Non-myeloablative stem cell transplantation for autoimmune diseases

Treatment of life-threatening autoimmune diseases in animal models with induced or spontaneous autoimmune diseases can be accomplished by a 2-step procedure involving elimination of self-reactive lymphocytes with an immune ablative conditioning regimen followed by infusion of autologous or allogeneic stem cells, respectively. In animal models it was shown that using such a strategy, autoimmunity could be adequately controlled. It is speculated that de-novo development of the T and B cell repertoire from uncommitted progenitor cells in the presence of the autoantigens may be the best recipe for re-induction of self-tolerance, similarly to the normal ontogeny of the immune system during the induction of self tolerance in fetal stage. For both autologous and allogeneic hematopoietic stem cell transplantation, a non-myeloablative stem cell transplantation (NST) regimen may be used for safer lymphoablation rather than myeloablation. In addition, for allogeneic hematopoietic stem cell transplantation engraftment of disease resistant donor stem cells will alter the genetic predisposition towards autoimmune disease susceptibility.