Globin gene transfer as a potential treatment for the beta-thalassaemias and sickle cell disease

AbstractThe human ζ-globin gene (HBZ) is transcribed in primitive erythroid cells only during the embryonic stages of development. Reactivation of this embryonic globin synthesis would likely alleviate symptoms both in α-thalassemia and sickle-cell disease. However, the molecular mechanisms controlling ζ-globin expression have remained largely undefined. Moreover, the pharmacologic agent capable of inducing ζ-globin production is currently unavailable. Here, we show that TRIAC, a bioactive thyroid hormone metabolite, significantly induced ζ-globin gene expression during zebrafish embryogenesis. The induction of ζ-globin expression by TRIAC was also observed in human K562 erythroleukemia cell line and primary erythroid cells. Thyroid hormone receptor α (THRA) deficiency abolished the ζ-globin-inducing effect of TRIAC. Furthermore, THRA could directly bind to the distal enhancer regulatory element to regulate ζ-globin expression. Our study provides the first evidence that TRIAC acts as a potent inducer of ζ-globin expression, which might serve as a new potential therapeutic option for patients with severe α-thalassemia or sickle-cell disease.

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Sickle Cell Disease: Role of Oxidative Stress and Antioxidant Therapy

Antioxidants ◽

10.3390/antiox10020296 ◽

2021 ◽

Vol 10 (2) ◽

pp. 296

Author(s):

Rosa Vona ◽

Nadia Maria Sposi ◽

Lorenza Mattia ◽

Lucrezia Gambardella ◽

Elisabetta Straface ◽

...

Keyword(s):

Oxidative Stress ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Globin Gene ◽

Organ Damage ◽

Cell Disease ◽

Vessel Occlusion ◽

Antioxidant Agents ◽

Oxidant Status

Sickle cell disease (SCD) is the most common hereditary disorder of hemoglobin (Hb), which affects approximately a million people worldwide. It is characterized by a single nucleotide substitution in the β-globin gene, leading to the production of abnormal sickle hemoglobin (HbS) with multi-system consequences. HbS polymerization is the primary event in SCD. Repeated polymerization and depolymerization of Hb causes oxidative stress that plays a key role in the pathophysiology of hemolysis, vessel occlusion and the following organ damage in sickle cell patients. For this reason, reactive oxidizing species and the (end)-products of their oxidative reactions have been proposed as markers of both tissue pro-oxidant status and disease severity. Although more studies are needed to clarify their role, antioxidant agents have been shown to be effective in reducing pathological consequences of the disease by preventing oxidative damage in SCD, i.e., by decreasing the oxidant formation or repairing the induced damage. An improved understanding of oxidative stress will lead to targeted antioxidant therapies that should prevent or delay the development of organ complications in this patient population.

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Hypoxia-induced acute lung injury in murine models of sickle cell disease

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00288.2002 ◽

2004 ◽

Vol 286 (4) ◽

pp. L705-L714 ◽

Cited By ~ 57

Author(s):

Kirkwood A. Pritchard ◽

Jingsong Ou ◽

Zhijun Ou ◽

Yang Shi ◽

James P. Franciosi ◽

...

Keyword(s):

Sickle Cell Disease ◽

Lung Injury ◽

Sickle Cell ◽

Globin Gene ◽

Heat Shock Protein 90 ◽

Cell Disease ◽

Vascular Congestion ◽

Nitrite Nitrate ◽

Endothelial Nitric Oxide

Vaso-occlusive events are the major source of morbidity and mortality in sickle cell disease (SCD); however, the pathogenic mechanisms driving these events remain unclear. Using hypoxia to induce pulmonary injury, we investigated mechanisms by which sickle hemoglobin increases susceptibility to lung injury in a murine model of SCD, where mice either exclusively express the human α/sickle β-globin (hαβS) transgene (SCD mice) or are heterozygous for the normal murine β-globin gene and express the hαβStransgene (mβ+/-, hαβS+/-; heterozygote SCD mice). Under normoxia, lungs from the SCD mice contained higher levels of xanthine oxidase (XO), nitrotyrosine, and cGMP than controls (C57BL/6 mice). Hypoxia increased XO and nitrotyrosine and decreased cGMP content in the lungs of all mice. After hypoxia, vascular congestion was increased in lungs with a greater content of XO and nitrotyrosine. Under normoxia, the association of heat shock protein 90 (HSP90) with endothelial nitric oxide synthase (eNOS) in lungs of SCD and heterozygote SCD mice was decreased compared with the levels of association in lungs of controls. Hypoxia further decreased association of HSP90 with eNOS in lungs of SCD and heterozygote SCD mice, but not in the control lungs. Pretreatment of rat pulmonary microvascular endothelial cells in vitro with xanthine/XO decreased A-23187-stimulated nitrite + nitrate production and HSP90 interactions with eNOS. These data support the hypotheses that hypoxia increases XO release from ischemic tissues and that the local increase in XO-induced oxidative stress can then inhibit HSP90 interactions with eNOS, decreasing ·NO generation and predisposing the lung to vaso-occlusion.

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Sickle Cell Disease Hematopoietic Stem Cell gene therapy with globin gene addition is promising

10.31219/osf.io/j5fkb ◽

2021 ◽

Author(s):

Moataz Dowaidar

Keyword(s):

Gene Therapy ◽

Stem Cell ◽

Sickle Cell Disease ◽

Hematopoietic Stem Cell ◽

Sickle Cell ◽

Globin Gene ◽

Autologous Transplantation ◽

Gene Repair ◽

Cell Disease ◽

Hematopoietic Stem

Autologous transplantation of gene-modified HSCs might be used to treat Sickle Cell Disease (SCD) once and for all. Hematopoietic Stem Cell (HSC) gene therapy with lentiviral-globin gene addition was optimized by HSC collection, vector constructs, lentiviral transduction, and conditioning in the current gene therapy experiment for SCD, resulting in higher gene marking and phenotypic correction. Further advancements over the next decade should allow for a widely approved gene-addition therapy. Long-term engraftment is crucial for gene-corrected CD34+ HSCs, which might be addressed in the coming years, and gene repair of the SCD mutation in the-globin gene can be achieved in vitro using genome editing in CD34+ cells. Because of breakthroughs in efficacy, safety, and delivery strategies, in vivo gene addition and gene correction in BM HSCs is advancing. Overall, further research is needed, but HSC-targeted gene addition/gene editing therapy is a promising SCD therapy with curative potential that might be widely available soon.

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Prevalence of Sickle Cell Disease and Other Haemoglobin Variants in Calabar, Cross River State, Nigeria

Annual Research & Review in Biology ◽

10.9734/arrb/2019/v33i530132 ◽

2019 ◽

pp. 1-6

Author(s):

Akaba Kingsley ◽

Ofem Enang ◽

Ofonime Essien ◽

Annette Legogie ◽

Omini Cletus ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Genetic Disorder ◽

Globin Gene ◽

Specific Gene ◽

Cell Disease ◽

Cellulose Acetate Electrophoresis ◽

Genetic Changes ◽

Female Ratio ◽

Cross River State

Background: Sickle cell disease (SCD) is the commonest genetic disorder worldwide with a global prevalence of 20-25 million. About 12-15 million affected persons are in Sub-Sahara Africa with Nigeria bearing the highest burden of people living with sickle cell disease. SCD is a disease characterized as an autosomal, recessive, heterogeneous, and a monogenetic disorder caused by an A-to-T point mutation in the β-globin gene responsible for the production of abnormal hemoglobin S (HbS), which polymerizes in the deoxygenated state and results in the sickling of erythrocytes. Haemoglobin variants are mutant forms of haemoglobin in a population usually occurring as a result of genetic changes in specific genes, or globins that causes change on alterations in the amino acid. They could affect the structure, behavior, the production rate and the stability of the specific gene. Well-known haemoglobin variants such as sick-cell anaemia are responsible for diseases and are considered haemoglobinopathies. Other variants cause no detectable pathology and are thus considered as non-pathological variants. Aim: The study is aimed at evaluating the burden of sickle cell disease and other haemoglobin variants in Calabar, South-South Nigeria. Methods: This is a retrospective study done at the haematology laboratory of University of Calabar Teaching Hospital, Calabar. Cellulose acetate electrophoresis at alkaline pH was used for the evaluation of haemoglobinopathies. The data were entered into Microsoft Excel 2016 spreadsheet and analysed with the IBM SPSS Version 22. Data were summarized into percentage of different phenotypes. Results: Results of the total 3648 haemoglobin electrophoresis recorded, 1368 (37.50%) were male while the remaining 2280 (62.5%) females given a male to female ratio of 1:1.7. Five haemoglobin phenotypes were identified as HbAA, HbAS, HbAC, HbSC and HbSS. The overall average values of their prevalence were HbAA 64.78%, HbAS 32.62%, HbSS 2.14%, HbAC 0.33%, HbSC 0.14%. Thus, the prevalence of SCD (Prevalence of HbSS+HbSC) was 2.28%. The highest proportion of SCD was observed in 2011 with least in 2016 and 2017 respectively. Conclusion: The prevalence of SCD and other haemoglobin variants in Calabar is similar to that of the national prevalence rate. There is need for continuous enlightenment and premarital counselling on the pattern of inheritance of SCD most especially with the increased burden of sickle traits in the environment has reported in this study.

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