Cytokine Priming Enhances the Antifibrotic Effects of Mesenchymal Stromal Cells Conditioned Medium Via Fibrogenic Myofibroblasts Elimination and Extracellular Matrix Degradation.

Fibrosis is a pathological scarring process characterized by persistent myofibroblasts activation with excessive accumulation of extracellular matrix (ECM). Fibrotic disorders represent an increasing burden of disease-associated morbidity and mortality worldwide for which there are limited therapeutic options. Reversing fibrosis requires the elimination of myofibroblasts, remodeling of the ECM, and regeneration of functional tissue. Multipotent mesenchymal stromal cells (MSC) have antifibrotic properties mediated by secreted factors present in their conditioned medium (MSC-CM). However, there are no standardized in vitro assays to predict the antifibrotic effects of human MSC, and, as a consequence, we lack evidence on the effect of cytokine priming on MSC’s antifibrotic effects. We hypothesize that the MSC-CM promotes fibrosis resolution in vitro and that this effect is enhanced following MSC cytokine priming.