Clinically demonstrable anti-autoimmunity mediated by allogeneic immune cells favorably affects outcome after stem cell transplantation in human autoimmune diseases

To determine the role of allogeneic, autologous and syngeneic hemopoietic stem cell transplantation (SCTx) as a treatment for severe autoimmune disease (AID) we performed a literature search employing Medline, Cancer Lit and abstract books for reports on transplants for blood disorders and a concomitant AID. All reviews, case reports and abstracts available between June 1977 and September 2001 were used and attempts made to update them by e-mail by the corresponding authors. Disease-free survival (DFS) after allogeneic SCTx for 23 patients with severe aplastic anemia was 78% at 16 years and survival in unmaintained remission of concomitant AID was 64% at 13 years. DFS after allogeneic SCTx for 24 patients with hematologic malignancies was 87% at 15 years and survival in unmaintained remission for concomitant AID was 70% at 11 years. DFS after autologous SCTx for 24 patients with hematologic malignancies was 48% at 6 years and survival in unmaintained remission for concomitant AID was 29% at 3 years. Among 30 patients given allogeneic SCTx 19 developed graft-versus-host disease (GVHD) and 11 did not. Upon clinically justified discontinuation of all immunosuppressive therapy, 3111 patients without GVHD relapsed with their concomitant AID (freedom of AID-relapse 69% at 9 years), whereas none of 19 patients with GVHD did so (log rank: P = 0.0135). Freedom of AID-relapse was superior after allo SCTx compared to autologous SCTx (89% at 18 years vs 38% at 5 years; log rank: P = 0.0002). Our data suggest that a graft-versus-autoimmunity effect after allogeneic hemopoietic SCTx mediates elimination of autoimmunity.