Given their vast proliferative potential, immunosuppressive properties and the ease of access to available tissue sources, therapies with autologous or allogeneic MSCs have been tested in a variety of immune-mediated disease models. Results have been mainly encouraging, but not altogether consistent, particularly in the case of arthritis.

At the time of this review, 228 MSC registered human trials were found at the National Institutes of Health (NIH) website, including 19 for graft—versus—host disease (GVHD), 18 for diabetes, 11 for Crohn's disease or ulcerative colitis, 7 for multiple sclerosis, 3 for amyotrophic lateral sclerosis, one each for Sjogren syndrome, rheumatoid arthritis and systemic sclerosis and 3 for SLE (http://clinicaltrials.gov/). Some of these trials point to non immune-mediated conditions associated with tissue injury such as hepatic cirrhosis, myocardial infarction or congestive heart failure. In several of these instances it has become apparent that MSCs are not necessarily replacing diseased tissues or differentiating into separate cell lineages but rather exert a complex pattern of trophic, regenerative and anti-inflammatory effects.