Immune ablation and stem-cell therapy in autoimmune disease. Experimental basis for autologous stem-cell transplantation.

Treatment of rats suffering from florid chronic progressive systemic arthritis or from chronic remitting/relapsing encephalomyelitis with autologous bone marrow transplantation (BMT) is highly effective. This finding was unexpected as the genotype of the bone marrow largely determines the susceptibility of both spontaneous and induced autoimmune diseases in rodents. The success of autologous stem-cell transplantation depends on the completeness of eradication of the effectors of autoimmune disease, in other words activated and memory T lymphocytes. The reviewed experimental data, when translated to the clinic, indicate that the patients should be subjected to a conditioning regimen that induces maximal lymphoablation and that the autologous transplant has to be T-cell depleted.