Stem cell transplantation for primary immunodeficiencies

Indication for allogeneic stem cell transplantation in Glanzmann’s thrombasthenia

Glanzmann’s thrombasthenia (GT) is an autosomal recessive disorder characterized by a lack of thrombocyte aggregation due to the absence of thrombocyte glycoproteins IIb and αIIbβ3. The role of haematopoietic stem cell transplantation (HSCT) in GT remains controversial. However, HSCT offers the only curative approach for patients with a severe clinical phenotype.

In this review, we will discuss the limitation of current status evidence and the specific risk of GT, in particular the alloimmunization and refractoriness to thrombocyte infusions. 19 successful HSCT in 18 GT type I patients have been reported. Mean age at transplantation was 5 years. All patients are still alive. The majority received sibling bone marrow transplant with busulfan and cyclophosphamid conditioning. GvHD incidence was within the normal range, but 10 patients showed alloimmunization of thrombocytes. Median follow up is 25 months.

Longitudinal Evaluation of Immune Reconstitution and B-cell Function After Hematopoietic Cell Transplantation for Primary Immunodeficiency

PURPOSE

Hematopoietic cell transplantation (HCT) provides a curative therapy for severe forms of primary immunodeficiencies (PID). While the timing and extent of T-cell reconstitution following transplant for PID has been studied in depth, less is known about the kinetics of B-cell development and long-term restoration of humoral functions, which been often reported to be suboptimal after HCT.

METHODS

We studied longitudinally B-cell development and function in a cohort of 13 PID patients transplanted between 1997 and 2010, with a follow-up ranging from 0.7 to 15 years. Flow cytometric analysis of naïve and antigen-experienced B-cell subsets and in vitro functional responses to CpG were compared with data from healthy children and correlated with the degree of B-cell chimerism and in vivo antibody production.

RESULTS

We found that total memory B-cells count remained below normal levels for the first 2 years of follow up and progressively normalized. Switched memory B-cells (CD19+CD27+IgD-IgM-) were restored early and better than IgM memory B-cells (CD19+CD27+IgD+IgM+), which remained significantly reduced long-term. The recovery of memory B-cells correlated with good in vivo humoral function and normalization of CpG-response. A complete B-cell reconstitution was usually associated with donor B-cells chimerism and pre-transplant conditioning. Donor source and the underlying genetic defect represented also important variables.

CONCLUSION

Monitoring of phenotypic and functional changes on B-cells following HCT may prove clinically relevant to tailor patients' care. In particular the analysis of IgM memory and switched memory B-cells in addition to in vitro B-cells stimulation are recommended before Ig replacement therapy (IgRT) discontinuation.

Autoimmune complications after hematopoietic stem cell transplantation in children with nonmalignant disorders

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) remains the only curative treatment for many nonmalignant disorders, such as autoimmune disorders, inborn metabolic disorders, hemoglobinopathies, and immunodeficiency disorders. Autoimmune complications (AICs) after HSCT, such as autoimmune cytopenias, autoimmune hepatitis, primary biliary cirrhosis, and autoimmune cutaneous manifestations, are still neither well defined nor characterized.

PATIENTS

Between 2000 and 2012, 92 patients (47 males, 45 females) were treated with HSCT in our hospital, 51 with congenital hemoglobinopathies, 19 with primary immunodeficiency disease, 10 with metabolic disorders, five with Fanconi anemia, three with aplastic anemia, and four with familial hemophagocytic lymphohistiocytosis.

RESULTS

Mean age at HSCT was 6.4 years (range, 0.2-32 years) and mean duration of followup after HSCT was 6.81 years (range, 1-11 years). Sixteen (17.4%) patients developed chronic GVHD and five (5.4%) showed sclerodermatous features. Five (5.4%) patients were diagnosed with scleroderma manifestations, six (6.5%) with vitiligo, six (6.5%) with autoimmune hemolytic anemia (AIHA), six (6.5%) with idiopathic thrombocytopenia, three (3.3%) with mild leucopenia, two (2.2%) with aplastic anemia, two (2.2%) (one boy, one girl) with autoimmune thyroid disease, and one (1.1%) with autoimmune hepatitis.

CONCLUSIONS

It was concluded that AICs are clinically significant complications after HSCT that contribute to morbidity but not to mortality. AICs are more frequent after HSCT for metabolic disorders, and sclerodermatous GVHD is more significant in children who underwent allogeneic HSCT for hemoglobinopathies. The potential to identify risk factors for AICs could lead to less morbidity and mortality and to maintain the patient's quality of life.

Possible primary immunodeficiency presenting with gastrointestinal symptoms: Case report and minireview

Primary immunodeficiency is a disease characterized by reduced levels of serum immunoglobulins and multiple clinical manifestations. Patients with primary immunodeficiency frequently present with gastrointestinal symptoms, such as diarrhea, malabsorption and weight loss. The mainstay of treatment is replacement therapy with intravenous immunoglobulin (IVIG). In the current study, we report the case of a 23-year-old man with symptoms of chronic diarrhea, malabsorption and weight loss that had been apparent for two years. Subsequent to being diagnosed with possible primary immunodeficiency, the patient was treated with 30 mg/day oral prednisone for one month. The prednisone was then tapered weekly by 5 mg until withdrawal. Three months later, the patient’s clinical symptoms disappeared and his quality of life improved. During the subsequent nine months follow-up, the patient was able to work without suffering any effects from his illness. The body weight of the patient increased and plasma albumin levels were normal. In conclusion, this study describes the case of a patient with primary immunodeficiency-related gastrointestinal symptoms who responded well to oral prednisone treatment.

Stem cell transplantation for primary immunodeficiency disease: experience of a singapore hospital

Abstract

We retrospectively analyzed the outcomes of hematopoietic stem cell transplantation in 7 patients with primary immunodeficiency diseases treated at the National University Hospital, Singapore, over the period from December 1996 to January 2010. The primary immunodeficiency diseases managed were X-linked hyperimmunoglobulin M syndrome (n = 3), severe combined immunodeficiency (n = 1), leukocyte adhesion deficiency type 1 (n = 1), chronic granulomatous disease (n = 1), and Wiskott–Aldrich syndrome (n = 1). The age of the patients ranged from 5 months to 17 years. Conditioning regimen depended on the type of immunodeficiency, whereas supportive treatment was tailored for differing pretransplant conditions. Eight stem cell transplantations were performed for 7 patients. Donors were HLA-matched sibling donors for 2 patients and unrelated donors for the rest. At the median follow-up of 8.6 years (range 2.2–15.0 years) as of December 2011, 6 patients were alive and cured of their primary diseases.

A single-center study of hematopoietic stem cell transplantation for primary immune deficiencies (PIDD)

PIDD are rare inherited disorders that can result in life-threatening infections. Allogeneic HSCT is the only cure for many primary immune deficiencies; however, the specific diseases and optimal type(s) of transplants are not clear. This study compares transplant outcomes in a large cohort with a relatively uniform pre- and post-transplant management strategies. We conducted a retrospective analysis of 39 pediatric patients who underwent HSCT for SCID (n = 25) or other immune deficiencies (n = 14) from 1986 to 2010. A structured case report form was used to collect clinical information. The outcomes of survival, immune reconstitution, engraftment, incidence of GvHD and IVIG dependency were tabulated. Overall survival rates were 88% for SCID and 86% for other primary immune deficiencies, which are high compared to other historical series. No single variable was associated with mortality. Immunoglobulin dependence occurred only in patients who had X-linked SCID and a parental donor haploidentical transplant. Because of improved supportive care and use of alternative donors and conditioning regimens, HSCT has become an acceptable option for an increasing number of PIDD subtypes not previously transplanted with high frequency. This study encourages greater use of transplantation.

Immunodeficiencies

Primary immunodeficiencies (PIDs) are uncommon, chronic and severe disorders of the immune system in which patients cannot mount a sufficiently protective immune response, leading to an increased susceptibility to infections. The treatment of choice for PID patients with predominant antibody deficiency is intravenous immunoglobulin (Ig) replacement therapy. Despite major advances over the last 20 years in the molecular characterization of PIDs, many patients remain undiagnosed or are diagnosed too late, with severe consequences. Various strategies to ensure timely diagnosis of PIDs are in place, and novel approaches are being developed. In recent years, several patient registries have been established. Such registries shed light on the pathology and natural history of these varied disorders. Analyses of the registry data may also reveal which patients are likely to respond well to higher Ig infusion rates and may help to determine the optimal dosing of Ig products. Faster infusion rates may lead to improved convenience for patients and thus increase patient compliance, and may reduce nursing time and the need for hospital resources. Data from two recent studies suggest that Gamunex and Privigen are well tolerated at high infusion rates. Nevertheless, careful selection of patients for high infusion rates, based on co-morbid conditions and tolerance of the current infusion rate, is advisable. Based on the available data, intravenous Ig offers broad protection against encapsulated organisms. As vaccine trends change, careful monitoring of specific antibody levels in the general population, such as those against pneumococcal and meningococcal bacteria, should be implemented.

Stem cells and the frontiers of neonatology

The aim of the most recent studies on regenerative medicine was to focus on capability of stem cells deriving not only from haematopoietic system, but also from other organ and tissues, to regenerate damaged tissues. Stem cells derived from foetal annexes such as cord blood, placenta and amniotic fluid can be currently used in the effort to treat prenatally diagnosed genetic diseases. Cells derived from cord blood have been used since 1988 as an alternative source to realize stem cell transplantation. Compared with bone marrow, cord blood has shown the advantages of quick availability, less risk of GHVD, together with higher compatibility rates, and less risk of infections. Mesenchymal stem cells (MSCs) are multi-potent stem cells able to differentiate into different lineages, including osteocytes, chondrocytes, and adipocytes. Because of their trafficking capacity to injured tissues, clinical trials have been started evaluating the use of MSCs in the treatment of metabolic diseases like Hurler syndrome and metachromatic leukodystrophy, or Osteogenesis Imperfecta. MSCs were initially identified in adult bone marrow (BM-MSC), but cells resembling BM-MSCs have also been found in other tissues, both adult (peripheral blood, synovial membrane) and foetal (peripheral blood, liver, spleen, placenta, umbilical cord, and amniotic membrane). BM-MSCs have been widely used in clinical applications, as for cell-based therapy of Osteogenesis Imperfecta and metabolic diseases. In addition, human multi-potent MSCs present in second-trimester amniotic fluids may be a good target for prenatal gene therapy because of their expandability, their ability to differentiate into multiple lineages and their high transduction efficiency.

Allogeneic haemopoietic stem cell transplantation in children: what alternative donor should we choose when no matched sibling is available?

Allogeneic haemopoietic stem cell transplantation has provided curative therapy for life-threatening malignant and non-malignant diseases in children for over 40 years. Only 25% of children in whom an allograft is indicated have the ideal option of a human leucocyte antigen-identical sibling donor. Substantial advances in the use of alternative donors (unrelated volunteer donors, haploidentical family donors and unrelated umbilical cord blood donors) now make it possible for almost all children to benefit from this life-saving treatment. Each donor choice is associated with distinct advantages and disadvantages, which have greater or lesser importance in different diseases. We review the current status of alternative donor transplantation for haematological malignancies, primary immunodeficiencies, inherited metabolic disorders and bone marrow failure syndromes and outline the current UK consensus donor selection algorithms for these disease groups.