Unveiling Human Cardiac Fibroblast Membrane Proteome.

Cardiac fibroblasts (CFs) are one of the main cell populations in the heart and play important roles in tissue homeostasis and myocardial fibrosis. The study of these cells has been hampered by the lack of reliable membrane markers: none of the antigens currently used for characterization and isolation of CFs is unique for this cell type. This issue has also raised doubts regarding a distinct identity of cardiac fibroblasts when compared to other myocardium cell populations with similar morphologies. In this work, we report a comprehensive description and functional analysis of human CFs (hCFs) membraneenriched fraction proteome by advanced mass spectrometry-based proteomic tools. A total number of 1478 proteins were identified, including 774 membrane proteins (52%). We also report the identification of a subset of 30 membrane proteins that in this workflow were only identified in hCFs by comparison with the membrane-enriched proteome lists of human cardiac stem cells, human mesenchymal stem cells, and human dermal fibroblasts. The data reported in this work are a valuable source of information for further studies aiming at defining a membrane molecular signature of human cardiac fibroblasts (hCFs), and a step forward in research regarding membrane proteins with key roles in hCF function in homeostasis and disease.