TY - JOUR
T1 - Fetal and adult hemoglobin production during adult erythropoiesis
T2 - Coordinate expression correlates with cell proliferation
AU - Wojda, Urszula
AU - Noel, Pierre
AU - Miller, Jeffery L.
PY - 2002/4/15
Y1 - 2002/4/15
N2 - The design and evaluation of therapies for the sickle cell and β-thalassemia syndromes rely on our understanding of hemoglobin accumulation during human erythropoiesis. Here we report direct measurements of hemoglobin composition and messenger RNA (mRNA) levels in cultured CD34+ cells and correlate those measurements with studies of freshly obtained bone marrow samples. Hemoglobin levels in differentiating cells were also compared with morphologic, immunophenotypic, and cell cycle assessments. A population of large preproerythroblasts was first identified within 24 hours and became the dominant population by day 5. The transition from proerythroblast to basophilic normoblast occurred later, from days 7 to 9, and correlated with a peak of 74.1 ± 3.9% of the cells in the S phase of cell cycle. Orthochromatic normoblasts were the dominant and final cell type by day 13. High-performance liquid chromatographybased quantitation of fetal (HbF) and adult (HbA) hemoglobin and real-time polymerase chain reaction globin mRNA quantitation demonstrated a coordinate rise in the accumulation of both proteins and mRNA among these developmentally staged populations. Quantitative analyses on freshly sorted bone marrow populations demonstrated a similar rising pattern with β-globin and HbA as the dominant species at both early and late stages of differentiation. We found no evidence for HbF dominant populations or switching during differentiation in adult cells. Instead, rapid increases in both HbF (heterocellular) and HbA (pancellular) content were observed, which coincided with the apex in cell cycling and the proerythroblast-basophilic normoblast transition. Based on these measurements, we conclude that HbF and HbA content are regulated with the rate of proliferation during adult erythropoiesis.
AB - The design and evaluation of therapies for the sickle cell and β-thalassemia syndromes rely on our understanding of hemoglobin accumulation during human erythropoiesis. Here we report direct measurements of hemoglobin composition and messenger RNA (mRNA) levels in cultured CD34+ cells and correlate those measurements with studies of freshly obtained bone marrow samples. Hemoglobin levels in differentiating cells were also compared with morphologic, immunophenotypic, and cell cycle assessments. A population of large preproerythroblasts was first identified within 24 hours and became the dominant population by day 5. The transition from proerythroblast to basophilic normoblast occurred later, from days 7 to 9, and correlated with a peak of 74.1 ± 3.9% of the cells in the S phase of cell cycle. Orthochromatic normoblasts were the dominant and final cell type by day 13. High-performance liquid chromatographybased quantitation of fetal (HbF) and adult (HbA) hemoglobin and real-time polymerase chain reaction globin mRNA quantitation demonstrated a coordinate rise in the accumulation of both proteins and mRNA among these developmentally staged populations. Quantitative analyses on freshly sorted bone marrow populations demonstrated a similar rising pattern with β-globin and HbA as the dominant species at both early and late stages of differentiation. We found no evidence for HbF dominant populations or switching during differentiation in adult cells. Instead, rapid increases in both HbF (heterocellular) and HbA (pancellular) content were observed, which coincided with the apex in cell cycling and the proerythroblast-basophilic normoblast transition. Based on these measurements, we conclude that HbF and HbA content are regulated with the rate of proliferation during adult erythropoiesis.
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U2 - 10.1182/blood.V99.8.3005
DO - 10.1182/blood.V99.8.3005
M3 - Article
C2 - 11929793
AN - SCOPUS:0037089318
SN - 0006-4971
VL - 99
SP - 3005
EP - 3013
JO - Blood
JF - Blood
IS - 8
ER -