scholarly journals Anti-GDF11Treatment of β-Thalassemia Intermedia Mice Does Not Improve Erythropoiesis

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 7-8
Author(s):  
Heinrich E Lob ◽  
Leah Kravets ◽  
Lawrence Miloscio ◽  
Jason Mastaitis ◽  
Aris N Economides ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Ex Vivo ◽  
Physiological Mechanism ◽  
Cell Number ◽  
Beta Thalassemia ◽  
Minor Role ◽  
Thalassemia Intermedia ◽  
Publicly Traded ◽  
Ineffective Erythropoiesis

Beta-thalassemia is a hereditary iron-independent anemia, caused by a reduction of β-globin, affecting millions of people globally. Current treatments such as blood transfusions and iron chelation show significant toxicities and add to organ damage. Luspatercept (Acvr2b(L79D)-Fc) is a novel treatment for transfusion-dependent β-thalassemia patients that improves erythropoiesis independent of erythropoietin. The exact mechanism of action remains unknown, and it is controversially discussed if growth differentiation factor 11 (GDF11) is the main target of this drug. Genetic models raised doubts that GDF11 is the target of Acvr2b(L79D)-Fc. Here we tested if a GDF11 specific blocking antibody improves β-thalassemia intermedia in mice. Our findings support the genetic data that GDF11 does not play a role in the ineffective erythropoiesis in β-thalassemia. Anti-GDF11 treatment did not change hematocrit, hemoglobin and red blood cell number and it did not improve erythropoiesis. Ex vivo treatment of erythroblasts with recombinant GDF11 did not inhibit red blood cell maturation. Lastly, we identified that inhibiting GDF8 in β-thalassemia mice has a small effect on erythropoiesis and increased hemoglobin levels without being as effective as Acvr2b(L79D)-Fc. Of note, wild-type animals treated with anti-GDF8 did not show changes in any hematology parameters and therefore the small effect we observed might be due to the disease phenotype, but not due to a physiological mechanism involved in erythropoiesis. Taken together, GDF11 is not involved in erythropoiesis but GDF8 may have a minor role in the regulation of ineffective erythropoiesis. Given the small effect of anti-GDF8 on erythropoiesis compared to Acvr2b(L79D)-Fc, we conclude that either there is another target or several targets of Acvr2b(L79D)-Fc driving ineffective erythropoiesis, or that Acvr2b(L79D)-Fc efficacy is due to it altering the overall BMP/GDF/Activin ligand and receptor balance. Disclosures Lob: Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Kravets:Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Miloscio:Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Mastaitis:Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Economides:Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Hatsell:Regeneron Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company.

scholarly journals Rapamycin (Sirolimus) and Rap-536 Increase Red Blood Cell Parameters through Distinct Mechanisms in Wild-Type and Thalassemic Mice

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 17-17
Author(s):  
Melih Acar ◽  
Madhulika Jupelli ◽  
Kyle MacBeth ◽  
Martin Schwickart
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Single Agent ◽  
Beta Thalassemia ◽  
Percentage Increase ◽  
Wild Type ◽  
Publicly Traded ◽  
Cell Parameters

Luspatercept, a fusion protein composed of a modified activin receptor type-2B (ActRIIB) and IgG1 Fc, is a novel erythroid maturation agent that has been shown to increase red blood cell (RBC) and hemoglobin (Hb) levels. Luspatercept binds to and sequesters several endogenous transforming growth factor-beta superfamily ligands, thereby diminishing Smad2/3 signaling. RAP-536, the murine analog of luspatercept, has been shown to induce erythroblast maturation and increase RBC, Hb, and hematocrit levels in wild-type (WT) mice and in murine disease models of beta-thalassemia and myelodysplastic syndromes. Previous studies have shown that rapamycin (sirolimus), an mTOR inhibitor, improved anemia in a mouse model of beta-thalassemia by activating the autophagy pathway. In this study, rapamycin was tested in combination with RAP-536 by treating WT mice and th3/+ mice (a beta-thalassemia disease model; B6.129P2-Hbb-b1tm1Unc Hbb-b2tm1Unc/J) with vehicle, RAP-536 10 mg/kg twice weekly, rapamycin 4 mg/kg daily, or RAP-536 plus rapamycin for 2 weeks. Single-agent dosing with either RAP-536 or rapamycin increased RBC, Hb, and hematocrit levels significantly compared with vehicle treatment in both WT and th3/+ mice (Figure). The percentage increase in RBC, Hb, and hematocrit levels upon RAP-536 or rapamycin administration was substantially higher in th3/+ mice than in WT mice. Interestingly, much higher and significant increases in RBC and Hb levels in both WT and th3/+ mice, and in hematocrit levels in th3/+ mice, were observed with RAP-536 plus rapamycin, when compared with the single agents. For example, in th3/+ mice, the increase in Hb levels compared with vehicle control was 19.2% with RAP-536 alone, 13.0% with rapamycin alone, and 44.7% with RAP-536 plus rapamycin (Figure). In th3/+ mice, RAP-536 plus rapamycin treatment also significantly reduced spleen enlargement compared with vehicle (P < 0.001). RAP-536 increased and rapamycin decreased overall reticulocyte levels and immature reticulocyte relative percentages in whole reticulocyte populations in the blood of WT mice, suggesting that RAP-536 and rapamycin have different mechanisms of action through which they increase RBC and Hb levels. Altogether, these preclinical results provide a rationale for combining rapamycin, and potentially other mTOR inhibitors, with luspatercept to treat anemia associated with beta-thalassemia. Disclosures Acar: Bristol Myers Squibb: Ended employment in the past 24 months. Jupelli:Bristol Myers Squibb: Current Employment. MacBeth:Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Schwickart:Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company.

Prevalence of Red Blood Cell Alloimmunization Among Beta-Thalassemia and Sickle Cell Anemia Patients: a Study from Saudi Arabia

2021 ◽  
Vol 67 (10/2021) ◽  
Author(s):  
Raed Felimban ◽  
Ahmed Alsharyufi ◽  
Jasem Aljehani ◽  
Ahmed Sahlool ◽  
Hamead Aljabri ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Blood Cell ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Red Blood Cell ◽  
Beta Thalassemia

scholarly journals Unusual combination and existence of hemolytic anemias; Thalassemia and G6PD deficient anemia in female patient

2018 ◽  
Vol 6 (4) ◽  
pp. 308-314
Author(s):  
Abdulhamza Rajooj Hmood ◽  
Rawaa Hatif Abd
Keyword(s):  
Hemolytic Anemia ◽  
Broad Bean ◽  
Beta Thalassemia ◽  
Thalassemia Intermedia ◽  
Ineffective Erythropoiesis ◽  
Acid Therapy ◽  
First Case ◽  
Unusual Combination ◽  
Appropriate Therapy ◽  
Carrier Diagnosis

Beta-thalassemia intermedia exhibits feature of ineffective erythropoiesis and hemolytic anemia. Diagnosis can be made via hemoglobin electrophoresis. G6PD deficiency is an X-linked recessive disorder commonly affecting males while females are carrier. Diagnosis is made by measuring G6PD level. A 19-year old pregnant lady, known case of β-thalassemia intermedia, had been presented with episode of acute hemolytic anemia. Investigations were highly suggestive of G6PD deficient anemia. This was confirmed with low G6PD level. Back to her immediate history, consumption of broad bean was ascertained. After appropriate therapy, the patient felt better and her medical derangement was normalized. She delivered normally and kept on life-long folic acid therapy. The importance of recording such a case report is to expect unusual combination of hemolytic anemia despite the uncommon finding of X-linked recessive disorder in women. This was the first case recorded in Karbala province

Effect of warming and infusion of red blood cell concentrates on markers of haemolysis: An ex vivo simulation study

2020 ◽  
Author(s):  
Maria Paula Oliveira Pires ◽  
Maria Angélica Sorgini Peterlini ◽  
Amanda J. Ullman ◽  
Andrew C. Bulmer ◽  
Claire M. Rickard ◽  
...  
Keyword(s):  
Blood Cell ◽  
Simulation Study ◽  
Red Blood Cell ◽  
Ex Vivo

scholarly journals Red blood cell alloimmunisation and autoimmunisation in transfusion dependent beta thalassemics from Southern India

2015 ◽  
Vol 05 (03) ◽  
pp. 004-008
Author(s):  
Mohammed Saleem E. K. ◽  
Soundarya Mahalingam ◽  
Shamee Shastri ◽  
Kamalakshi G. Bhat
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Beta Thalassemia ◽  
Red Cell ◽  
Transfusion Therapy ◽  
Female Ratio ◽  
Antibody Screening ◽  
Cell Antigen ◽  
Low Ionic Strength ◽  
Male To Female

AbstractThe development of red blood cell (RBC) isoimmunization with alloantibodies and autoantibodies complicate transfusion therapy in multiply transfused thalassemia patients. We conducted a study to analyse the frequency in our population. Clinical and antibody profile from 55 multiply transfused thalassemic patients who were receiving transfusions were collected and analyzed prospectively. A commercially available 3 cell antigen panel was used for the antibody screening procedure. If antibody screening with the 3-cell antigen panel was positive, an extended 11-cell antigen panel was used for antibody identification in LISS (Low Ionic Strength Solution). All patients received blood matched for only ABO and Rh (D) antigens. A total of 55 transfusion dependent â thalassemics were included in this study out of which 30 (54.55%) were males and 25(45.45%) females with a male to female ratio of 1.2: 1. Frequency of red cell alloimmunization in this study was found to be 1.8%. None of the patients developed red cell autoimmunization. The alloantibody identified in the the patient who developed alloimmunisation was was anti-K. In conclusion, the transfusion of matched blood is essential for chronically transfused beta thalassemia patients in order to avoid alloimmunization.

scholarly journals Infusion of Autologous Retrodifferentiated Stem Cells into Patients with Beta-Thalassemia

2006 ◽  
Vol 6 ◽  
pp. 1278-1297 ◽  
Author(s):  
Ilham Saleh Abuljadayel ◽  
Tasnim Ahsan ◽  
Huma Quereshi ◽  
Shakil Rizvi ◽  
Tamseela Ahmed ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Blood Cell ◽  
Red Blood Cell ◽  
White Blood Cells ◽  
Fetal Hemoglobin ◽  
Beta Thalassemia ◽  
Mean Corpuscular Hemoglobin ◽  
Beta Globin ◽  
Globin Chain ◽  
Adult Hemoglobin

Beta-thalassemia is a genetic, red blood cell disorder affecting the beta-globin chain of the adult hemoglobin gene. This results in excess accumulation of unpaired alpha-chain gene products leading to reduced red blood cell life span and the development of severe anemia. Current treatment of this disease involves regular blood transfusion and adjunct chelation therapy to lower blood transfusion–induced iron overload. Fetal hemoglobin switching agents have been proposed to treat genetic blood disorders, such as sickle cell anemia and beta-thalassemia, in an effort to compensate for the dysfunctional form of the beta-globin chain in adult hemoglobin. The rationale behind this approach is to pair the excess normal alpha-globin chain with the alternative fetal gamma-chain to promote red blood cell survival and ameliorate the anemia. Reprogramming of differentiation in intact, mature, adult white blood cells in response to inclusion of monoclonal antibody CR3/43 has been described. This form of retrograde development has been termed “retrodifferentiation”, with the ability to re-express a variety of stem cell markers in a heterogeneous population of white blood cells. This form of reprogramming, or reontogeny, to a more pluripotent stem cell state ought to recapitulate early hematopoiesis and facilitate expression of a fetal and/or adult program of hemoglobin synthesis or regeneration on infusion and subsequent redifferentiation. Herein, the outcome of infusion of autologous retrodifferentiated stem cells (RSC) into 21 patients with beta-thalassemia is described. Over 6 months, Infusion of 3-h autologous RSC subjected to hematopoietic-conducive conditions into patients with beta-thalassemia reduced mean blood transfusion requirement, increased mean fetal hemoglobin synthesis, and significantly lowered mean serum ferritin. This was always accompanied by an increase in mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in such patients. No adverse side effects in response to the infusion of autologous RSC were noted.This novel clinical procedure may profoundly modify the devastating course of many genetic disorders in an autologous setting, thus paving the way to harnessing pluripotency from differentiated cells to regenerate transiently an otherwise genetically degenerate tissue such as thalassemic blood.

Ineffective Erythropoiesis and Production of Normoblasts with a Beta Thalassemia Major Phenotype Using CD34+ Cells From Healthy Donors

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1085-1085
Author(s):  
Y.Terry Lee ◽  
Colleen Byrnes ◽  
Emily Riehm Meier ◽  
Antoinette Rabel ◽  
Jeffery L. Miller
Keyword(s):  
Ex Vivo ◽  
Globin Gene ◽  
Thalassemia Major ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Ineffective Erythropoiesis ◽  
Globin Mrna ◽  
Cell Counts ◽  
Cd34 Cells ◽  
Gene And Protein Expression

Abstract Abstract 1085 Reversal of anemia is the major target of thalassemia research, but studies of the molecular and cellular basis of the ineffective erythropoiesis of thalassemia are limited by access to donor progenitor cells. Here we demonstrate that thalassemic erythropoiesis may be recapitulated ex vivo by reducing the expression of hemoglobin in cultured CD34+ cells. Using lentiviral transduction of progenitor cells obtained from three healthy adult human donors, shRNA molecules were screened for their ability to reduce beta-globin gene and protein expression over 21 days in culture. Cells transduced with a scrambled vector served as donor-matched controls. Among the screened shRNA, one named HBB caused a consistent and significant reduction in beta-globin mRNA and protein. Beta-globin mRNA was reduced to levels <10% (p<0.001) compared to that of the controls (day14/21), while maintaining expression of gamma- and alpha-globin mRNA. HPLC was performed on an equivalent number of cells sampled on culture day 21 for hemoglobin type (HbA vs. HbF) and quantitation (area under each HPLC peak). The HbA peak was reduced by 96%, and there was a minor increase in the HbF peak (1.6 fold) after HBB transduction. Based upon these quantitative changes in hemoglobin, HbF represented 49.3±9.3% in the HBB transduced population compared with 2.9±0.7% (p<0.01) in controls. On culture day 14, there was no significant difference in glycophorin A (CD235), transferrin receptor (CD71), or cellular morphology despite the reduction in beta-globin mRNA. However, impaired terminal differentiation was detected by retainment of surface CD71 and a lack of enucleation during the third week of culture. Cell counts were lower in HBB transduced cells during the final stages of erythroid differentiation with a 61% (p=0.03) reduction in total cell counts by day 21 when compared to controls. Annexin V assay on day 21 also demonstrated increased phosphatidylserine expression in the HBB transduced cells [HBB=55.7±14.4% vs. Control=25.0±3.0%] in association with the decreased terminal differentiation. GDF15 quantitation demonstrated a significant (p=0.006) increase in the culture supernatants of HBB transduced cells. Sorted cytospin preparations revealed a distinct population of mature normoblasts containing a highly condensed nucleus surrounded by a thin ring of hypochromic cytoplasm. Reduction of erythroblast beta-globin gene and protein expression to levels associated with beta thalassemia major in humans causes ineffective erythropoiesis ex vivo by reducing cell production, increasing surface expression of phosphatidylserine, and impairing enucleation during terminal maturation. Efforts are now underway to use the culture system to explore mechanisms whereby reduced hemoglobin synthesis causes normoblast defects, and for screening of chemical and genetic rescue therapies for the thalassemic erythroid phenotype. Disclosures: No relevant conflicts of interest to declare.

Hemoglobin levels and red blood cell indices in mid-gestational fetuses with beta-thalassemia/HbE, beta-thalassemia trait or Hb E trait and normal fetuses

2013 ◽  
Vol 33 (13) ◽  
pp. 1238-1241
Author(s):  
Kasemsri Srisupundit ◽  
Chanane Wanapirak ◽  
Supatra Sirichotiyakul ◽  
Fuanglada Tongprasert ◽  
Suchaya Leuwan ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Beta Thalassemia ◽  
Hb E ◽  
Red Blood Cell Indices ◽  
Thalassemia Trait

scholarly journals Beta-thalassemia minor is a beneficial determinant of red blood cell storage lesion

Haematologica ◽  
2021 ◽  
Author(s):  
Vassilis L. Tzounakas ◽  
Alkmini T. Anastasiadi ◽  
Davide Stefanoni ◽  
Francesca Cendali ◽  
Lorenzo Bertolone ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Pentose Phosphate ◽  
Oxidation Products ◽  
Lower Percentage ◽  
Beta Thalassemia ◽  
Potassium Accumulation ◽  
Hexosamine Pathway ◽  
Thalassemia Minor ◽  
Haematological Profile

Blood donor genetics and lifestyle affect the quality of red blood cell (RBC) storage. Heterozygotes for beta-thalassaemia (βThal+) constitute a non-negligible proportion of blood donors in the Mediterranean and other geographical areas. The unique haematological profile of βThal+ could affect capacity of enduring storage stress, however, the storability of βThal+ RBCs is largely unknown. In this study, RBCs from 18 βThal+ donors were stored in the cold and profiled for primary (haemolysis) and secondary (phosphatidylserine exposure, potassium leakage, oxidative stress) quality measures, and metabolomics, versus sex- and age-matched controls. The βThal+ units exhibited better levels of storage haemolysis and susceptibility to lysis following osmotic, oxidative and mechanical insults. Moreover, βThal+ RBCs had a lower percentage of surface removal signaling, reactive oxygen species and oxidative defects to membrane components at late stages of storage. Lower potassium accumulation and higher urate-dependent antioxidant capacity were noted in the βThal+ supernatant. Full metabolomics analyses revealed alterations in purine and arginine pathways at baseline, along with activation of pentose phosphate pathway and glycolysis upstream to pyruvate kinase in βThal+ RBCs. Upon storage, substantial changes were observed in arginine, purine and vitamin B6 metabolism, as well as in the hexosamine pathway. A high degree of glutamate generation in βThal+ RBCs was accompanied by low levels of purine oxidation products (IMP, hypoxanthine, allantoin). The βThal mutations impact the metabolism and the susceptibility to haemolysis of stored RBCs, suggesting good post-transfusion recovery. However, haemoglobin increment and other clinical outcomes of βThal+ RBC transfusion deserve elucidation by future studies.

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