Alina Ferster

Gene Therapy for immunodeficiency due to Adenosine Deaminase Deficiency

BACKGROUND We investigated the long-term outcome of gene therapy for severe combined immunodeficiency (SCID) due to the lack of adenosine deaminase (ADA), a fatal disorder of purine metabolism and immunodeficiency. METHODS We infused autologous CD34+ bone marrow cells transduced with a retroviral vector containing the ADA gene into 10 children with SCID due to ADA deficiency who lacked an HLA-identical sibling donor, after nonmyeloablative conditioning with busulfan. Enzyme-replacement therapy was not given after infusion of the cells. RESULTS All patients are alive after a median follow-up of 4.0 years (range, 1.8 to 8.0). Transduced hematopoietic stem cells have stably engrafted and differentiated into myeloid cells containing ADA (mean range at 1 year in bone marrow lineages, 3.5 to 8.9%) and lymphoid cells (mean range in peripheral blood, 52.4 to 88.0%). Eight patients do not require enzyme-replacement therapy, their blood cells continue to express ADA, and they have no signs of defective detoxification of purine metabolites. Nine patients had immune reconstitution with increases in T-cell counts (median count at 3 years, 1.07x10(9) per liter) and normalization of T-cell function. In the five patients in whom intravenous immune globulin replacement was discontinued, antigen-specific antibody responses were elicited after exposure to vaccines or viral antigens. Effective protection against infections and improvement in physical development made a normal lifestyle possible. Serious adverse events included prolonged neutropenia (in two patients), hypertension (in one), central-venous-catheter-related infections (in two), Epstein-Barr virus reactivation (in one), and autoimmune hepatitis (in one). CONCLUSIONS Gene therapy, combined with reduced-intensity conditioning, is a safe and effective treatment for SCID in patients with ADA deficiency. (ClinicalTrials.gov numbers, NCT00598481 and NCT00599781.)

A treatment protocol for infants younger than 1 year with acute lymphoblastic leukaemia (Interfant-99): an observational study and a multicentre randomised trial

BACKGROUND Acute lymphoblastic leukaemia in infants younger than 1 year is rare, and infants with the disease have worse outcomes than do older children. We initiated an international study to investigate the effects of a new hybrid treatment protocol with elements designed to treat both acute lymphoblastic leukaemia and acute myeloid leukaemia, and to identify any prognostic factors for outcome in infants. We also did a randomised trial to establish the value of a late intensification course. METHODS Patients aged 0-12 months were enrolled by 17 study groups in 22 countries between 1999 and 2005. Eligible patients were stratified for risk according to their peripheral blood response to a 7-day prednisone prophase, and then given a hybrid regimen based on the standard protocol for acute lymphoblastic leukaemia, with some elements designed for treatment of acute myeloid leukaemia. Before the maintenance phase, a subset of patients in complete remission were randomly assigned to receive either standard treatment or a more intensive chemotherapy course with high-dose cytarabine and methotrexate. The primary outcomes were event-free survival (EFS) for the initial cohort of patients and disease-free survival (DFS) for the patients randomly assigned to a treatment group. Data were analysed on an intention-to-treat basis. This trial was registered with ClinicalTrials.gov, number NCT 00015873, and at controlled-trials.com, number ISRCTN24251487. FINDINGS In the 482 enrolled patients who underwent hybrid treatment, 260 (58%) were in complete remission at a median follow-up of 38 (range 1-78) months, and EFS at 4 years was 47.0% (SE 2.6, 95% CI 41.9-52.1). Of 445 patients in complete remission after 5 weeks of induction treatment, 191 were randomised: 95 patients to receive a late intensification course, and 96 to a control group. At a median follow-up of 42 (range 1-73) months, 60 patients in the treatment group and 57 controls were disease-free. DFS at 4 years did not differ between the two groups (60.9% [SE 5.2] for treatment group vs 57.0% [5.5] for controls; p=0.81). During the intensification phase, of 71 patients randomly assigned to the treatment group, and for whom toxicity data were available, 35 (49%) had infections, 21 (30%) patients had mucositis, 22 (31%) patients had toxic effects on the liver, and 2 (3%) had neurotoxicity. All types of rearrangements in the (mixed lineage leukaemia) MLL gene, very high white blood cell count, age of younger than 6 months, and a poor response to the prednisone prophase were independently associated with inferior outcomes. INTERPRETATION Patients treated with our hybrid protocol, and especially those who responded poorly to prednisone, had higher EFS than most reported outcomes for treatment of infant ALL. Delayed intensification of chemotherapy did not benefit patients.

CD81 gene defect in humans disrupts CD19 complex formation and leads to antibody deficiency.

Antibody deficiencies constitute the largest group of symptomatic primary immunodeficiency diseases. In several patients, mutations in CD19 have been found to underlie disease, demonstrating the critical role for the protein encoded by this gene in antibody responses; CD19 functions in a complex with CD21, CD81, and CD225 to signal with the B cell receptor upon antigen recognition. We report here a patient with severe nephropathy and profound hypogammaglobulinemia. The immunodeficiency was characterized by decreased memory B cell numbers, impaired specific antibody responses, and an absence of CD19 expression on B cells. The patient had normal CD19 alleles but carried a homozygous CD81 mutation resulting in a complete lack of CD81 expression on blood leukocytes. Retroviral transduction and glycosylation experiments on EBV-transformed B cells from the patient revealed that CD19 membrane expression critically depended on CD81. Similar to CD19-deficient patients, CD81-deficient patients had B cells that showed impaired activation upon stimulation via the B cell antigen receptor but no overt T cell subset or function defects. In this study, we present what we believe to be the first antibody deficiency syndrome caused by a mutation in the CD81 gene and consequent disruption of the CD19 complex on B cells. These findings may contribute to unraveling the genetic basis of antibody deficiency syndromes and the nonredundant functions of CD81 in humans.

Haematopoietic stem cell transplantation for sickle cell anaemia: the first 50 patients transplanted in Belgium

Fifty patients affected by sickle cell anaemia underwent transplantation of HLA-identical haematopoietic stem cells (bone marrow, 48; cord blood, 2). Two groups of patients were considered for transplantation. Group 1 included 36 permanent residents of a European country who, retrospectively, met the inclusion criteria accepted at a consensus conference held in Seattle in 1990, wherein children were selected because they already had evidence of a morbid course. Group 2 included 14 patients who were transplanted earlier, had not received more than three blood transfusions and were transplanted because they had decided to return to their country of origin. Kaplan–Meier estimates of overall survival, event-free survival and disease-free survival at 11 years of the whole grafted population are 93, 82 and 85%, respectively. In group 1, overall survival, EFS and DFS were 88, 76 and 80% and in group 2, 100, 93 and 93%, respectively. Clinical manifestations of the disease, as well as disease associated haemolytic anaemia, disappeared in all successfully treated patients. Recovery of spleen function was present in seven out of 10 evaluated patients. Adverse events (death, absence of engraftment, mixed chimerism and relapse) occurred more frequently in group 1 than in group 2 (25% vs 7%, P < 0.001). acute graft-versus-host disease (gvhd) was present in 20 patients (grade i or ii, 19; grade iii, 1), chronic gvhd in 10 (limited, 7; extensive, 3). one patient developed an acute myeloid leukaemia. gonadal dysfunction was present in all patients (six boys and eight girls) transplanted close to or after puberty, although transient in one adolescent girl.

Autologous stem cell transplantation for systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is responsive to treatment with immunosuppressives and steroids, but often pursues a relapsing or refractory course resulting in increasing incapacity and reduced survival. Autologous stem cell transplantation (ASCT) following immunoablative chemotherapy is a newer therapy for autoimmune disease of potential use in severe SLE. A retrospective registry survey was carried out by the European Blood and Marrow Transplant and European League Against Rheumatism (EBMT/EULAR) registry. Data was collected from 53 patients with SLE treated by ASCT in 23 centres. Disease duration before ASCT was 59 (2-155) months (median, range), 44 (83%) were female, and median age was 29 (9-52) years. At the time of ASCT a median of seven American College of Rheumatology (ACR) diagnostic criteria for SLE were present (range 2-10) and 33 (62%) had nephritis. Peripheral blood stem cells were mobilized with cyclophosphamide and granulocyte colony stimulating factor in 93% of cases. Ex vivo CD34 stem cell selection was performed in 42% of patients. Conditioning regimens employed cyclophosphamide in 84%, anti-thymocyte globulin in 76% and lymphoid irradiation in 22%. The mean duration of follow-up after ASCT was 26 (0-78) months. Remission of disease activity (SLEDAI < 3) was seen in 33/50 (66%; 95%CI 52-80) evaluable patients by six months, of which 10/31 (32%; 95%CI 15-50) subsequentlyrelapsed after six (3-40) months. Relapse was associated with negative anti-double stranded DNA (anti-dsDNA) antibodies before ASCT (P 0.007). There were 12 deaths after 1.5 (0-48) months, of which seven (12%; 95%CI 3-21) were related to the procedure. Mortality was associated with a longer disease course before ASCT (P 0.036). In conclusion, this registry study demonstrates the efficacy of ASCT for remission induction of refractory SLE, although mortality appeared high. The safety of this procedure is likely to be improved by patient selection and choice of conditioning regimen. The return of disease activity in one-third of patients might be reduced by long-term immunosuppressive therapy post-ASCT.

Long-term results of three randomized trials (58831, 58832, 58881) in childhood acute lymphoblastic leukemia: a CLCG-EORTC report. Children Leukemia Cooperative Group.

We present here the long-term results of three randomized clinical trials conducted on children with newly diagnosed acute lymphoblastic leukemia (ALL) between 1983 and 1998 by the Children Leukemia Cooperative Group (CLCG) from EORTC. In study 58831/32, the overall event-free survival (EFS) rates (± s.e.) at 6 and 10 years were 66% ± 1.8% and 65% ± 1.8%, respectively, and the risk of isolated central nervous system (CNS) relapse was 6% ± 1% and 7% ± 1%, respectively. In patients with a standard risk of relapse the omission of cyclophosphamide had no adverse effect on disease-free survival rates at 10 years (trial 58831). In medium- and high-risk patients the omission of radiotherapy did not increase the risk of CNS or systemic relapse (trial 58832). In study 58881 (1989–1998) the overall EFS rate at 8 years was 68.4% ± 1.2% and the risk of isolated CNS relapse was 4.2% ± 0.5%. In this trial which adressed three randomized questions, the following results were obtained: the combination of cytarabine at high doses with methotrexate at high doses during interval therapy did not improve prognosis. The addition of 6-mercaptopurine iv during maintenance increased the risk of late relapse. E. coli asparaginase was more toxic and has a higher efficacy than erwinia asparaginase. leukocyte counts >100 × 109/l, specific genetic abnormalities, a poor initial response to steroids or a high level of minimal residual disease at early time points were consistently associated with an adverse prognosis in the 58881 trial.

Human adenylate kinase 2 deficiency causes a profound hematopoietic defect associated with sensorineural deafness

Reticular dysgenesis is an autosomal recessive form of human severe combined immunodeficiency characterized by an early differentiation arrest in the myeloid lineage and impaired lymphoid maturation. In addition, affected newborns have bilateral sensorineural deafness. Here we identify biallelic mutations in AK2 (adenylate kinase 2) in seven individuals affected with reticular dysgenesis. These mutations result in absent or strongly decreased protein expression. We then demonstrate that restoration of AK2 expression in the bone marrow cells of individuals with reticular dysgenesis overcomes the neutrophil differentiation arrest, underlining its specific requirement in the development of a restricted set of hematopoietic lineages. Last, we establish that AK2 is specifically expressed in the stria vascularis region of the inner ear, which provides an explanation of the sensorineural deafness in these individuals. These results identify a previously unknown mechanism involved in regulation of hematopoietic cell differentiation and in one of the most severe human immunodeficiency syndromes.

Matched-related donor transplantation for sickle cell disease: report from the Center for International Blood and Transplant Research

We report outcomes after myeloablative haematopoietic cell transplantation (HCT) from human leucocyte antigen (HLA)‐matched sibling donors in 67 patients with sickle cell disease transplanted between 1989 and 2002. The most common indications for transplantation were stroke and recurrent vaso‐occlusive crisis in 38% and 37% of patients respectively. The median age at transplantation was 10 years and 67% of patients had received >10 red blood cell transfusions before HCT. Twenty‐seven percent of patients had a poor performance score at transplantation. Ninety‐four percent received busulfan and cyclophosphamide‐containing conditioning regimens and bone marrow was the predominant source of donor cells. Most patients achieved haematopoietic recovery and no deaths occurred during the early post‐transplant period. Rates of acute and chronic graft‐versus‐host disease were 10% and 22% respectively. Sixty‐four of 67 patients are alive with 5‐year probabilities of disease‐free and overall survival of 85% and 97% respectively. Nine patients had graft failure with recovery of sickle erythropoiesis, eight of who had recurrent sickle‐related events. This report confirms and extends earlier reports that HCT from HLA‐matched related donors offers a very high survival rate, with few transplant‐related complications and the elimination of sickle‐related complications in the majority of patients who undergo this therapy.

Live birth after autograft of ovarian tissue cryopreserved during childhood

Ovarian insufficiency is a major long-term adverse event, following the administration of a myeloablative conditioning regimen, and occurring in >80% of children and adolescents receiving such treatment for malignant or non-malignant disease. Cryopreservation of ovarian tissue is currently offered to preserve the fertility of these young patients. At least 35 live births have been reported after transplantation of cryopreserved ovarian tissue in adult patients, but the procedure remains unproven for ovarian tissue harvested at a prepubertal or pubertal age. We report here the first live birth after autograft of cryopreserved ovarian tissue in a woman with primary ovarian failure after a myeloablative conditioning regimen as part of a hematopoietic stem cell transplantation performed for homozygous sickle-cell anemia at age 14 years. This first report of successful fertility restoration after the graft of ovarian tissue cryopreserved before menarche offers reassuring evidence for the feasibility of the procedure when performed during childhood.

FAS-L, IL-10, and double-negative CD4- CD8- TCR alpha/beta+ T cells are reliable markers of autoimmune lymphoproliferative syndrome (ALPS) associated with FAS loss of function.

Autoimmune lymphoproliferative syndrome (ALPS) is characterized by splenomegaly, lymphadenopathy, hypergammaglobulinemia, accumulation of double-negative TCRalphabeta(+) CD4(-)CD8(-) T cells (DNT cells), and autoimmunity. Previously, DNT cell detection and a functional defect of T cells in a FAS-induced apoptosis test in vitro had been used for ALPS diagnosis. However, a functional defect can also be detected in mutation-positive relatives (MPRs) who remain free of any ALPS-related disease. In contrast, lymphocytes from patients carrying a somatic mutation of FAS exhibit normal sensitivity to FAS-induced apoptosis in vitro. We assessed the soluble FAS-L concentration in the plasma of ALPS patients carrying FAS mutations. Overall, we showed that determination of the FAS-L represents, together with the IL-10 concentration and the DNT cell percentage, a reliable tool for the diagnosis of ALPS.