Assessing the Effects of Dasatinib on Mesenchymal Stem/Stromal Cells.

Introduction: Progressive aging, or senescence, of mesenchymal stem/stromal cells (MSCs) is a major obstacle faced when trying to culture potent stem cells for use in therapy. Senescent cells are irreversibly nondividing cells that cease performing critical functional effects. Elimination of senescent cells using biochemical means, such as the use of senolytic drugs like dasatinib, may be useful in retaining the viable and proliferating populations of the cells. Methods: An in vitro approach was used to investigate the effect of dasatinib on phenotypic, genotypic, and immunomodulatory functionality of osteogenic and adipogenic differentiated MSCs. Replicative senescence was achieved through multiple sub-culturing in vitro, then senescent and non-senescent cultures were treated with a standard dosage of dasatinib. MSCs were then differentiated into osteogenic, adipogenic or chondrogenic cultures using conditioned media to be tested for the three criteria being investigated. Results: Significant changes were observed in these criteria, indicated by evidence gathered from proliferation and indoleamine 2,3 dioxygenase activity assays. Phenotypic results of dasatinib were shown to reduce the population of senescent MSCs while allowing non-senescent MSCs to continue differentiating and proliferating without interference from senescent cells. Genotypic results showed no change to upregulation in markers associated with osteogenic and adipogenic cells when exposed to dasatinib. Indoleamine Dioxygenase activity showed insignificant differences in cells exposed to dasatinib versus control groups, providing evidence against compromised cellular immune function. Conclusion: This investigation provides insight into how dasatinib effects MSCs functional ability and provides a better understanding of the function of senolytic agents.