The therapeutic potential of FoxP3+ Treg cells has been demonstrated in many preclinical models and clinical trials aiming to prevent graft-versus-host disease during organ transplantation and in several autoimmune diseases such as type 1 diabetes mellitus, inflammatory bowel disease, systemic lupus erythematosus, multiple sclerosis, and allergy (103). The gene discussed is FOXP3; the disease is multiple sclerosis.