background: efficient induction of fetal hemoglobin (hbf) is considered as an effective therapeutic approach in beta thalassemia. hbf inducer agents can induce the expression of γ-globin gene and produce high levels of hbf via different epigenetic and molecular mechanisms. thalidomide and sodium butyrate are known as hbf inducer drugs. material and methods : cd133 + stem cells were isolated fro...

Cytotoxic drugs increase circulating fetal hemoglobin levels. We examined the mechanism by measuring the fetal hemoglobin produced per BFU-E-derived erythroblast following hydroxyurea treatment in vivo and in vitro. Treatment of four sickle cell patients increased the percentage of circulating F reticulocytes. The frequencies of bone marrow or peripheral blood BFU-E or CFU-E-derived colonies an...

Reactivation of fetal hemoglobin (HbF) in adults ameliorates the severity of the common β-globin disorders. The transcription factor BCL11A is a critical modulator of hemoglobin switching and HbF silencing, yet the molecular mechanism through which BCL11A coordinates the developmental switch is incompletely understood. Particularly, the identities of BCL11A cooperating protein complexes and the...

I N A RECENT REPORT Lie-Injo and 1 described a condition char.. acterized by a deficiency of both types I and 112 (also designated B and C) of carbonic anhydrase. This deficiency, though associated with a high level of fetal hemoglobin, was not due to hemoglobinopathy, hereditary persistence of fetal hemoglobin, or any of the known types of thalassemia. Because of lack of proof of hereditary ba...

Colony assays are now available to study erythroid differentiation at three different levels. Mixed hemopoietic colonies represent progeny of pluripotent progenitors (CFU-GEMM). Erythroid bursts and cobnies are derived from early (BFU-E) and late precursors (CFU-E) that are committed towards erythropoiesis. The three different types of colonies were examined for their content of fetal hemoglobi...

Strategies to increase fetal hemoglobin (HbF) levels can ameliorate symptoms and improve the lives of β-hemoglobinopathy patients. Although most studies have focused on induction of γ-globin gene expression as an approach to induce HbF, we hypothesized that post-transcriptional regulation of HbF plays an underappreciated yet important role in controlling HbF levels. In the present study, we inv...

A new hematopoietic growth factor (Steel factor) has been identified which stimulates erythroid proliferation both in vitro and in vivo. We evaluated the influence of recombinant Steel factor on hemoglobin synthesis in peripheral blood (PB) BFU-E-derived cells from normal donors by radioimmunoassay (RIA) and compared it with stimulation with GM-CSF and interleukin-3 (IL-3). Only Steel factor st...

BACKGROUND Sickle hemoglobin is the most common abnormal hemoglobin in the United States. Hemoglobin S arises as a result of a single amino acid substitution (glutamic acid to valin at position 6 of the β-globine chain). The presence of fetal hemoglobin (HbF) plays a relatively protective role since a significant amount of HbF interferes with HbS polymerization, the pathogenesis mechanism of th...

A B S T R A C T By using a methylcellulose clonal assay, we cultured peripheral blood erythropoietic precursors from a patient with sickle cell anemia, a patient with sickle cell hemoglobin C disease, and a normal volunteer. We then analyzed the synthetic rates ofadult and fetal hemoglobins (Hb) in individual erythropoietic bursts. Hb were labeled with '4C-amino acids in culture, separated by s...