Current status of beta-thalassemia and its treatment strategies

Cellular and epigenetic perspective of protein stability and its implications in the biological system

Protein stability is a fundamental prerequisite in both experimental and therapeutic applications. Current advancements in high throughput experimental techniques and functional ontology approaches have elucidated that impairment in the structure and stability of proteins is intricately associated with the cause and cure of several diseases. Therefore, it is paramount to deeply understand the physical and molecular confounding factors governing the stability of proteins. In this review article, we comprehensively investigated the evolution of protein stability, examining its emergence over time, its relationship with organizational aspects and the experimental methods used to understand it. Furthermore, we have also emphasized the role of Epigenetics and its interplay with post-translational modifications (PTMs) in regulating the stability of proteins.

The Discovery of Selective Protein Arginine Methyltransferase 5 Inhibitors in the Management of β-Thalassemia through Computational Methods

β-Thalassemia is an inherited genetic disorder associated with β-globin chain synthesis, which ultimately becomes anemia. Adenosine-2,3-dialdehyde, by inhibiting arginine methyl transferase 5 (PRMT5), can induce fetal hemoglobin (HbF) levels. Hence, the materialization of PRMT5 inhibitors is considered a promising therapy in the management of β-thalassemia. This study conducted a virtual screening of certain compounds similar to 5'-deoxy-5'methyladenosine (3XV) using the PubChem database. The top 10 compounds were chosen based on the best docking scores, while their interactions with the PRMT5 active site were analyzed. Further, the top two compounds demonstrating the lowest binding energy were subjected to drug-likeness analysis and pharmacokinetic property predictions, followed by molecular dynamics simulation studies. Based on the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) score and molecular interactions, (3R,4S)-2-(6-aminopurin-9-yl)-5-[(4-ethylcyclohexyl)sulfanylmethyl]oxolane-3,4-diol (TOP1) and 2-(6-Aminopurin-9-yl)-5-[(6-aminopurin-9-yl)methylsulfanylmethyl]oxolane-3,4-diol (TOP2) were identified as potential hit compounds, while TOP1 exhibited higher binding affinity and stabler binding capabilities than TOP2 during molecular dynamics simulation (MDS) analysis. Taken together, the outcomes of our study could aid researchers in identifying promising PRMT5 inhibitors. Moreover, further investigations through in vivo and in vitro experiments would unquestionably confirm that this compound could be employed as a therapeutic drug in the management of β-thalassemia.

Psychological challenges and quality of life in Pakistani parents of children living with thalassemia

PURPOSE

Children living with thalassemia experience psychological challenges, but despite significant psychosocial burdens, caregivers' psychological wellbeing and quality of life remain understudied, particularly in lower-and-middle-income countries.

DESIGN AND METHOD

The current study evaluated these relationships in 100 male and female Pakistani caregivers (23-45 years; 61% female) using Ryff's Psychological Well-Being Scale and the Singapore Caregiver Quality of Life Scale. Caregivers completed questionnaires during regularly scheduled clinic visits for their child.

RESULTS

We found that Pakistani caregivers in our sample generally had significantly lower (30-40 points) quality of life than a referent sample of caregivers of older adults (ps < 0.001). Self-acceptance and personal growth were consistently significant predictors across quality of life domains. Further, significant interactions were observed. Female caregivers with less self-acceptance had worse mental health and wellbeing and impact on daily life (p < .05). Male caregivers with less personal growth had worse physical health wellbeing (p < .05).

CONCLUSIONS

Our results demonstrate the importance of considering how distinct aspects of psychological wellbeing, rather than just the overall score, relate to the specific quality of life domains among male and female caregivers.

PRACTICE IMPLICATIONS

Pediatric nurses are at the frontline of service delivery for children and are in a prime position to observe caregivers who could be at high risk for psychological challenges. Given our findings, future clinical interventions should prioritize support services promoting personal growth and self-acceptance for Pakistani caregivers of children living with thalassemia.

The effect of red blood cell disorders on male fertility and reproductive health

Male infertility is defined as a failure to conceive after 12 months of unprotected intercourse owing to suspected male reproductive factors. Non-malignant red blood cell disorders are systemic conditions that have been associated with male infertility with varying severity and strength of evidence. Hereditary haemoglobinopathies and bone marrow failure syndromes have been associated with hypothalamic-pituitary-gonadal axis dysfunction, hypogonadism, and abnormal sperm parameters. Bone marrow transplantation is a potential cure for these conditions, but exposes patients to potentially gonadotoxic chemotherapy and/or radiation that could further impair fertility. Iron imbalance might also reduce male fertility. Thus, disorders of hereditary iron overload can cause iron deposition in tissues that might result in hypogonadism and impaired spermatogenesis, whereas severe iron deficiency can propagate anaemias that decrease gonadotropin release and sperm counts. Reproductive urologists should be included in the comprehensive care of patients with red blood cell disorders, especially when gonadotoxic treatments are being considered, to ensure fertility concerns are appropriately evaluated and managed.

Beta-Thalassemia in Adulthood Previously Suspected as Treatment-Resistant Iron Deficiency Anemia: A Case Report

Beta-thalassemia (β-thalassemia) is a hematologic genetic condition that causes microcytic anemia due to defective synthesis of the hemoglobin beta chain. As a hypochromic microcytic anemia that is commonly associated with symptoms such as fatigue and pallor when identified in adulthood, β-thalassemia may be commonly underdiagnosed or misdiagnosed as iron deficiency anemia. This study presents a case of a patient with β-thalassemia who was initially misdiagnosed with treatment-resistant iron deficiency anemia. Here, we present the case of a 66-year-old male of Mediterranean descent with a history of military service who presented with persistent fatigue. He had a past medical history of hypertension, diabetes mellitus type 2, sleep apnea, and iron deficiency anemia. Despite undergoing unnecessarily prolonged iron supplementation for suspected iron deficiency anemia, the patient's complete blood count and peripheral blood smear continued to identify hypochromic microcytic anemia. Ultimately, hemoglobin electrophoresis was performed, and mutations were identified in the hemoglobin beta chain consistent with β-thalassemia minor. Due to its rarity and wide variation in presentation, β-thalassemia may be frequently misdiagnosed. β-thalassemia is a spectrum of disorders ranging from β-thalassemia minor, which may be asymptomatic and incidentally discovered in adulthood, to β-thalassemia major, which may include bone marrow deformities from extramedullary hematopoiesis and require frequent blood transfusions to sustain life. Therefore, patients who present with symptoms of β-thalassemia minor may not be identified until later in life after undergoing decades of ineffective treatment. β-thalassemia is a multifactorial disease with a variety of clinical presentations that can easily be misdiagnosed as other types of anemia. This case highlights the importance of performing thorough laboratory testing and casting a wide net of differential diagnoses when evaluating patients with treatment-resistant anemia. This case calls for further research on the genetic contributions to β-thalassemia as well as improved ways to identify this disorder, particularly in patients who may not have a severe form that is easily diagnosed in early childhood.

Oxidative Stress and Antioxidant Status in Adult Patients with Transfusion-Dependent Thalassemia: Correlation with Demographic, Laboratory, and Clinical Biomarkers

Iron overload in beta transfusion-dependent thalassemia (β-TDT) may provoke oxidative stress and reduction of the antioxidant defenses, with serious consequences for the disease course and complications. The present study evaluated the oxidant/antioxidant status of β-TDT patients and its correlation with demographic, clinical, laboratory, and instrumental biomarkers. The OXY-adsorbent assay and the d-ROMs (Diacron, Grosseto, Italy) were evaluated in 58 β-TDT patients (mean age: 37.55 ± 7.83 years, 28 females) enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. Iron overload was quantified with R2* magnetic resonance imaging. Mean OXY was 323.75 ± 113.19 μmol HClO/mL and 39 (67.2%) patients showed a decreased OXY-Adsorbent level (<350 μmol HClO/mL), of whom 22 (37.9%) showed severely reduced levels. Mean d-ROMs was 305.12 ± 62.19 UA; 12 (20.7%) patients showed oxidative stress, and 4 (6.9%) elevated oxidative stress. OXY showed a significant negative correlation with global and segmental cardiac iron levels. D-ROMs levels significantly correlated with markers of cardiovascular risk (aging, glycemia, and N-terminal pro-B-type natriuretic peptide). Antioxidant depletion is frequent in β-TDT patients, where OXY might serve as additive biomarker to assess heart iron status, whereas the d-ROMs might be helpful to assess the cardiovascular risk burden.

Peripheral blood circular RNA circ-0008102 may serve as a novel clinical biomarker in beta-thalassemia patients

Circular RNA circ-0008102 has previously been found dysregulated in β-thalassemia (β-thal) in circRNAs microarray (GSE196682 and GSE241141). Our study is aimed at identifying whether circ-0008102 could be a novel biomarker in β-thal. The peripheral blood of pediatric β-thal patients with (n = 39) or without (n = 20) blood transfusion and healthy controls (n = 30) was selected. qRT-PCR, ROC curve analysis, Spearman correlation analysis, and FISH were used to analyze clinical value of circ-0008102. qRT-PCR confirmed that circ-0008102 expression in pediatric β-thal patients without blood transfusion was significantly higher. ROC curves analysis showed that the AUC of circ-0008102 for differentiating patients without blood transfusion from patients with blood transfusion and healthy controls with an AUC of 0.733 and 0.711. Furthermore, circ-0008102 expression was positively correlated with the levels of RBC, HbF, β-globin, and γ-globin mRNA, but was negatively corrected with the levels of HbA and Cr. circ-0008102 was mainly located in the cytoplasm. circ-0008102 could induce the activation of γ-globin and negatively regulate the expression of the five highest-ranking candidate miRNAs (miR-372-3p, miR-329-5p, miR-198, miR-152-5p, and miR-627-3p) in K562 cells.

CONCLUSION

We demonstrate that peripheral blood upregulated circ-0008102 may serve as a novel clinical biomarker for pediatric β-thal without blood transfusion.

WHAT IS KNOWN

• CircRNAs are known to be involved in various human diseases, and several circRNAs are regarded as a class of promising blood-based biomarkers for detection of β-thal. • CircRNAs exert biological functions by epigenetic modification and gene expression regulation, and dysregulated circRNAs in β-thal might be involved in the induction of HbF in β-thal.

WHAT IS NEW

• Peripheral blood circ-0008102 maybe serve as a novel clinical biomarker for detection of pediatric β-thal without blood transfusion. • Circ-0008102 participates in the pathogenesis of β-thal through regulating γ-globin expression, and negatively regulates the expression of miR-372-3p, miR-329-5p, miR-198, miR-152-5p and miR-627-3p.

The interactions between ineffective erythropoiesis and ferroptosis in β-thalassemia

In Guangxi, Hainan, and Fujian Province in southern China, β-thalassemia is a frequent monogenic hereditary disorder that is primarily defined by hemolytic anemia brought on by inefficient erythropoiesis. It has been found that ineffective erythropoiesis in β-thalassemia is closely associated with a high accumulation of Reactive oxygen species, a product of oxidative stress, in erythroid cells. During recent years, ferroptosis is an iron-dependent lipid peroxidation that involves abnormalities in lipid and iron metabolism as well as reactive oxygen species homeostasis. It is a recently identified kind of programmed cell death. β-thalassemia patients experience increased iron release from reticuloendothelial cells and intestinal absorption of iron, ultimately resulting in iron overload. Additionally, the secretion of Hepcidin is inhibited in these patients. What counts is both ineffective erythropoiesis and ferroptosis in β-thalassemia are intricately linked to the iron metabolism and Reactive oxygen species homeostasis. Consequently, to shed further light on the pathophysiology of β-thalassemia and propose fresh ideas for its therapy, this paper reviews ferroptosis, ineffective erythropoiesis, and the way they interact.

Prognostic Role of Multiparametric Cardiac Magnetic Resonance in Neo Transfusion-Dependent Thalassemia

BACKGROUND

We prospectively evaluated the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in non-transfusion-dependent β-thalassemia (β-NTDT) patients who started regular transfusions in late childhood/adulthood (neo β-TDT).

METHODS

We considered 180 patients (38.25 ± 11.24 years; 106 females). CMR was used to quantify cardiac iron overload, biventricular function, and atrial dimensions, and to detect left ventricular (LV) replacement fibrosis.

RESULTS

During a mean follow-up of 76.87 ± 41.60 months, 18 (10.0%) cardiovascular events were recorded: 2 heart failures, 13 arrhythmias (10 supraventricular), and 3 cases of pulmonary hypertension. Right ventricular (RV) end-diastolic volume index (EDVI), RV mass index (MI), LV replacement fibrosis, and right atrial (RA) area index emerged as significant univariate prognosticators of cardiovascular complications. The low number of events prevented us from performing a multivariable analysis including all univariable predictors simultaneously. Firstly, a multivariable analysis including the two RV size parameters (mass and volume) was carried out, and only the RV MI was proven to independently predict cardiovascular diseases. Then, a multivariable analysis, including RV MI, RA atrial area, and LV replacement fibrosis, was conducted. In this model, RV MI and LV replacement fibrosis emerged as independent predictors of cardiovascular outcomes (RV MI: hazard ratio (HR) = 1.18; LV replacement fibrosis: HR = 6.26).

CONCLUSIONS

Our results highlight the importance of CMR in cardiovascular risk stratification.

The Italian breakthrough in CRISPR trials for rare diseases: a focus on beta-thalassemia and sickle cell disease treatment

The development of gene therapy and the current advantageous method of clustered regularly interspaced short palindromic repeats (CRISPRs) has allowed the implementation of several clinical trials aimed at studying the possible efficacy of gene therapy for rare diseases. Rare diseases pose a global challenge, in that their collective impact on health systems is considerable, whereas their individually rare occurrence hinders research and development of efficient therapies. Despite the low prevalence of individual rare diseases, there are more than 7,000 defined rare diseases affecting 3.5–5.9% of the global population. Rare diseases are mostly chronic and approximately 80% are caused by genetic mutation with an early-life onset. In Italy, in 2021 were recorded more than 400,000 people with rare disease. Because of its location and history, Italy has an unfortunate statistic regarding the presence and prevalence of two rare genetic diseases, namely beta-thalassemia, of which there are about 90 million carriers worldwide, 400,000 of whom are actually affected, and sickle cell disease, with about 300 million carriers and 6.5 million people affected worldwide. Advancements in genomic studies allowed Italy to join clinical trials to study effective and resolving gene therapies for BT and SCD. This study reports on the impact of rare diseases in Italy, ongoing studies, and recent achievements in BT and SCD trials using the CRISPR method and remaining hurdles in the application of CRISPR technology to rare diseases, also taking a glimpse at the newest challenges and future opportunities in the genetic treatment for rare diseases.

Reticulocyte Antioxidant Enzymes mRNA Levels versus Reticulocyte Maturity Indices in Hereditary Spherocytosis, β-Thalassemia and Sickle Cell Disease

The antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and peroxiredoxin 2 (Prx2) are particularly important in erythroid cells. Reticulocytes and other erythroid precursors may adapt their biosynthetic mechanisms to cell defects or to changes in the bone marrow environment. Our aim was to perform a comparative study of the mRNA levels of CAT, GPX1, PRDX2 and SOD1 in reticulocytes from healthy individuals and from patients with hereditary spherocytosis (HS), sickle cell disease (SCD) and β-thalassemia (β-thal), and to study the association between their transcript levels and the reticulocyte maturity indices. In controls, the enzyme mRNA levels were significantly correlated with reticulocyte maturity indices for all genes except for SOD1. HS, SCD and β-thal patients showed younger reticulocytes, with higher transcript levels of all enzymes, although with different patterns. β-thal and HS showed similar reticulocyte maturity, with different enzyme mRNA levels; SCD and HS, with different reticulocyte maturity, presented similar enzyme mRNA levels. Our data suggest that the transcript profile for these antioxidant enzymes is not entirely related to reticulocyte maturity; it appears to also reflect adaptive mechanisms to abnormal erythropoiesis and/or to altered erythropoietic environments, leading to reticulocytes with distinct antioxidant potential according to each anemia.

First Report of Filipino β0-Thalassemia/β-Thalassemia in a Chinese Family

A pregnant woman living in Fujian Province, southeastern China, presented due to a risk of having a baby with β-thalassemia major, during her second pregnancy, since she and her husband were suspected as β-thalassemia carriers and their affected daughter was a transfusion-dependent patient. Using the common α-thalassemia and β-thalassemia genotypes test, the pregnant woman was diagnosed as a β-thalassemia carrier with βIVS-2 - 654 (C→T)/βN genotype and her daughter had a homozygosity for IVS - 2 - 654 (C→T) mutation, however, no abnormalities were detected in her husband. SMRT identified a Filipino β0-deletion in her husband, and MLPA also revealed an unknown deletion in the HBB gene. Electrophoresis showed approximately 350 bp of the PCR product, and the β-Filipino genotype presented novel fracture fragments ranging from 5,112,884 to 5,231,358 bp, and lacked a 118,475 bp fragment relative to the wild-type sequence. The daughter was therefore diagnosed with the βIVS-2 - 654 (C→T)/βFilipino genotype. Prenatal diagnosis with umbilical cord blood at 27th week of gestation showed heteroztgosity for IVS - 2 - 654 (C→T) mutation in the fetus and continued pregnancy was recommended. In conclusion, we identified the Filipino β0-deletion in a Chinese family, from Fujian area, for the first time, during prenatal screening.

CRISPR/Cas-based gene editing in therapeutic strategies for beta-thalassemia

Beta-thalassemia (β-thalassemia) is an autosomal recessive disorder caused by point mutations, insertions, and deletions in the HBB gene cluster, resulting in the underproduction of β-globin chains. The most severe type may demonstrate complications including massive hepatosplenomegaly, bone deformities, and severe growth retardation in children. Treatments for β-thalassemia include blood transfusion, splenectomy, and allogeneic hematopoietic stem cell transplantation (HSCT). However, long-term blood transfusions require regular iron removal therapy. For allogeneic HSCT, human lymphocyte antigen (HLA)-matched donors are rarely available, and acute graft-versus-host disease (GVHD) may occur after the transplantation. Thus, these conventional treatments are facing significant challenges. In recent years, with the advent and advancement of CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated protein 9) gene editing technology, precise genome editing has achieved encouraging successes in basic and clinical studies for treating various genetic disorders, including β-thalassemia. Target gene-edited autogeneic HSCT helps patients avoid graft rejection and GVHD, making it a promising curative therapy for transfusion-dependent β-thalassemia (TDT). In this review, we introduce the development and mechanisms of CRISPR/Cas9. Recent advances on feasible strategies of CRISPR/Cas9 targeting three globin genes (HBB, HBG, and HBA) and targeting cell selections for β-thalassemia therapy are highlighted. Current CRISPR-based clinical trials in the treatment of β-thalassemia are summarized, which are focused on γ-globin reactivation and fetal hemoglobin reproduction in hematopoietic stem cells. Lastly, the applications of other promising CRISPR-based technologies, such as base editing and prime editing, in treating β-thalassemia and the limitations of the CRISPR/Cas system in therapeutic applications are discussed.

Beta-thalassemia: is cure still a dream?

β-thalassemia is a monogenic disorder characterized by decreased hemoglobin production, resulting in chronic anemia. There are several factors affecting the clinical presentation of patients with β-thalassemia, and several complications such as iron overload or ineffective erythropoiesis have been linked to this disease. Until nowadays, several conservative therapies namely blood transfusions, iron chelation, and the FDA-approved drug Luspatercept have been adopted alongside other debatable permanent cures. Other clinical trials are being conducted to develop better and safer management techniques for these patients. This review will discuss the different treatment strategies of β-thalassemia including novel therapies, besides all possible curative therapies that are being developed for this disease.

Calcium channel blockers for preventing cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia

BACKGROUND

Beta-thalassaemia is an inherited blood disorder that reduces the production of haemoglobin. The most severe form requires recurrent blood transfusions, which can lead to iron overload. Cardiovascular dysfunction caused by iron overload is the leading cause of morbidity and mortality in people with transfusion-dependent beta-thalassaemia. Iron chelation therapy has reduced the severity of systemic iron overload, but removal of iron from the myocardium requires a very proactive preventive strategy. There is evidence that calcium channel blockers may reduce myocardial iron deposition. This is an update of a Cochrane Review first published in 2018.

OBJECTIVES

To assess the effects of calcium channel blockers plus standard iron chelation therapy, compared with standard iron chelation therapy (alone or with a placebo), on cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books, to 13 January 2022. We also searched ongoing trials databases and the reference lists of relevant articles and reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of calcium channel blockers combined with standard chelation therapy versus standard chelation therapy alone or combined with placebo in people with transfusion-dependent beta thalassaemia.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included six RCTs (five parallel-group trials and one cross-over trial) with 253 participants; there were 126 participants in the amlodipine arms and 127 in the control arms. The certainty of the evidence was low for most outcomes at 12 months; the evidence for liver iron concentration was of moderate certainty, and the evidence for adverse events was of very low certainty. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may have little or no effect on cardiac T2* values at 12 months (mean difference (MD) 1.30 ms, 95% confidence interval (CI) -0.53 to 3.14; 4 trials, 191 participants; low-certainty evidence) and left ventricular ejection fraction (LVEF) at 12 months (MD 0.81%, 95% CI -0.92% to 2.54%; 3 trials, 136 participants; low-certainty evidence). Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may reduce myocardial iron concentration (MIC) after 12 months (MD -0.27 mg/g, 95% CI -0.46 to -0.08; 3 trials, 138 participants; low-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on heart T2*, MIC, or LVEF after six months, but the evidence is very uncertain. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may increase liver T2* values after 12 months (MD 1.48 ms, 95% CI 0.27 to 2.69; 3 trials, 127 participants; low-certainty evidence), but may have little or no effect on serum ferritin at 12 months (MD 0.07 μg/mL, 95% CI -0.20 to 0.35; 4 trials, 187 participants; low-certainty evidence), and probably has little or no effect on liver iron concentration (LIC) after 12 months (MD -0.86 mg/g, 95% CI -4.39 to 2.66; 2 trials, 123 participants; moderate-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on serum ferritin, liver T2* values, or LIC after six months, but the evidence is very uncertain. The included trials did not report any serious adverse events at six or 12 months of intervention. The studies did report mild adverse effects such as oedema, dizziness, mild cutaneous allergy, joint swelling, and mild gastrointestinal symptoms. Amlodipine may be associated with a higher risk of oedema (risk ratio (RR) 5.54, 95% CI 1.24 to 24.76; 4 trials, 167 participants; very low-certainty evidence). We found no difference between the groups in the occurrence of other adverse events, but the evidence was very uncertain. No trials reported mortality, cardiac function assessments other than echocardiographic estimation of LVEF, electrocardiographic abnormalities, quality of life, compliance with treatment, or cost of interventions.

AUTHORS' CONCLUSIONS

The available evidence suggests that calcium channel blockers may reduce MIC and may increase liver T2* values in people with transfusion-dependent beta thalassaemia. Longer-term multicentre RCTs are needed to assess the efficacy and safety of calcium channel blockers for myocardial iron overload, especially in younger children. Future trials should also investigate the role of baseline MIC in the response to calcium channel blockers, and include a cost-effectiveness analysis.

Newborn Screening

The goal of newborn screening is to identify medical conditions that can cause significant morbidity and/or mortality if not treated early in life. Pediatricians often play a vital role in the initial disclosure of newborn screening results and coordination of confirmatory testing, treatment, and referral to specialty care. The goal of this article is to provide an overview of current newborn screening in the United States, focusing on the various disorders, their manifestations, the newborn screening process, the confirmatory testing, and treatments. Some practical considerations will be discussed as well.

Pediatric reference intervals of the hemoglobin fractions HbA2, HbF and HbA0 using high-performance liquid chromatography and capillary electrophoresis

INTRODUCTION

β-thalassemia is a common genetic disorder with an estimated prevalence of 80-90 million carriers worldwide. As elevated hemoglobin A2 (HbA2) is a primary feature of carriers, hemoglobin fraction analysis is a common technique used for initial screening. However, pediatric reference intervals (RIs) are scarce. Hence, the aim was to establish pediatric RIs of hemoglobin fractions using high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE).

METHODS

Samples were collected from assumed healthy children and adolescents of 1-18 years. Analyses were conducted using the Tosoh Automated Glycohemoglobin Analyzer HLC-723®G11 (Tosoh G11, HPLC) and the Capillarys 3 Octa (CE). Data were investigated for need of partitioning by both age (1-6 years vs. 6-18 years) and sex.

RESULTS

In total, 189 and 196 subjects were included in the statistical analysis of HPLC and CE, respectively. The 95% RI of HbA2 was 2.00-2.90% by HPLC and 2.2-3.0% by CE. Partitioning of data was not clinically relevant by HPLC. However, partitioning by age was suggested by CE.

CONCLUSION

RIs of hemoglobin fractions in individuals of 1-18 years using commercially available HPLC and CE equipment were reported. This is the first report of a pediatric RI of HbA2 using the Tosoh G11.

Current Status of β-Thalassemic Burden in India

Thalassemia is a major public health concern in India. The thalassemic burden in India is high, with an estimated 100,000 patients diagnosed with β-thalassemia syndrome. However, the exact number is unknown because of the absence of National Registries for patients. India alone contributes to approximately 25% of the global β-thalassemia burden. A possible option to control this burden is to endorse education and awareness programs, compulsory prenatal screening, and develop suitable facilities for genetic counseling, and availability of cost-effective diagnostic tests in India, especially in rural areas. In addition to the various clinical complications associated with thalassemia, lifelong intervention creates mental and physical trauma in patients and their relatives. Government and nongovernment organizations have initiated screening programs to prevent thalassemia. However, prenatal screening is not mandatory, and the reachability of screening programs in rural areas is yet to begin. This review article will discuss the progress in thalassemia research in India, including its prevalence, spectrum of β-thalassemia mutations, preventive and therapeutic measures, and awareness programs. More importantly, we will discuss the need and roadmap to strengthen prevention programs in India.

Localized immunomodulation technologies to enable cellular and organoid transplantation

Localized immunomodulation technologies are rapidly emerging as a new modality with the potential to revolutionize transplantation of cells and organs. In the past decade, cell-based immunomodulation therapies saw clinical success in the treatment of cancer and autoimmune diseases. In this review, we describe recent advances in engineering solutions for the development of localized immunomodulation techniques focusing on cellular and organoid transplantation. We begin by describing cell transplantation and highlighting notable clinical successes, particularly in the areas of stem cell therapy, chimeric antigen receptor (CAR)-T cell therapy, and islet transplantation. Next, we detail recent preclinical studies centered on genome editing and biomaterials to enhance localized immunomodulation. We close by discussing future opportunities to improve clinical and commercial success using these approaches to facilitate long-term immunomodulation technologies.

Effects of Ramadan Intermittent Fasting on the Severity of β-Thalassemia Major Patients

BACKGROUND

β-thalassemia major (β-TM) is an inherited autosomal recessive disorder manifested by the hemoglobin β chain synthesis alteration. It is a lifelong illness with a scope of a wide range of complications. Many kinds of literature evaluated the effect of Ramadan intermittent fasting (RIF) on different medical conditions. However, there are no precise guidelines regarding its effect on patients with β-TM.

METHODS

A retrospective cohort study was conducted on β-TM patients who visited the hereditary blood disorder center at Al Karama Teaching Hospital in Baghdad. Accordingly, six parameters were used to evaluate the effect of RIF on β-TM patients before, during, and after Ramadan. These parameters include hemoglobin level, frequency of transfusion, aspartate aminotransferase (AST) level, alanine aminotransferase (ALT) level, left ventricular ejection fraction % (EF%), and spleen size. All of these details, including the demographic characteristics of age, gender, history of splenectomy, and body mass index (BMI) were retrieved from the patient's medical records after confirming their fasting through one-to-one interviews. This study aimed to fill the gap and investigate the possible effect of RIF on the severity of β-TM.

RESULTS

A total of 184 β-TM patients were enrolled in this study. The mean duration of fasting was 25.2±2.18 days. More than half (110) of the patients were females (59.8%). Whereas, the mean age was 24.8±3.5 years. One-third of the patients (65) had a splenectomy (35.3%) and more than two-thirds had normal BMI. The initial parameters used to score the severity of β-TM were evaluated separately. As a result, the hemoglobin level remained steady without any statistical significance during the three months. In addition, the frequency of blood transfusion and the spleen size carried the same result. Although the lowest median and range of liver enzymes were recorded during Ramadan, they were statistically insignificant compared to pre and post-fasting. Moreover, the left ventricular EF% was insignificant regardless of the patient's history of heart disease.

CONCLUSION

This study revealed that RIF does not seem to affect the severity of β-TM if the patients proceed with fasting. However, further studies in more countries with a bigger sample size are recommended to confirm these findings.

An evaluation of deferiprone as twice-a-day tablets or in combination therapy for the treatment of transfusional iron overload in thalassemia syndromes

INTRODUCTION

Regular blood transfusions in patients with thalassemia syndromes can cause iron overload resulting in complications including cirrhosis, heart problems, or endocrine abnormalities. To prevent iron overload toxicity in these patients, three iron chelators are currently FDA-approved for use: deferoxamine, deferasirox, and deferiprone. In the United States, deferiprone has been approved for three times daily dosing since 2011 and has recently gained approval for twice-daily administration.

AREAS COVERED

A PubMed literature search was performed with the keywords 'deferiprone' and 'thalassemia.' Relevant original research studying deferiprone's effects on transfusional iron overload in patients with thalassemia syndromes was included. Exclusion criteria included case reports and review papers. Deferiprone is effective at reducing serum ferritin levels in patients with iron overload. Twice-daily administration provides a similar level of iron chelation as three times daily dosing with a comparable side effect profile and increased patient acceptability.

EXPERT OPINION

New studies are highlighting deferiprone's potential for combination therapy with either deferoxamine or deferasirox to improve iron chelation. Deferiprone's ability to significantly decrease cardiac and liver iron content can be utilized in other transfusion-dependent hematologic conditions, as evidenced by its recent approval for use in the United States for sickle cell disease or other anemias.

Identification of novel mutations in β-thalassemia patients in Maysan Governorate, Iraq

BACKGROUND

In homozygous β-thalassemia, the primary genetic modifiers affecting the clinical severity of β-thalassemia are genetic variants and the ability to reduce globin chain imbalance, thus resulting in a milder form of thalassemia. However, there are few reports on the molecular genetics of β-thalassemia in Iraq.

METHODS

We performed PCR and DNA sequencing on 40 Iraqi patients who were clinically suspected of having β-thalassemia.

RESULTS

The first genetic sequencing study was conducted in Maysan Governate, Iraq, using patients from various locations to identify novel mutations. There were five novel mutations: 294.T>C 12% (city center and Almajar district), 205. C>T 25% (city center, Alsalam, and Almashrah districts), 289.G>A 38% (Almaymuna and Gleat Salih districts), 49.T>C 32% (city center), and 624.C>A 32% (city center). These mutations were identified among β-thalassemia patients by two regions of HBB gene 696 bp and 861 bp.

CONCLUSIONS

The discovery of new genetic variants helps predict the severity of β-thalassemia disease. There are relatively few studies in molecular genetics of β-thalassemia in Iraq, and the new mutations reported here will provide valuable data for the prevention and control of β-thalassemia in Maysan Governate, Iraq. The results can lead to new genetic sequencing investigations for other Iraqi regions.

Glucose Homeostasis and Assessment of β-Cell Function by 3-hour Oral Glucose Tolerance (OGTT) in Patients with β-Thalassemia Major with Serum Ferritin below 1,000 ng/dL: Results from a Single ICET-A Centre

Aims

The primary aim of this study was to evaluate retrospectively the glucose homeostasis and surrogate indices of insulin sensitivity and resistance, during a 3-hour oral glucose tolerance test (OGTT), in β-thalassemia major patients (β-TM) with serum ferritin (SF) below 1,000 ng/mL.

Patients and methods

The retrospective cohort study evaluated the medical records of 24 β-TM patients from 2010 to 2022. At the year of study the mean age of patients was 31.0 ± 4.1 (20-37.11) years; 13 (54.1%) were females. The most commonly used iron chelator was deferoxamine (DFO: 75%), followed by deferiprone (DFP:12.5%) and deferasirox (DFX: 12.5%). Insulin sensitivity and resistance indices were derived from OGTT. A liver iron concentration (LIC) < 3 mg/g d.w. and a global heart T2* value > 20 ms were considered as conservative cut-off values for insignificant iron overload (IOL).

Results

The mean SF levels in the whole study cohort population at the age of evaluation was 549.6 ± 232.3 ng/mL. Based on the SF levels, two groups were identified: Group A (N = 14) < 500 ng/mL and Group B (N=10) 500-1,000 ng/mL. Normal glucose tolerance (NGT) during OGTT was observed in 4 patients of Group A (28.5 %) and in 5 patients of Group B (50%) (P: 0.29). The remaining 15/24 patients (62.5%) had glucose dysregulation (GD). The mean age at starting iron chelation therapy (ICT) and the mean SF peak in Group A versus Group B were significantly higher in group A. The GD was associated with significantly attenuated IGI (first phase of insulin response) and impaired oral disposition index (oDI). Hypogonadotropic hypogonadism (HH) was the most common associated endocrine complication in both groups of patients.

Conclusions

This study showed that efficient iron chelation monotherapy in patients with β-TM and SF < 1,000 ng/ml did not entirely prevent glucose metabolism disorders, abnormalities of insulin secretion and sensitivity, and development of acquired hypogonadism.

Congenital Disorders of Red Blood Cells

See Bonus NeoBriefs videos and downloadable teaching slides Understanding the physiologic process of red blood cell development in utero and subsequent erythropoiesis in the neonate is crucial as this determines red blood cell structure and therefore function, which is vital to neonatal health. Infants frequently experience anemia, and special consideration must be given to the evaluation of these infants to determine the correct etiology. Traditionally, anemia is conceptualized in terms of inadequate red blood cell production, increased red blood cell destruction, or whole blood loss. This framework translates well to inherited red blood cell defects, which include genetic abnormalities in bone marrow productivity or structure of the red blood cell membrane, enzymes, or hemoglobin. This article highlights fetal and neonatal erythropoiesis and the underlying etiologies of the inherited red blood cell disorders, as well as reviews the appropriate diagnostic evaluation and next steps in management. It is imperative that neonatal clinicians remain informed about these disorders to enable early recognition and treatment, and ultimately to improve outcomes in affected infants.

Molecular prevalence of HBB-associated hemoglobinopathy among reproductive-age adults and the prenatal diagnosis in Jiangxi Province, southern central China

Background and aims: Hemoglobinopathy associated with the HBB gene, with its two general subtypes as thalassemia and abnormal hemoglobin (Hb) variants, is one of the most prevalent hereditary Hb disorders worldwide. Herein we aimed to elucidate the prevalence of ß-thalassemia and abnormal hemoglobin variants and the prenatal diagnosis of the HBB gene in Jiangxi Province, southern central China.

Methods: Hematological indices and capillary Hb electrophoresis were conducted for 136,149 subjects who were admitted to Jiangxi Maternal and Child Health Hospital and requested for hemoglobinopathy investigation. Routine α- and ß-globin genotyping were performed by gap-polymerase chain reaction (Gap-PCR) and reverse dot-blot (RDB) hybridization for the 11,549 individuals suspected to be thalassemia carriers. For participants whose genotypes could not explain their hematological indices, further Sanger sequencing and Gap-PCR were conducted for the detection of rare or novel variants in related globin genes. Prenatal diagnosis was performed for 77 pregnant couples both carrying ß-thalassemia trait at appropriate gestational ages.

Results: Among the 11,549 subjects, 2,548 individuals were identified with HBB-associated hemoglobinopathy based on molecular analysis. A total of 2,358 subjects were identified as ß-thalassemia heterozygous carriers and nine cases were diagnosed as compound heterozygous ß-thalassemia. Additionally, 125 cases were detected with composite α- and ß-thalassemia and the remaining 56 individuals with abnormal Hb variants in the HBB. A total of 35 types of variants were identified in the HBB gene, including 26 types of ß-thalassemia and nine types of abnormal Hb variants. Four novel variants were firstly reported, including one variant in HBA2 and three variants in HBB. Overall, 77 prenatal samples underwent ß-thalassemia molecular diagnosis; 20 fetuses were identified with normal ß-thalassemia genotypes, 30 fetuses as ß-thalassemia heterozygotes, 11 as homozygotes, and 16 as compound heterozygotes in HBB.

Conclusion: We have demonstrated a relatively high prevalence rate at 1.872% of ß-hemoglobinopathies including common and rare ß-thalassemia as well as abnormal Hb variants among large child-bearing population in the Jiangxi area of southern central China for the first time. Our data presents that prenatal diagnosis is an effective way to prevent and control birth defects of ß-thalassemia.

New Entity-Thalassemic Endocrine Disease: Major Beta-Thalassemia and Endocrine Involvement

Beta-thalassemia (BTH), a recessively inherited haemoglobin (Hb) disorder, causes iron overload (IO), extra-medullary haematopoiesis and bone marrow expansion with major clinical impact. The main objective of this review is to address endocrine components (including aspects of reproductive health as fertility potential and pregnancy outcome) in major beta-thalassemia patients, a complex panel known as thalassemic endocrine disease (TED). We included English, full-text articles based on PubMed research (January 2017–June 2022). TED includes hypogonadism (hypoGn), anomalies of GH/IGF1 axes with growth retardation, hypothyroidism (hypoT), hypoparathyroidism (hypoPT), glucose profile anomalies, adrenal insufficiency, reduced bone mineral density (BMD), and deterioration of microarchitecture with increased fracture risk (FR). The prevalence of each ED varies with population, criteria of definition, etc. At least one out of every three to four children below the age of 12 y have one ED. ED correlates with ferritin and poor compliance to therapy, but not all studies agree. Up to 86% of the adult population is affected by an ED. Age is a positive linear predictor for ED. Low IGF1 is found in 95% of the population with GH deficiency (GHD), but also in 93.6% of persons without GHD. HypoT is mostly pituitary-related; it is not clinically manifested in the majority of cases, hence the importance of TSH/FT4 screening. HypoT is found at any age, with the prevalence varying between 8.3% and 30%. Non-compliance to chelation increases the risk of hypoT, yet not all studies confirmed the correlation with chelation history (reversible hypoT under chelation is reported). The pitfalls of TSH interpretation due to hypophyseal IO should be taken into consideration. HypoPT prevalence varies from 6.66% (below the age of 12) to a maximum of 40% (depending on the study). Serum ferritin might act as a stimulator of FGF23. Associated hypocalcaemia transitions from asymptomatic to severe manifestations. HypoPT is mostly found in association with growth retardation and hypoGn. TED-associated adrenal dysfunction is typically mild; an index of suspicion should be considered due to potential life-threatening complications. Periodic check-up by ACTH stimulation test is advised. Adrenal insufficiency/hypocortisolism status is the rarest ED (but some reported a prevalence of up to one third of patients). Significantly, many studies did not routinely perform a dynamic test. Atypical EM sites might be found in adrenals, mimicking an incidentaloma. Between 7.5–10% of children with major BTH have DM; screening starts by the age of 10, and ferritin correlated with glycaemia. Larger studies found DM in up to 34%of cases. Many studies do not take into consideration IGF, IGT, or do not routinely include OGTT. Glucose anomalies are time dependent. Emerging new markers represent promising alternatives, such as insulin secretion-sensitivity index-2. The pitfalls of glucose profile interpretation include the levels of HbA1c and the particular risk of gestational DM. Thalassemia bone disease (TBD) is related to hypoGn-related osteoporosis, renal function anomalies, DM, GHD, malnutrition, chronic hypoxia-induced calcium malabsorption, and transplant-associated protocols. Low BMD was identified in both paediatric and adult population; the prevalence of osteoporosis/TBD in major BTH patients varies; the highest rate is 40–72% depending on age, studied parameters, DXA evaluation and corrections, and screening thoracic–lumbar spine X-ray. Lower TBS and abnormal dynamics of bone turnover markers are reported. The largest cohorts on transfusion-dependent BTH identified the prevalence of hypoGn to be between 44.5% and 82%. Ferritin positively correlates with pubertal delay, and negatively with pituitary volume. Some authors appreciate hypoGn as the most frequent ED below the age of 15. Long-term untreated hypoGn induces a high cardiovascular risk and increased FR. Hormonal replacement therapy is necessary in addition to specific BTH therapy. Infertility underlines TED-related hormonal elements (primary and secondary hypoGn) and IO-induced gonadal toxicity. Males with BTH are at risk of infertility due to germ cell loss. IO induces an excessive amount of free radicals which impair the quality of sperm, iron being a local catalyser of ROS. Adequate chelation might improve fertility issues. Due to the advances in current therapies, the reproductive health of females with major BTH is improving; a low level of statistical significance reflects the pregnancy status in major BTH (limited data on spontaneous pregnancies and growing evidence of the induction of ovulation/assisted reproductive techniques). Pregnancy outcome also depends on TED approach, including factors such as DM control, adequate replacement of hypoT and hypoPT, and vitamin D supplementation for bone health. Asymptomatic TED elements such as subclinical hypothyroidism or IFG/IGT might become overt during pregnancy. Endocrine glands are particularly sensitive to iron deposits, hence TED includes a complicated puzzle of EDs which massively impacts on the overall picture, including the quality of life in major BTH. The BTH prognostic has registered progress in the last decades due to modern therapy, but the medical and social burden remains elevated. Genetic counselling represents a major step in approaching TH individuals, including as part of the pre-conception assessment. A multidisciplinary surveillance team is mandatory.

Membrane Lipids in the Thyroid Comparing to Those in Non-Endocrine Tissues Are Less Sensitive to Pro-Oxidative Effects of Fenton Reaction Substrates

Iron is an essential microelement for the proper functioning of many organs, among others it is required for thyroid hormone synthesis. However, its overload contributes to the increased formation of reactive oxygen species via Fenton chemistry (Fe2++H2O2→Fe3++˙OH + OH−), and it is potentially toxic. Individual organs/tissues are affected differently by excess iron. The excessive absorption of iron with subsequent deposition in various organs is associated with diseases such as hemochromatosis. Such an iron deposition also occurs in the thyroid gland where it can disturb thyroid hormone synthesis. In turn, melatonin is an effective antioxidant, which protects against oxidative damage. This study aims to check if lipid peroxidation resulting from oxidative damage to membrane lipids, is caused by Fenton reaction substrates, and if protective effects of melatonin differ between the thyroid and various non-endocrine porcine tissues (liver, kidney, brain cortex, spleen, and small intestine). To mimic the conditions of iron overload, Fe2+ was used in extremely high concentrations. Homogenates of individual tissues were incubated together with Fenton reaction substrates, i.e., FeSO4 (9.375, 18.75, 37.5, 75, 150, 300, 600, 1,200, 1,800, 2,100, 2,400, 3,000, 3,600, 4,200, and 4,800 µM)+H2O2 (5 mM), either without or with melatonin (5 mM). The concentration of malondialdehyde+4-hydroxyalkenals (MDA+4-HDA), as the LPO index, was evaluated by a spectrophotometrical method. Fenton reaction substrates increased concentrations of LPO products in all chosen tissues. However, in the thyroid, compared to non-endocrine tissues, the damaging effect was generally weaker, it was not observed for the two lowest concentrations of iron, and the LPO peak occurred with higher concentrations of iron. Melatonin reduced experimentally induced LPO in all examined tissues (without differences between them), and these protective effects did not depend on iron concentration. In conclusion, membrane lipids in the thyroid compared to those in non-endocrine tissues are less sensitive to pro-oxidative effects of Fenton reaction substrates, without differences regarding protective effects of melatonin.

Correction of Beta-Thalassemia IVS-II-654 Mutation in a Mouse Model Using Prime Editing

Prime editing was used to insert and correct various pathogenic mutations except for beta-thalassemia variants, which disrupt functional beta-globin and prevent hemoglobin assembly in erythrocytes. This study investigated the effect of gene correction using prime editor version 3 (PE3) in a mouse model with the human beta-thalassemia IVS-II-654 mutation (C > T). The T conversion generates a 5′ donor site at intron 2 of the beta-globin gene resulting in aberrant splicing of pre-mRNA, which affects beta-globin expression. We microinjected PE3 components (pegRNA, nick sgRNA, and PE2 mRNA) into the zygotes from IVS-II-654 mice to generate mutation-edited mice. Genome sequencing of the IVS-II-654 site showed that PE3 installed the correction (T > C), with an editing efficiency of 14.29%. Reverse transcription-PCR analysis showed that the PE3-induced conversion restored normal splicing of beta-globin mRNA. Subsequent comprehensive phenotypic analysis of thalassemia symptoms, including anemic hematological parameters, anisocytosis, splenomegaly, cardiac hypertrophy, extramedullary hematopoiesis, and iron overload, showed that the corrected IVS-II-654 mice had a normal phenotype identical to the wild type mice. Off-target analysis of pegRNA and nick sgRNA additionally showed the genomic safety of PE3. These results suggest that correction of beta-thalassemia mutation by PE3 may be a straightforward therapeutic strategy for this disease.

Conditioning Regimens in Patients with β-Thalassemia Who Underwent Hematopoietic Stem Cell Transplantation: A Scoping Review

The success of transplant procedures in patients with beta-thalassemia major (β-thalassemia) goes hand-in-hand with improvements in disease knowledge, better supportive care, discoveries in immunogenetics, increase in stem cell sources, and enhancement of conditioning regimens. The aim of this scoping review was to report the evolution of conditioning regimes for β-thalassemia hematopoietic stem cell transplantation. We performed a systematic search for all relevant articles published before July 2021, using the following Medical Subject Headings: "bone marrow transplantation", "stem cell transplantation", "allogeneic", "thalassemia", "β-thalassemia", and "thalassemia major". The final analysis included 52 studies, published between 1988 and 2021, out of 3877 records. The most common conditioning regimen was a combination of busulfan and cyclophosphamide, with successive dose adjustments or remodulation based on patient characteristics. Pre-transplant treatments, reductions in cyclophosphamide dosage, or the adoption of novel agents such as treosulphan all improved overall survival and thalassemia-free survival in transplant-related mortality high-risk patients. Conditioning regimes were modulated for those without a suitable fully matched sibling or unrelated donor, with encouraging results. Hematopoietic stem cell transplantation with haploidentical donors is currently available to virtually all patients with β-thalassemia. However, disparities in outcome are still present around the world. In developing and limited-resource countries, where most diagnoses are focused, transplants are not always available. Therefore, more efforts are needed to close this treatment gap.

Activated CD4 + T lymphocyte is a potential biomarker for acute graft-vs.-host disease after hematopoietic stem cell transplantation in children with transfusion-dependent β-thalassemia

BACKGROUND

Acute graft-vs.-host disease (aGVHD) is still one of the most common and life-threatening complications of allogeneic hematopoietic stem cell transplantation (HSCT). Whether or not the level of activated T lymphocytes rises before the onset of aGVHD is unknown. We explored the possibility of T lymphocytes as biomarkers for early prediction of aGVHD in children with transfusion-dependent β-thalassemia (TDTβ).

METHODS

We retrospectively analyzed the characteristics of T lymphocyte subsets before and 14 days after HSCT in children with TDTβ who developed aGVHD. Data from 95 children (Age ≤ 14 years) who underwent allogeneic HSCT from January 2020 to December 2021 were collected. Patients were divided into non-aGVHD group (n = 55) and aGVHD group (n = 40), and aGVHD group was divided into two subgroups: grade I aGVHD (n = 16) and grade II-IV aGVHD (n = 24). Receiver operating characteristic curve (ROC) analysis was performed to predict aGVHD.

RESULTS

Before preconditioning in non-aGVHD and aGVHD groups, there was no significant difference in all lymphocyte subsets and ratio of CD4 + /CD8 + T cells. On day 14 post-transplantation in non-aGVHD and aGVHD groups, the absolute concentrations per μl blood of T cells, CD4 + T cells, CD8 + T cells, activated CD4 + T cell and NK cells, were 69.73 (14.70, 137.77) and 140.36 (65.06, 293.42), 10.00 (2.35, 23.59) and 35.91 (12.41, 68.71), 37.25 (5.82, 84.36) and 89.99 (35.83, 180.81), 0.52 (0.17, 2.20) and 4.08 (0.91, 11.12), 43.86 (15.00, 91.31) and 26.35 (15.19, 49.39), respectively. On day + 14 (14 days post-transplantation), the differences in all cell subsets and the ratio of CD4 + /CD8 + T cells were not statistically significant between grade I aGVHD and grade II-IV aGVHD subgroups. The absolute concentrations of CD8 + T cells in grade I aGVHD were significantly higher than in grade II-IV aGVHD [128.21 (61.11, 258.91) vs. 60.81 (21.59, 176.38), P = 0.057]. AUC of NK cells, CD8 + T cells, T cells, CD4 + T cells, and CD4 + CD25 + T cells were 0.6275, 0.6839, 0.7068, 0.7241, and 0.7589, and cut-off values were 73.75 (97.50, 34.55), 146.90 (37.50, 94.55), 187.30 (45.00, 90.91), 18.95 (70.00, 72.73), and 3.24 (52.50, 87.27), respectively. The AUC of the combined CD4 + CD25 + T cells and CD8 + T cells, CD4 + CD25 + T cells and T cells, CD4 + CD25 + T cells and CD4 + T cells, CD4 + CD25 + T cells and NK cells, respectively, were 0.7500, 0.7598, 0.7750, and 0.8050.

CONCLUSION

Our findings demonstrate that level of activated CD4 + T cells on day + 14 (post-HSCT) is a valuable biomarker for predicting aGVHD in children with TDTβ and CD8 + T cells could likely be a biomarker for severe aGVHD.