Conditioning of maternal monocytes to myeloid regulatory cells by endometrial stromal cellsRY CELLS BY ENDOMETRIAL STROMAL CELLS

SOLEDAD GORI

Congreso; IX SLIMP 2022; 2022

INVITADA COMO ORADORA PARA WORKSHOP. Human reproduction is a highly complex process and pregnancy is a real challenge for maternal immune system. In this sense, a successful implantation requires a dialogue involving a receptive endometrium, a competent embryo and “educated” maternal immune system. During the decidualization program, endometrial stromal cells suffer endoplasmic reticulum stress (ERS) and unfolded protein response (UPR), allowing the secretion of immunoregulatory factors which may condition maternal leukocytes to a regulatory profile. In the last years, Myeloid Regulatory Cells (MRCs) have been proposed as a heterogeneous set of immunosuppressors and tolerance-inducers. DC-10 is a novel and distinctive subset of MRCs characterized to be a potent IL-10 producer and Tr1 cells-inducer through HLA-G pathway. DC-10 and HLA-G+ T cells were found increased in decidua of first trimester; however, little is known about their induction. Therefore, in the last years we wonder if decidualization program conditions the differentiation of maternal monocytes to MRCs subsets. Briefly, we showed that decidualized cells promotes the differentiation of DC-10 able to induce HLA-G+ T cells that might play an immunoregulatory role in embryo implantation. Also, we observed that ERS might be transmitted from stromal cells to monocytes and its fine balance is required to maintain the tolerogenic microenvironment.This work was funded by the National Agency of Sciences and Technology ANPCyT (PICT 2017-2978 to SG and PICT 2018-2461 to RR) and University of Buenos Aires (UBACyT 20020090200034 to RR). The authors have no conflicts of interest to disclose.