Human predecidual stromal cells are mesenchymal stromal/stem cells and have a therapeutic effect in an immune-based mouse model of recurrent spontaneous abortion Muñoz Fernandez, Raquel Mata, Claudia de la Requena Guerrero, Francisco Martín, Francisco Fernández Rubio, Pablo Llorca, Tatiana Ruiz-Magaña, María José Ruiz Ruiz, María Carmen García Olivares, Enrique Fernando Clone cells Immune tolerance Mesenchymal stromal cells Predecidual stromal cells Recurrent abortion Human decidual stromal cells (DSCs) are involved in the maintenance and development of pregnancy, in which they play a key role in the induction of immunological maternal–fetal tolerance. Precursors of DSCs (preDSCs) are located around the vessels, and based on their antigen phenotype, previous studies suggested a relationship between preDSCs and mesenchymal stromal/stem cells (MSCs). This work aimed to further elucidate the MSC characteristics of preDSCs. Under the effect of P4 and cAMP, the preDSC lines and clones decidualized in vitro: the cells became rounder and secreted PRL, a marker of physiological decidualization. PreDSC lines and clones also exhibited MSC characteristics. They differentiated into adipocytes, osteoblasts, and chondrocytes, and preDSC lines expressed stem cell markers OCT- 4, NANOG, and ABCG2; exhibited a cloning efficiency of 4 to 15%; significantly reduced the embryo resorption rate (P < 0.001) in the mouse model of abortion; and survived for prolonged periods in immunocompetent mice. The fact that 3 preDSC clones underwent both decidualization and mesenchymal differentiation shows that the same type of cell exhibited both DSC and MSC characteristics. Together, our results confirm that preDSCs are decidual MSCs and suggest that these cells are involved in the mechanisms of maternal–fetal immune tolerance 2019-10-25T11:33:24Z 2019-10-25T11:33:24Z 2019 info:eu-repo/semantics/article Muñoz-Fernández, R., De La Mata, C., Requena, F., Martín, F., Fernandez-Rubio, P., Llorca, T., ... & Olivares, E. G. (2019). Human predecidual stromal cells are mesenchymal stromal/stem cells and have a therapeutic effect in an immune-based mouse model of recurrent spontaneous abortion. Stem cell research & therapy, 10(1), 177. http://hdl.handle.net/10481/57529 10.1186/s13287-019-1284-z eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer Nature