More Bang for Your Buck: “Off-The-Shelf” Solutions for Cell Replacement Therapy

The immune barrier to transplantation has widely been recognized as the ultimate hurdle to the translation of stem cell-based therapies. In particular the polymorphic nature of the human leucocyte antigens (HLA) poses an imminent barrier to the successful engraftment of cells from other than autologous sources. To make stem cell therapies available to a larger pool of patients and a commercially viable option several groups have attempted to create hypoimmunogenic “universal” donor stem cells that evaded immune detection. The goal of this commentary is to give a brief overview of the current approaches taken and discuss challenges that need to be addressed to turn such cells into a viable commercial option.