Cellular therapy for autoimmune diseases: Beyond autologous hematopoietic stem cell transplantation

Beyond autologous hematopoietic stem cell transplantation, an approach validated for the treatment of refractory multiple sclerosis and systemic sclerosis, cell therapy approaches based on the use of mesenchymal stem/stromal cells (MSCs) have been developed over the past two decades. These multipotent progenitors, easily isolated from adipose tissue, placenta, or Wharton jelly, display immunomodulatory and trophic (including anti-fibrotic) capacities that are promising in the treatment of various autoimmune diseases, including systemic sclerosis. The possibility of allogeneic approaches without prior conditioning, and the safety of their administration led to numerous clinical trials in the field, and the first authorizations in graft versus host disease and Crohn's disease. However, phase 3 trials are still awaited, as well as harmonization efforts and the development of functional tests predicting their efficacy, given the heterogeneity of these cellular products. The future may also be based on the use of MSC-derived extracellular vesicles and will undoubtedly integrate the biotechnological advances constituted by CARs (chimeric antigen receptor) in hematology, whose first applications have been reported notably in systemic lupus.