Mesenchymal Stem Cells for Frailty?

Frailty is a medical syndrome associated with advancing age characterized by reduced functional reserve, strength, endurance, and susceptibility to infection associated with high morbidity, hospitalization, and death. Nonspecific interventions to improve the healthspan of affected patients include physical therapy, exercise, improved nutrition, etc. Among the hallmarks of aging, depletion of stem cells with resultant compromise of regeneration and repair of tissues informs a rational stem cell-based replacement strategy. This hypothesis has been evaluated in a randomized, double-blind, placebo-controlled clinical trial utilizing human allogeneic mesenchymal stem cells (allo-hMSCs), a facile, scalable stem cell replacement therapy. Intravenous infusion of 100 or 200 million allo-hMSCs was deemed safe in aged frail individuals. However, modest improvement outcomes were limited to the lower dose, a finding that remains difficult to explain. Future studies are definitely warranted given the magnitude of this increasingly important medical syndrome.