Immunological aspects of mesenchymal stem cell therapy for ALS

Neuroinflammation contributes to ALS progression, yet effective immune-modulating therapies remain limited. Despite the enthusiasm regarding stem cell therapy as a means of regeneration, it is interesting that the first FDA approval for mesenchymal stem cells (MSC) was for immune modulation, graft versus host disease (GVHD), not rejuvenation. We focus here on the immunological mechanisms through which MSC, particularly via induction of regulatory T cells, may slow progression of amyotrophic lateral sclerosis (ALS), a uniformly fatal motor neuron disease. Clinical results to date have been mixed, and we argue that prospective monitoring of immune and blood-based biomarkers could sharpen patient selection, guide choice of cell type and adjuvant, and calibrate treatment intensity. MSC-induced Tregs may suppress neuroinflammation and offer a strategy to slow ALS progression.