Structural and Functional Insights on an Uncharacterized Aγ-Globin-Gene Polymorphism Present in Four β0-Thalassemia Families with High Fetal Hemoglobin Levels.

Introduction: Several DNA polymorphisms have been associated with high production of fetal hemoglobin (HbF), although the molecular basis is not completely understood. In order to identify and characterize novel HbF-associated elements, we focused on five probands and their four families (from Egypt, Iraq and Iran) with thalassemia major (either β(0)-IVSII-1 or β(0)-IVSI-1) and unusual HbF elevation (>98 %), congenital or acquired after rejection of bone marrow transplantation, suggesting an anticipated favorable genetic background to high HbF expression.

Methods: Patient recruitment, genomic DNA sequencing, western blotting, electrophoretic mobility shift assays, surface plasmon resonance (SPR) biospecific interaction analysis, bioinformatics analyses based on docking experiments.

Mixed chimerism evolution is associated with T regulatory type 1 (Tr1) cells in a β-thalassemic patient after haploidentical haematopoietic stem cell transplantation.

In a cohort of β-Thalassemia (β-Thal) transplanted with haploidentical-HSCT we identified one transplanted patient characterized by persistent mixed chimerism (PMC) for several months after HSCT. In this unique β-Thal patient we assessed the donor engraftment overtime after transplantation, the potential loss of the non-shared HLA haplotype, and the presence of CD49b(+)LAG-3(+) T regulatory type 1 (Tr1) cells, previously demonstrated to be associated with PMC after HLA-related HSCT for β-Thal. The majority of the patient's erythrocytes were of donor origin, whereas T cells were initially mostly derived from the recipient, no HLA loss, but an increased frequency of circulating Tr1 cells were observed.

Optimal Outcomes in Young Class 3 Patients With Thalassemia Undergoing HLA-Identical Sibling Bone Marrow Transplantation.

Background: Bone marrow transplantation (BMT) for class 3 patients with thalassemia is challenging due to high rates of graft rejection and transplant-related mortality. Since the first studies of BMT in the late 1980s, a number of conditioning regimens have been designed to improve outcomes, but with suboptimal results. Here we report the outcome of transplantation in class 3 patients using a modified protocol.

Haematopoietic stem cell transplantation in Nigerian sickle cell anaemia children patients.

Background: Sickle cell anaemia (SCA) remains associated with high risks of morbidity and early death. Children with SCA are at high risk for ischaemic stroke and transient ischaemic attacks, secondary to intracranial arteriopathy involving carotid and cerebral arteries. Allogeneic haematopoietic stem cell transplantation (HSCT) is the only curative treatment for SCA.

Invasive pulmonary aspergillosis in a haematopoietic stem cell transplant recipient with sickle cell disease: a successful treatment.

Sickle Cell Anaemia (SCA) is the most common inherited blood disorder and is associated with severe morbidity and decreased survival. Allogeneic Haematopoietic Stem Cell Transplantation (HSCT) is the only curative approach. Nevertheless the decision to perform a bone marrow transplant includes the risk of major complications and transplant-related mortality.

New insights into the pharmacokinetics of intravenous busulfan in children with sickle cell anemia undergoing bone marrow transplantation.

Background: Busulfan (Bu) is an integral part of conditioning regimens for patients with sickle cell anemia (SCA) undergoing transplantation. Patients with SCA might predispose to transplant-related neurological and pulmonary toxicities due to pre-existing disease-related cerebrovascular and lung injury. Bu therapy appears to be an important contributing factor in this context.

Peripheral red blood cell split chimerism as a consequence of intramedullary selective apoptosis of recipient red blood cells in a case of sickle cell disease.

Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia.

Transfusion-independent β(0)-thalassemia after bone marrow transplantation failure: proposed involvement of high parental HbF and an epigenetic mechanism.

Currently, bone marrow transplantation is the only curative treatment for β-thalassemia and sickle cell disease. In rare cases, sustained and full fetal hemoglobin production was observed in patients after failure of bone marrow transplantation. This rendered the patients transfusion-free, despite genetic disease and transplant rejection.

BAT2 and BAT3 polymorphisms as novel genetic risk factors for rejection after HLA-related SCT.

The genetic background of donor and recipient is an important factor determining the outcome of allogeneic hematopoietic SCT (allo-HSCT). We applied whole-genome analysis to investigate genetic variants-other than HLA class I and II-associated with negative outcome after HLA-identical sibling allo-HSCT in a cohort of 110 β-Thalassemic patients. We identified two single-nucleotide polymorphisms (SNPs) in BAT2 (A/G) and BAT3 (T/C) genes, SNP rs11538264 and SNP rs10484558, both located in the HLA class III region, in strong linkage disequilibrium between each other (R(2)=0.

Reduction of intramedullary apoptosis after stem cell transplantation in black african variant of pediatric sickle cell anemia.

Background And Purpose: Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for sickle cell anemia (SCA). We report our experience with transplantation in children with the Black African variant of SCA and the effects of transplant on erythroid compartment in bone marrow (BM).

Patients And Methods: Twenty-seven consecutive patients who underwent BM transplantation from HLA-identical donors following a myeloablative conditioning regimen were included.

Bone marrow transplantation for thalassemia from alternative related donors: improved outcomes with a new approach.

Bone marrow transplantation (BMT) performance can be limited by a lack of ideal donors, and the role of alternative donor hematopoietic cell transplantation in thalassemia is not well established. Here we used a new treatment protocol (Pc 26.1) in 16 thalassemia patients to perform BMT using phenotypically HLA-identical or 1-antigen-mismatched relatives (related donors [RDs]).

Long-term health-related quality of life evaluated more than 20 years after hematopoietic stem cell transplantation for thalassemia.

The principal aim of our study was to investigate whether patients transplanted more than 20 years ago for β-thalassemia major had a different health-related quality of life (HRQoL) compared with the general population. The Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT) were received from 109 ex-thalassemia patients who underwent hematopoietic stem cell transplantation (HSCT) during the 1980s and 1990s. Adjusted comparisons were performed separately for patient age at HSCT and the presence or absence of graft-versus-host disease (GVHD).

Optimization of the immunomagnetic selection in microcythemic donors enrolled for haploidentical transplantation.

Background: Immunomagnetic cell selection (ICS) cells is increasingly used in allogeneic hematopoietic transplantation in order to reduce the T cells quantity. The aim of this study was to evaluate an protocol based on Ficoll method before ICS.

Study Design And Methods: The automated procedure was compared with the standard method.

Hematopoietic stem cell transplantation in thalassemia and sickle cell anemia.

The globally widespread single-gene disorders β-thalassemia and sickle cell anemia (SCA) can only be cured by allogeneic hematopoietic stem cell transplantation (HSCT). HSCT treatment of thalassemia has substantially improved over the last two decades, with advancements in preventive strategies, control of transplant-related complications, and preparative regimens. A risk class-based transplantation approach results in disease-free survival probabilities of 90%, 84%, and 78% for class 1, 2, and 3 thalassemia patients, respectively.

Cell processing for haplo-identical hematopoietic stem cell transplantation: automated washing and immunomagnetic-positive selection.

Background Aims: Immunomagnetic cell selection (ICS) of CD34(+) cells is being used increasingly in allogeneic transplantation in order to reduce T-cell quantity. The aim of this study was to evaluate an automated washing protocol before immunomagnetic selection.

Methods: The automated method was compared with a conventional washing procedure.

Split chimerism between nucleated and red blood cells after bone marrow transplantation for haemoglobinopathies.

Previous studies have shown that a stable presence of both donor and recipient haematopoietic derived cells after allogeneic haematopoietic stem cell transplantation (HSCT) occurs in approximately ten percent of the patients affected by β-Thalassemia. Once achieved this condition, defined as persistent mixed chimerism (PMC), the patients do not require additional red blood cells (RBCs) support and, regardless of the presence in some cases of an extremely low percentage of donor-derived nucleated cells, they are clinically cured by an incomplete, but functional graft. Most of the published papers have, however, investigated the impact of donor engraftment in the nucleated cells rather than in the mature erythrocytes.

Hematopoietic stem cell transplantation for thalassemia.

Hematopoietic stem cell transplantation (HSCT) represents the only cure for patients with thalassemia. At present HSCT in younger patients from an HLA- matched sibling donor offers 80% to 87% probability of cure according to risk classes. However, results HSCT in adult patients continue to be inferior due to advanced of disease.

Allogeneic cellular gene therapy for hemoglobinopathies.

Hematopoietic stem cell transplantation (HSCT) offers potentially curative therapy for patients with thalassemia major and sickle cell disease (SCD). Current myeloablative treatment protocols allow the cure of 78% to 90% of patients with thalassemia and 72% to 96% with SCD, depending on disease status at the time of transplantation. The major limitation to successful transplantation is the lack of a suitable HLA-matched family donor.

Quantitatively different red cell/nucleated cell chimerism in patients with long-term, persistent hematopoietic mixed chimerism after bone marrow transplantation for thalassemia major or sickle cell disease.

Background: Persistent mixed chimerism represents a state in which recipient and donor cells stably co-exist after hematopoietic stem cell transplantation. However, since in most of the studies reported in literature the engraftment state was observed in the nucleated cells, in this study we determined the donor origin of the mature erythrocytes of patients with persistent mixed chimerism after transplantation for hemoglobinopathies. Results were compared with the engraftment state observed in singly picked out burst-forming unit - erythroid colonies and in the nucleated cells collected from the peripheral blood and from the bone marrow.

Progress in hematopoietic stem cell transplantation as allogeneic cellular gene therapy in thalassemia.

Allogeneic hemopoietic stem cell transplantation (HSCT) represents one of the best cures for thalassemia. Currently, HSCT for thalassemia consists of allogeneic stem cell gene therapy and still awaits autologous genetically modified stem cell transplantation. HSCT for thalassemia has substantially improved over the last two decades, due in large part to improvements in preventive strategies, the effective control of transplant-related complications, and the development of new preparative regimens.

Correction of beta-thalassemia major by gene transfer in haematopoietic progenitors of pediatric patients.

Beta-thalassemia is a common monogenic disorder due to mutations in the beta-globin gene and gene therapy, based on autologous transplantation of genetically corrected haematopoietic stem cells (HSCs), holds the promise to treat patients lacking a compatible bone marrow (BM) donor. We recently showed correction of murine beta-thalassemia by gene transfer in HSCs with the GLOBE lentiviral vector (LV), expressing a transcriptionally regulated human beta-globin gene. Here, we report successful correction of thalassemia major in human cells, by studying a large cohort of pediatric patients of diverse ethnic origin, carriers of different mutations and all candidates to BM transplantation.

Immunohematologic reconstitution in pediatric patients after T cell-depleted HLA-haploidentical stem cell transplantation for thalassemia.

To analyze immunohematologic reconstitution, particularly of natural killer (NK) cells, we evaluated 13 β-thalassemia patients after 20 and 60 days and 1 year posttransplantation with T cell-depleted HLA-haploidentical stem cells. We assessed lymphocyte and bone marrow (BM) progenitor cell phenotype and differentiation capacity, spontaneous BM cytokine production, stromal cells, and stromal cell interleukin (IL)-7 production. A reduced clonogenic capability manifested at day +20.