Immunoregulatory Effects of Human Amnion Epithelial Cells on Natural Killer and T Cells in Women with Recurrent Spontaneous Abortion (RSA)

Introduction: Unexplained Recurrent Spontaneous Abortion (URSA) is the most common immunological complication during pregnancy. It has been found that the cells such as human amnion epithelial cells (hAECs) have the potency to modulate immune responses in vitro and in vivo. In the present study, we assessed the immunomodulatory effect of hAECs on NK cells and T cells in women with URSA. Materials and Methods: Peripheral Blood mononuclear cells (PBMC) were obtained from 14 URSA patients and co-cultured with isolated hAECs. NK cells and T cells were identified using anti-CD56 and anti-CD3 monoclonal antibodies (mAb). The expression of the activating receptor CD69 and the degranulation marker CD107a on NK cells and T cells were detected using specific mAb and analyzed by flow cytometry. Results: We found that CD69 activating receptor expression on NK cells and T cells was significantly decreased by incubation with hAECs in a dose-dependent manner (p=0.049). Also, the degranulation marker CD107a was significantly downregulated on NK cells and T cells following incubation with hAEC (p=0.003). Conclusion: Our results suggest hAECs have immune regulatory effects on activation and cytotoxicity of NK and T cells. Potential therapeutic application of hAECs for dysregulated NK and T cells immunity should be investigated in the future.