Mesenchymal Stromal Cells: What are the secrets of their secretome?

Multipotent Mesenchymal Stromal Cells (MSCs) are multipotent adult cells that can be isolated from different tissues. The current hypothesis supports that the main MSCs action mechanism relates to its paracrine activity, creating a microenvironment with trophic signals. However, preclinical studies with different sources of MSCs and different animal models have shown conflicting results. Therefore, the evaluation of these cells secretome content is of great interest. Here we analyzed the secreted proteins of MSCs, isolated from 3 different sources (adipose tissue, uterine tubes and skeletal muscle), obtained from 5 different donors. Following MSCs characterization, proteins secreted in serum-free conditions (conditioned media, CM) were analyzed by mass-spectrometry-based quantitative proteomics.