Development of small-molecule-induced fibroblast expansion technologies.

Dermal fibroblasts are responsible from the production of extracellular matrix and take role in the closure of skin wounds. Dermal fibroblasts are major cells of origin in the generation of induced pluripotent stem cells (IPSCs) and are historically being used as feeder layer and biofiller in the restorative surgeries. ex vivo expansion of the dermal fibroblasts provides a suitable model to study skin biology and to engineer bioartifical skins. Thus, development of efficient fibroblast expansion technologies gets outmost importance day by day. We sought to identify small molecules that induce ex vivo fibroblast expansion and understand their mechanisms. We analyzed the effect of 35 small molecules, which are expected to target molecular pathways involving cellular quiescence. We have found that small molecules, especially AS1949490 and SKF96365, increase human dermal fibroblast expansion of at least three different fibroblasts. Cell cycle analysis confirms that these small molecules allow cell cycle progression, as evident by increased percentage of cells in S-G -M phase of cell cycle. They led to a lower profile of apoptotic or necrotic fibroblasts. Intriguingly, we have found that identified small molecules could also endogenously induce the expression of IPSC generation, collagen synthesis, and aging-related genes. Identified small molecules may contribute to the induction of collagen synthesis in the biofiller products, the development of fibroblast products with better aging profile, and the improvement of IPSC generation.