Mesenchymal stromal cells express GARP/LRRC32 on their surface: effects on their biology and immunomodulatory capacity Carrillo Galvez, Ana Belen Cobo, Marien Cuevas Ocaña, Sara Gutiérrez Guerrero, Alejandra Sánchez Gilabert, Almudena Bongarzone, Pierpaolo García Pérez, Angélica Muñoz, Pilar Benabdellah, Karim Toscano, Miguel G Martin, Francisco Anderson, Per Anderson, Per Olof Glycoprotein A repetitions predominant Immunomodulation Leucine-rich repeat containing 32 Membrane bound TGF-β1 Mesenchymal stem cells Proliferation Mesenchymal stromal cells (MSCs) represent a promising tool for therapy in regenerative medicine, transplantation, and autoimmune disease due to their trophic and immunomodulatory activities. However, we are still far from understanding the mechanisms of action of MSCs in these processes. Transforming growth factor (TGF)-β1 is a pleiotropic cytokine involved in MSC migration, differentiation, and immunomodulation. Recently, glycoprotein A repetitions predominant (GARP) was shown to bind latency-associated peptide (LAP)/TGF-β1 to the cell surface of activated Foxp3(+) regulatory T cells (Tregs) and megakaryocytes/platelets. In this manuscript, we show that human and mouse MSCs express GARP which presents LAP/TGF-β1 on their cell surface. Silencing GARP expression in MSCs increased their secretion and activation of TGF-β1 and reduced their proliferative capacity in a TGF-β1-independent manner. Importantly, we showed that GARP expression on MSCs contributed to their ability to inhibit T-cell responses in vitro. In summary, we have found that GARP is an essential molecule for MSC biology, regulating their immunomodulatory and proliferative activities. We envision GARP as a new target for improving the therapeutic efficacy of MSCs and also as a novel MSC marker. 2024-09-23T06:44:03Z 2024-09-23T06:44:03Z 2015-01 journal article Carrillo-Galvez, Ana Belén et al. “Mesenchymal stromal cells express GARP/LRRC32 on their surface: effects on their biology and immunomodulatory capacity.” Stem cells (Dayton, Ohio) vol. 33,1 (2015): 183-95. doi:10.1002/stem.1821 https://hdl.handle.net/10481/94819 10.1002/stem.1821 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Oxford Academic