1:Centro de Cirugía de Mínima Invasión Jesús Usón; 2:RICORS-TERAV Network; 3:Immunology Unit, University of Extremadura; 4:Institute of Molecular Pathology Biomarkers, University of Extremadura

Mesenchymal stromal cells isolated from menstrual blood (MenSCs) currently represent a valuable therapeutic tool due to their biological activity, including angiogenic properties, and for being a source of mesenchymal stem cells (MSCs) with easy isolation, high proliferation rate, low immunogenicity, and no ethical conflicts. The secretome from these cells shares the therapeutic capacity of their progenitor cells with additional advantages such as being a more stable treatment with lower immunogenicity. Thus, the aim of this work was to evaluate the functional effect of the secretome on human umbilical vein endothelial cells (HUVEC).  For this purpose, proliferation was analyzed by CCK8 and functional angiogenesis assays (migration, wound closure, and tube formation) were performed. All assays were performed with a secretome concentration of 100 µg/mL and 24 hours of co-culture. M199 +1% FBS medium was used as negative control (NC) and supplemented endothelial cell growth medium (EGM2) as positive control (PC). The results obtained were statistically compared with the NC. A significant increase in proliferation rate (p value = < ,01), migration rate (p value < ,001), and tube formation (p value < ,01) was observed. The wound assay showed a significantly higher closure capacity (p value < ,0001), similar to that observed in CP. All the results obtained demonstrate the angiogenic properties of the secretome from MenSCs and corroborate  the role of the secretome as a potential tool in regenerative therapies.