Skin-Derived ABCB5 + Mesenchymal Stem Cells for High-Medical-Need Inflammatory Diseases: From Discovery to Entering Clinical Routine.

The ATP-binding cassette superfamily member ABCB5 identifies a subset of skin-resident mesenchymal stem cells (MSCs) that exhibit potent immunomodulatory and wound healing-promoting capacities along with superior homing ability. The ABCB5 MSCs can be easily accessed from discarded skin samples, expanded, and delivered as a highly homogenous medicinal product with standardized potency. A range of preclinical studies has suggested therapeutic efficacy of ABCB5 MSCs in a variety of currently uncurable skin and non-skin inflammatory diseases, which has been substantiated thus far by distinct clinical trials in chronic skin wounds or recessive dystrophic epidermolysis bullosa. Therefore, skin-derived ABCB5 MSCs have the potential to provide a breakthrough at the forefront of MSC-based therapies striving to fulfill current unmet medical needs. The most recent milestones in this regard are the approval of a phase III pivotal trial of ABCB5 MSCs for treatment of recessive dystrophic and junctional epidermolysis bullosa by the US Food and Drug Administration, and national market access of ABCB5 MSCs (AMESANAR) for therapy-refractory chronic venous ulcers under the national hospital exemption pathway in Germany.