Humoral immune response to Comirnaty (BNT162b2) SARS-Cov2 mRNA vaccine in Thalassemia Major patients.

One of the most urgent needs worldwide is to vaccinate against SARS-CoV-2 as many people as possible. We evaluated humoral response to Comirnaty vaccine in Thalassemia Major patients (TM). We measured SARS-CoV-2-specific antibodies against Spike protein in 57 TM patients and 58 healthy blood donors (HBD). TM and HBD subjects revealed a homogeneous serological response to the Comirnaty (Mean ± SD; TM = 1917,21 ± 1384,49; HBD = 2039,81 ± 1064,44; p = 0,5884). No statistically significant differences were observed among two groups. Interestingly, we observed in 73.3% of asplenic patients Ab-S titres above 800 BAU, whereas only in 26% of non splenectomized patients showed Ab-S titres above 800 BAU). This differences were statistically significant p < 0.039. Further measurement on other Ab types was needed for better understanding humoral response to Comirnaty.

Thalassaemia is paradoxically associated with a reduced risk of in-hospital complications and mortality in COVID-19: Data from an international registry.

Although numerous patient-specific co-factors have been shown to be associated with worse outcomes in COVID-19, the prognostic value of thalassaemic syndromes in COVID-19 patients remains poorly understood. We studied the outcomes of 137 COVID-19 patients with a history of transfusion-dependent thalassaemia (TDT) and transfusion independent thalassaemia (TIT) extracted from a large international cohort and compared them with the outcomes from a matched cohort of COVID-19 patients with no history of thalassaemia. The mean age of thalassaemia patients included in our study was 41 ± 16 years (48.9% male). Almost 81% of these patients suffered from TDT requiring blood transfusions on a regular basis. 38.7% of patients were blood group O. Cardiac iron overload was documented in 6.8% of study patients, whereas liver iron overload was documented in 35% of study patients. 40% of thalassaemia patients had a history of splenectomy. 27.7% of study patients required hospitalization due to COVID-19 infection. Amongst the hospitalized patients, one patient died (0.7%) and one patient required intubation. Continuous positive airway pressure (CPAP) was required in almost 5% of study patients. After adjustment for age-, sex- and other known risk factors (cardiac disease, kidney disease and pulmonary disease), the rate of in-hospital complications (supplemental oxygen use, admission to an intensive care unit for CPAP therapy or intubation) and all-cause mortality was significantly lower in the thalassaemia group compared to the matched cohort with no history of thalassaemia. Amongst thalassaemia patients in general, the TIT group exhibited a higher rate of hospitalization compared to the TDT group (p = 0.001). In addition, the rate of complications such as acute kidney injury and need for supplemental oxygen was significantly higher in the TIT group compared to the TDT group. In the multivariable logistic regression analysis, age and history of heart or kidney disease were all found to be independent risk factors for increased in-hospital, all-cause mortality, whereas the presence of thalassaemia (either TDT or TIT) was found to be independently associated with reduced all-cause mortality. The presence of thalassaemia in COVID-19 patients was independently associated with lower in-hospital, all-cause mortality and few in-hospital complications in our study. The pathophysiology of this is unclear and needs to be studied in vitro and in animal models.

COVID-19 pneumonia and pulmonary microembolism in a patient with B-thalassemia major.

We think that thalassemia is not necessarily a cause of aggravation of the clinical course in COVID-19; however, certain key factors must be considered, such as the anemic condition, the likely pathogenic role of the virus on hemoglobin, and the hypercoagulable state to prevent any complications.

One single bone marrow harvesting from donors under 3 years of age: assessing safety and efficacy of the procedure.

To candidate children as bone marrow donors raises two main concerns: donor safety and adequate marrow cell dose. Data in the field are limited and guidelines for child donor care management are lacking. In this context, we herein report the experience collected in our center by comparing very-young donors (defined as age ≤ 3 years) with young donors (defined as age > 3 years) who donated bone marrow (BM) for patients affected by beta-globin disorders.

Haploidentical HSCT for hemoglobinopathies: improved outcomes with TCRαß+/CD19+-depleted grafts.

We examined outcomes of haploidentical hematopoietic cell transplantation (haplo-HCT) using T-cell receptor αß+ (TCRαß+)/CD19+-depleted grafts (TCR group, 14 patients) in children with hemoglobinopathies. Patients received a preparative regimen consisting of busulfan, thiotepa, cyclophosphamide, and antithymocyte globulin preceded by fludarabine, hydroxyurea, and azathioprine. The median follow-up among surviving patients was 3.9 years. The 5-year probabilities of overall survival (OS) and disease-free survival (DFS) were 84% and 69%, respectively. The incidence of graft failure was 14%. We compared outcomes to a historical group of 40 patients with hemoglobinopathies who received CD34+-selected grafts (CD34 group). The median follow-up of surviving patients for the CD34 group was 7.5 years. The 5-year probabilities of OS and DFS were 78% and 39%, respectively. The CD34 group had a significantly higher incidence of graft failure (45%) than the TCR group (14%) (P = .048). The incidences of grades 2 to 4 acute graft-versus-host disease (GVHD) in the TCR and CD34 groups were 28% and 29%, respectively, and 21% and 10% (P = .1), respectively, for extensive chronic GVHD. Viral reactivation was common in both groups. The overall incidence of posttransplant lymphoproliferative disorders for the entire group was 16%. Among all patients, 5 developed autoimmune hemolytic anemia or thrombocytopenia, with the overall cumulative incidence of 11%. The 2 groups showed suboptimal CD4+ recovery within the first 6 months of transplantation with no significant difference between groups. These data demonstrate that TCRαß+/CD19+-depleted grafts are associated with a reduced incidence of graft failure, but delayed immune reconstitution and associated morbidity and mortality remain a significant challenge.

Posterior Reversible Encephalopathy Syndrome after Hematopoietic Cell Transplantation in Children with Hemoglobinopathies.

Posterior reversible encephalopathy syndrome (PRES) is a serious adverse event associated with calcineurin inhibitors used for graft-versus-host disease (GVHD) prophylaxis. We compared the incidence of PRES in children with thalassemia (n = 222, 1.4 to 17.8 years old) versus sickle cell disease (SCD; n = 59, 2 to 17 years old) who underwent hematopoietic cell transplantation from HLA-matched siblings or alternative donors and analyzed the risk factors for PRES. Overall, 31 children developed calcineurin inhibitor-related PRES (11%), including 30 patients with seizures and 1 patient without seizures. PRES incidence was significantly higher in SCD patients (22%; 95% confidence interval [CI], 10% to 32%) than in thalassemia patients (8%; 95% CI, 5% to 12%;P = .002). In multivariate analysis, factors associated with PRES were hypertension (hazard ratio [HR], 5.87; 95% CI, 2.57 to 13.43; P = .0001), SCD (HR, 2.49; 95% CI, 1.25 to 4.99; P = .009), and acute GVHD (HR 2.27; 95% CI, 1.06 to 4.85; P= .031). In the entire cohort overall survival (OS) was significantly higher in patients without versus with PRES (90% versus 77%; P = .02). In a subgroup analysis that including matched sibling transplants, OS and disease-free survival (DFS) were similar in thalassemia patients without PRES (92% and 88%, respectively) and with PRES (82% and 73%, respectively), whereas SCD patients with PRES had significantly lower OS (67%) and DFS (67%) than patients without PRES (94% and 94%, respectively; P = .008). Thus, SCD patients had a significantly higher incidence of PRES than thalassemia patients, and hypertension and GVHD were the 2 main risk factors for PRES in patients with hemoglobinopathies. Although PRES did not significantly influence survival in patients with thalassemia, patients with SCD had significantly lower survival after PRES.

Structural and Functional Insights on an Uncharacterized Aγ-Globin-Gene Polymorphism Present in Four ß0-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 ß(0)-IVSII-1 or ß(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. RESULTS: A polymorphism of the Aγ-globin gene is here studied in four families with ß(0)-thalassemia (ß(0)-IVSII-1 and ß(0)-IVSI-1) and expressing unusual high HbF levels, congenital or acquired after rejection of bone marrow transplantation. This (G→A) polymorphism is present at position +25 of the Aγ-globin genes, corresponding to a 5'-UTR region of the Aγ-globin mRNA and, when present, is physically linked in chromosomes 11 of all the familiar members studied to the XmnI polymorphism and to the ß(0)-thalassemia mutations. The region corresponding to the +25(G→A) polymorphism of the Aγ-globin gene belongs to a sequence recognized by DNA-binding protein complexes, including LYAR (Ly-1 antibody reactive clone), a zinc-finger transcription factor previously proposed to be involved in down-regulation of the expression of γ-globin genes in erythroid cells. CONCLUSION: We found a novel polymorphism of the Aγ-globin gene in four families with ß(0)-thalassemia and high levels of HbF expression. Additionally, we report evidence suggesting that the Aγ-globin gene +25(G→A) polymorphism decreases the efficiency of the interaction between this sequence and specific DNA binding protein complexes.

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. METHODS: Sixty-three patients between 5 and 16.7 years of age with class 3 thalassemia received HLA-matched sibling BMT following either the original protocol (26 patients) or the modified protocol (37 patients). Both regimens comprised preconditioning cytoreduction with hydroxyurea and azathioprine starting at -45 days pretransplant, and fludarabine from days -16 to -12. Conditioning was performed with busulfan and cyclophosphamide (original protocol) or with busulfan, thiotepa, and cyclophosphamide (modified protocol). RESULTS: The 2 groups showed similar patient demographics. At day 0, the degree of cytoreduction (lymphopenia, neuthropenia, and thrombocytopenia) achieved by the modified protocol was greater than the original protocol. The incidence of graft failure/rejection was significantly higher in the original group (15%; 95% confidence interval [95% CI], 5-32%) compared with the modified group (0%) (P = 0.014). The respective 5-year thalassemia-free survival rates were 73% (95% CI, 51-86%) and 92% (95% CI, 77-97%) (P = 0.047). Both groups showed similar incidences of grades II to IV acute graft-versus host disease. Modified protocol did not increase nonhematological toxicity or infectious complications. CONCLUSIONS: The modified treatment protocol effectively and safely prevented graft failure/rejection and significantly increased thalassemia-free survival of class 3 patients with thalassemia.

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. We report our experience with transplantation in a group of patients with the Black African variant of SCA. PATIENTS AND METHODS: This study included 31 consecutive SCA patients who underwent bone marrow transplantation from human leukocyte antigen (HLA)-identical sibling donors between 2010 and 2014 following a myeloablative-conditioning regimen. RESULTS: The median patient age was 10 years (range 2-17 years). Before transplantation, 14 patients had recurrent, painful, vaso-occlusive crisis; ten patients had recurrent painful crisis in association with acute chest syndrome; three patients experienced ischaemic stroke and recurrent vaso-occlusive crisis; two patients experienced ischaemic stroke; one patient exhibited leukocytosis; and one patient exhibited priapism. Of the 31 patients, 28 survived without sickle cell disease, with Lansky/Karnofsky scores of 100. All surviving patients remained free of any SCA-related events after transplantation. CONCLUSION: The protocols used for the preparation to the transplant in thalassaemia are very effective also in the other severe haemoglobinopathy as in the sickle cell anaemia with 90% disease free survival. Today, if a SCA patient has a HLA identical family member, the cellular gene therapy through the transplantation of the allogeneic haemopoietic cell should be performed. Tomorrow, hopefully, the autologous genetically corrected stem cell will break down the wall of the immunological incompatibility.

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. PROCEDURE: We studied the pharmacokinetics of intravenous Bu and clinical outcomes of 36 children with SCA undergoing bone marrow transplantation. Most patients had pre-existing organ system damage. Busulfan was administered every 6 hr for 4 days with pharmacokinetic-guided dose adjustment to target a conservative area under the concentration versus time curve (AUC) range of 900-1,350 µMol*min. RESULTS: We found that the first-dose Bu clearance was significantly higher (P < 0.0005) than the subsequent daily clearance, which remained unchanged during the following days. After the first-dose, 69% of patients achieved the target range. We adapted a new dose-adjustment strategy targeting exposures to the lower end (900 µMol*min) of the AUC range after the first dose of Bu to avoid unnecessary dose increases on subsequent days due to differences in clearance. This strategy enabled most patients to maintain the AUC within therapeutic range following dose adjustments. CONCLUSIONS: Differences in Bu clearance after the first-dose and subsequent daily doses in patients with SCA should be considered for pharmacokinetic-guided dose adjustment. Conservative AUC range and targeting exposures to the lower end of the range after the first dose was associated with negligible toxicity, and high engraftment and sickle cell-free survival rates.

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. Infections represent the leading cause of death in SCA patients undergoing HSCT. Invasive Pulmonary Aspergillosis (IPA) is a devastating opportunistic infection and remains a significant cause of morbidity and mortality in HSCT recipients. Data regarding IPA in the setting of SCA are lacking. In the present report, we describe a patient with SCA, who developed IPA after allogeneic bone marrow transplant. The fungal infection was treated by systemic antifungal therapy in addition to surgery, despite mild chronic graft versus host disease (GVHD) and continuing immunosuppressive therapy. This case shows that IPA occurring in bone marrow recipients with SCA can be successfully treated.

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. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism.

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. Using both CD71 and FSC parameters, we obtained three erythroid populations: EryA-C. Ery A (CD71(high) FSC(high)) are basophilic; Ery B (CD71(high) FSC(low)) are late basophilic and polychromatic; and Ery C (CD71(low) FSC(low)) are orthochromatic erythroblasts and reticulocytes. To analyze the effect of transplantation on intramedullary apoptosis, we studied Fas (CD95+) and caspase-3 expression in erythroblast subpopulations. RESULTS: All patients experienced sustained engraftment, and all surviving patients remained free of SCA-related events after transplantation. The erythroid population showed expansion in the BM at baseline. After transplant, levels decreased, especially of Ery C, in parallel to reduced Fas expression and an initial caspase 3 increase in erythroid population, similar to reported later steps of "normal" erythroid maturation. CONCLUSIONS: The results suggest a good chance of cure for children with SCA, with an excellent survival rate. We also observed "normalization" of erythroid populations in parallel with a decreased intramedullary apoptosis rate, suggesting normal erythroid maturation in ex-SCA patients after HSCT.

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]). We compared these results with HLA-matched sibling (matched sibling donors [MSDs]) BMT in 66 patients. The entire RD group and 88% of MSD group had sustained engraftment. Rejection incidence was 0% in the RD and 12% (95% confidence interval [95% CI], 6%-21%) in MSD groups (P = .15), with respective thalassemia-free survival probabilities of 94% (95% CI, 63%-99%) and 82% (95% CI, 70%-89%) (P = .24). Transplant-related mortality was 6% (95% CI, 1%-26%) in the RD group and 8% (95% CI, 3%-16%) in the MSD group (P = .83). The intensified new protocol was not associated with increased nonhematologic toxicity. The present data show that the Pc 26.1 preparative regimen allows thalassemia patients to safely undergo BMT from RDs who are not HLA-matched siblings, with transplant outcomes similar to patients with MSD grafts.

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 ß-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. Patients had significantly lower CD4(+) T cells versus controls, mainly in the CD45RA(+)CD62L(+) subset. NKs were among the first lymphocytes to repopulate the peripheral blood. At day +60, an increase in primitive BM progenitor cells paralleled small increases in CD4(+), naïve CD4(+), and thymic naïve Th cells. A significant increase in CD4(+) and CD8(+) markers paralleled an increase in CD3⁻CD16(+) NKs, especially with full engraftment. In patients with stable mixed chimerism we observed very low levels of CD3(+) donor chimerism early after transplant that increased over time, but a stable population of high donor NK cells, suggesting a role of these cells on donor engraftment. Stromal cells secreted less IL-7 and displayed "macrophage-like" morphology. Patients initially manifested impaired stem/progenitor cell growth and differentiation capacity in parallel with altered T cell homeostasis and a reduced T cell naïve compartment. We hypothesize that T cell compartment damage partly arises from altered new T cell production from the hematopoietic stem/progenitor cells under stromal cytokine influence. NNK subset analysis might be useful for determining transplant outcome.

Novel pharmacokinetic behavior of intravenous busulfan in children with thalassemia undergoing hematopoietic stem cell transplantation: a prospective evaluation of pharmacokinetic and pharmacodynamic profile with therapeutic drug monitoring.

We prospectively studied the pharmacokinetics (PK) and clinical outcomes of intravenous busulfan (Bu) in 71 children with preexisting liver damage who underwent hematopoietic stem cell transplantation for thalassemia. Intravenous Bu was administered every 6 hours as part of a conditioning regimen with PK-based dose adjustment to target a conservative area under the concentration-versus-time curve (AUC) range (900-1350 microMol*min). The first-dose Bu clearance (CL) was significantly higher than the subsequent daily CL that remained unchanged in the ensuing days. One-third of patients required dose escalation based on dose 1 AUC, whereas dose reduction was needed in the subsequent days. At doses 5, 9, and 13, 78%, 81%, and 87% of patients, respectively, achieved the target range of AUC. A population PK analysis confirmed that the first-dose CL was 20% higher and that body weight was the most important covariate to explain PK variability. Patients with variant GSTA1*B had a 10% lower Bu CL than wild-type. These results suggest that the disease-specific behavior of intravenous Bu PK should be considered for PK-guided dose adjustment in patients with thalassemia, and the use of a conservative AUC range resulted in low toxicity, good engraftment, and good survival rate.

Late-onset hemorrhagic cystitis in children after hematopoietic stem cell transplantation for thalassemia and sickle cell anemia: a prospective evaluation of polyoma (BK) virus infection and treatment with cidofovir.

Little is known about late-onset hemorrhagic cystitis (HC) in children, its relationship to BK virus, and treatment with cidofovir (CDV) following hematopoietic stem cell transplantation (HSCT). We prospectively investigated BK virus reactivation in children who underwent HSCT from a matched related donor for thalassemia or sickle cell anemia following busulfan-cyclophosphamide-based conditioning regimens and analyzed risk factors for development of HC and its treatment with CDV. Grade 2-4 HC occurred in 30 patients with a cumulative incidence of 26% (95% confidence interval [CI] = 18%-34%). The cumulative incidences of BK viruria and viremia were 81% (95% CI = 69%-89%) and 28% (95% CI = 18%-40%), respectively. Multivariate analysis revealed that use of antithymocyte globulin (ATG) (hazard ratio [HR] = 10.5; P = .001), peak BK viruria >100,000 copies/mL (HR = 6.2; P = .004), and grade II-IV acute graft-versus-host disease (HR = 5.3; P = .007) were predictive factors for HC. Nineteen patients with HC were given CDV at 1.5 mg/kg/day 3 times a week, or 5 mg/kg/week. The median duration of therapy was 27 days (range, 21-180 days), and a median of 9 doses were given (range, 6-22). All patients had a complete clinical response (CCR), and 69% had a microbiological response at 4 weeks. Eleven patients with BK virus-related HC receiving supportive care also had CCR. The median duration of HC in these patients was similar to that in patients treated with CDV. None of the patients with HC cleared BK viruria when CCR was achieved. We conclude that late-onset HC is more prevalent in children with sustained high BK viruria who are treated with ATG or who develop graft-versus-host disease. Randomized clinical trials are urgently needed to better define the role of CDV in treating BK virus-related HC.