: In the AP mice, IL-7R antagonist treatment significantly decreased FRR by downregulating Th17 and upregulating Treg-related factors. When the NP mice were treated with IL-7, FRR was significantly increased by upregulating Th17 and downregulating Treg-related factors. In decidual stromal cells of women with RPL, increased IL-7 and decreased IL-7R expressions were present when compared to normal controls.
Conclusion: IL-7/IL-7R signaling pathway plays a possible role in RPL by upregulating Th17 immunity, meanwhile downregulating Treg immunity. Regulation of IL-7/IL-7R may be a new therapeutic strategy for RPL.
(© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)