Toran, Jose LuisAguilar, SusanaLopez, Juan AntonioTorroja, CarlosQuintana, Juan A.Santiago, CesarAbad, José LuisGomes-Alves, PatriciaGonzalez, AndresBernal, Juan AntonioJimenez-Borreguero, Luis J.Alves, Paula MarquesR-Borlado, LuisVazquez, JesusBernad, Antonio2018-11-052018-11-052017-10-02Sci Rep. 2017; 7(1):124902045-2322http://hdl.handle.net/20.500.12105/6567Studies in recent years have established that the principal effects in cardiac cell therapy are associated with paracrine/autocrine factors. We combined several complementary techniques to define human cardiac progenitor cell (CPC) secretome constituted by 914 proteins/genes; 51% of these are associated with the exosomal compartment. To define the set of proteins specifically or highly differentially secreted by CPC, we compared human mesenchymal stem cells and dermal fibroblasts; the study defined a group of growth factors, cytokines and chemokines expressed at high to medium levels by CPC. Among them, IL-1, GROa (CXCL1), CXCL6 (GCP2) and IL-8 are examples whose expression was confirmed by most techniques used. ELISA showed that CXCL6 is significantly overexpressed in CPC conditioned medium (CM) (18- to 26-fold) and western blot confirmed expression of its receptors CXCR1 and CXCR2. Addition of anti-CXCL6 completely abolished migration in CPC-CM compared with anti-CXCR2, which promoted partial inhibition, and anti-CXCR1, which was inefficient. Anti-CXCL6 also significantly inhibited CPC CM angiogenic activity. In vivo evaluation also supported a relevant role for angiogenesis. Altogether, these results suggest a notable angiogenic potential in CPC-CM and identify CXCL6 as an important paracrine factor for CPC that signals mainly through CXCR2.engVoRhttp://creativecommons.org/licenses/by-nc-sa/4.0/CXCL6Cardiac progenitor cellsProteomicsSecretomeAtribución-NoComercial-CompartirIgual 4.0 Internacional28970523711249010.1038/s41598-017-11976-62045-2322Scientific reportsopen access