MDSCs in pregnancy and pregnancy-related complications: an update

Abstract

Maternal-fetal immune tolerance is a process that involves complex interactions of the immune system, and myeloid-derived suppressor cells (MDSCs) have emerged as one of the novel immuno-modulator in the maintenance of maternal-fetal immune tolerance. MDSCs are myeloid progenitor cells with immunosuppressive activities on both innate and adaptive cells through various mechanisms. Emerging evidence demonstrates the accumulation of MDSCs during healthy pregnancy to establish maternal-fetal immune tolerance, placentation, and fetal-growth process. In contrast, the absence or decreased MDSCs in pregnancy complications like preeclampsia, preterm birth, stillbirth, and recurrent spontaneous abortion has been reported. Here, we have summarized the origin, mechanisms, and functions of MDSCs during pregnancy along with the recent advancements in this dynamic field. We also shed light on the immunomodulatory activity of MDSCs, which can be a foundation for potential therapeutic manipulation in immunological pregnancy complications.

Kisspeptin prevents pregnancy loss by modulating the immune microenvironment at the maternal‐fetal interface in recurrent spontaneous abortion

“…MDSCs were decreased in the peripheral blood and the endometrial tissues of patients with a history of miscarriage. 28,35 The reduction in MDSCs during a miscarriage could potentially result in decreased Treg levels, subsequently resulting in failed maternal-fetal immune tolerance. 35 Hence, changes in MDSC cells were simultaneously assessed while detecting Treg cells.…”

“…25 Myeloid-derived suppressor cells (MDSCs), also known as CD11b + Gr-1 + cells, 26 are an important group of immunosuppressive cells at the maternal-fetal interface, 27 which are involved in maternal-fetal immune tolerance, placental development, and fetal growth during pregnancy. 27,28 Moreover, a study has opined that the adoptive transfer of MDSCs could improve murine pregnancy outcomes. 29 However, relevant research on MDSCs and RSA remains limited.…”

Myeloid‐derived suppressor cells in the therapy of autoimmune diseases

“…A heterogeneous population of myeloid cells, termed myeloidderived suppressor cells (MDSC), was described as pathologically differentiated/ activated monocytes and neutrophils [5]. Although initially defined in solid tumors, subsequent discoveries described their roles in different pathological and physiological conditions, including chronic inflammation, sepsis, obesity, aging, and pregnancy (reviewed in [6][7][8][9]). Initially, early studies suggested that nonspecific suppressor cells play a significant role in autoimmunity [10].…”