Immune ablation and stem cell transplantation for severe Evans syndrome and refractory thrombocytopenic purpura

Successful HLA-identical hematopoietic stem cell transplantation in a patient with purine nucleoside phosphorylase deficiency

PNP deficiency is an autosomal recessive metabolic disorder characterized by severe combined immunodeficiency, autoimmune hemolytic anemia, and by a complex of neurologic manifestations including ataxia, developmental delay, and spasticity. PNP protein catalyzes the phosphorolysis of deoxyinosine and deoxyguanosine. It is found in most tissues of the body but is expressed at the highest levels in lymphoid tissues. This tissue distribution explains why the lymphoid system is predominantly affected in PNP deficiency. We describe a five-yr-old boy with muscular hypertonia, impaired growth, autoimmune hemolytic anemia, and neutropenia who underwent HSCT from his HLA-identical sister. One yr post-HSCT, the boy developed normal immunological functions, and his neurological status improved.

Successful unrelated cord blood transplantation in a 7-year-old boy with Evans syndrome refractory to immunosuppression and double autologous stem cell transplantation

Evans syndrome is an autoimmunopathy characterized by thrombocytopenia and autoimmune hemolytic anemia with poor response to immunosuppression. A 2-yr-old boy with Evans syndrome showed only short-lasting responses to immunosuppressive treatment including double autologous peripheral stem cell transplantation (SCT). Intracranial bleeding required emergency splenectomy and external ventricular drainage. Unrelated umbilical cord blood was given following conditioning with busulfan, thiotepa, etoposide and antithymocyte globulin. One year after SCT the patient shows stable blood counts without immunosuppression. This is the first child reported with Evans syndrome successfully treated by means of unrelated cord blood transplantation.

Development of common variable immunodeficiency in a patient with Evans syndrome treated by autologous stem cell transplantation

We describe a case report of a patient who developed common variable immunodeficiency (CVID) after autologous haematopoietic stem cell transplantation (SCT) for recurrent Evans syndrome. The disease manifested as attacks of haemolytic anaemia, thrombocytopenia and neutropenia from the age of 12 years. Presence of autoantibodies to blood elements was confirmed together with C4 deficiency. The patient also suffered from dermatitis herpetiformis Duhring without signs of coeliac disease. Autologous T cell-depleted peripheral blood stem cell (PBSC) transplant following conditioning regimen was performed at the age of 20 years. Immunological reconstitution was incomplete and 2 years after SCT he fulfilled laboratory criteria for common variable immunodeficiency (CVID). The patient was found to be a carrier of a risk haplotype for development of CVID DRB1*03/DQB1*0201. We conclude that T cell-depleted SCT here performed for autoimmune manifestations can hasten development of CVID in genetically predisposed patients.

Refractory Evans' syndrome treated with allogeneic SCT followed by DLI. Demonstration of a graft-versus-autoimmunity effect

Evans' syndrome, a combination of autoimmune haemolytic anaemia and autoimmune (idiopathic) thrombocytopenic purpura, is generally harder to treat and more refractory than the single entities. In a male patient with refractory disease, predominantly thrombocytopenic, an allogeneic reduced intensity BMT from his human leukocyte antigen (HLA)-identical sister was followed by a dramatic platelet peak while he was still experiencing initial engraftment (presumably of autologous origin), but subsequently by progressive relapse associated with mixed chimerism. Five gradually incremental DLI achieved complete donor chimerism, which was associated not only with grade II graft-versus-host disease (GVHD), but also with complete clinical and biological remission for 2 years post-transplant. Long-term FU is necessary before claiming that allogeneic stem cell transplantation (SCT) is capable of curing an autoimmune blood disease. However, there is evidence for a graft-versus-autoimmunity effect in this case.

Stem cell transplantation for autoimmune diseases

Much progress has been made in the field of haemopoietic stem cell transplants (HSCTs) for severe autoimmune disorders. Theoretical considerations, animal data and anecdotal evidence suggested some time ago that intensive immunoablation followed by autologous HSCT could restore normal immune reactivity in patients with severe autoimmune disorders. Based on a concept statement issued in 1995, two European societies, the European League Against Rheumatism (EULAR) and the European Group for Blood and Marrow Transplantation (EBMT) began collecting phase I/II trial data in an international collaborative network. Sufficient information from more than 350 patients allows a preliminary assessment with level three evidence. Autologous HSCTs can induce remissions in all disease categories tested so far. Remissions can be transient or durable. HSCTs are associated with significant morbidity and mortality. Treatment-related mortality (TRM) is near 10% at 1 year and is associated with the intensity of the conditioning and the stage of the disease at the time of transplant. Marked interdisease differences exist. There are few data available in haematological autoimmune diseases, more in systemic sclerosis (SSc), systemic lupus erythematosus (SLE), juvenile idiopathic arthritis (JIA) and multiple sclerosis (MS). Patient selection has been recognized as a crucial element from the phase I-II trials. Patients with advanced disease, severely compromised organ function or irreversible organ damage should not be considered as candidates for HSCT. Prospective randomized studies should now determine the value of HSCT compared to standard therapy. Such trials are ongoing for patients with systemic sclerosis (ASTIS trial--Autologous Stem Cell Transplantation International Scleroderma Trial) or are planned for patients with multiple sclerosis (ASTIMS trial--Autologous Stem Cell Transplantation International Multiple Sclerosis Trial) and rheumatoid arthritis (ASTIRA trial--Autologous Stem Cell Transplantation International Rheumatoid Arthritis Trial). More phase II data are needed for other indications such as SLE and JIA.

Intense immunosuppressive therapy followed by autologous peripheral blood selected progenitor cell reinfusion for severe autoimmune disease

Autologous stem cell transplantation (HSCT) has been shown to be effective in curing a large spectrum of autoimmune disorders. Case reports are being collected in the EBMT/EULAR Autoimmune Disease Stem Cell Project registry, which reports transplant-related mortality (TRM) of 6%. In order to reduce TRM and preserve the anti-autoimmune effect we evaluated a more immunoablative as opposed to myeloablative conditioning regimen for the autotransplant of severe immunomediated diseases. We enrolled patients affected by systemic lupus erythematosus (SLE: 3 patients), by autoimmune thrombocytopenic purpura (AITP: one patient), by thrombotic thrombocytopenic purpura (TTP: one patient), by pure red cell aplasia (PRCA: one patient), and by a severe cryoglobulinemia (one patient). All patients were mobilized with cyclophosphamide (Cy) 4 g/m2 + G-csf. Conditioning regimen consisted of Cy 50 mg/kg/day (days -6 and -5); anti-T-globulin (ATG) 10 mg/kg/day and 6-methylprednisolone (PDN) 1 g/day (days -4, -3, and -2). Immunomagnetically selected CD34+ cells were re-infused on day 0. In three patients neutrophil count fell below 0.5 x 10(9)/l, while a PLT count below 20 x 10(9)/l was registered in two patients. Extrahematological toxicity was very low. Four patients (2 SLE, 1 TTP, 1 cryoglobulinemia) are in complete corticosteroid-free remission with a median follow up of 335 days. The third SLE patient improved considerably; however, he still needs low-dose corticosteroid maintenance. The AITP and PRCA patients achieved a CR but soon relapsed; nevertheless, the procedure restored a steroid-sensitive status. The use of this immunoablative conditioning regimen in auto-HSCT transplant was shown to be effective in controlling disease progression and could be a valuable strategy in reducing TRM.

Autologous blood stem cell transplantation as therapy for autoimmune diseases

Autologous stem cell transplantation (ASCT) is starting to be investigated as a potential therapy for severe refractory autoimmune disease including rheumatological, neurological and haematological diagnoses. Increasing numbers of cases are now reported in the literature. Data from all transplanted patients are being collated in a centralized register by the European Group for Blood and Marrow Transplantation (EBMT) and the European League against Rheumatism (EULAR) to enable effective evaluation of the safety and efficacy of this promising technique. Thus far, results have been encouraging; however, more treatment-related deaths were reported in multiorgan diseases such as scleroderma and less in diseases such as rheumatoid arthritis, which confirms the importance of careful patient selection. Optimization of mobilization, conditioning regimen and graft manipulation is required to maximize efficacy without increasing mortality and morbidity. The use of maintenance therapy after ASCT in order to prevent relapse needs to be explored. Following individual case reports and small cohort studies, the next step is likely to involve multicentre randomized controlled trials.

New horizons in the treatment of autoimmune diseases: immunoablation and stem cell transplantation

The prevalence of autoimmune diseases (ADs) in Western countries is estimated to be from 3-7%, and the treatment of severe, relapsing/refractory cases is still not satisfactory. The concept of utilizing intense immunosuppression followed by allogeneic or even autologous hemolymphopoietic stem cells (HSCs) to treat AD is based on encouraging results in experimental animals and from serendipitous cases of patients with both ADs and malignancies who were allotransplanted for the latter. However, rare unexpected relapses despite donor immune engraftment have been reported following HSC transplantation for AD. Autologous transplantation is a more feasible procedure with lower toxicity than allogeneic transplantation. This article analyzes the experimental basis for stem cell transplantation in AD and discusses the most important clinical results of both allogeneic and autologous HSC transplants.