Intranuclear Hemoglobin in Erythroblasts of β-Thalassemia

The amount and distribution of intranuclear hemoglobin in erythroblasts of normal subjects and patients with homozygous β-thalassemia were studied by microspectrophotometric methods. The mean intranuclear hemoglobin content of the mature erythroblasts represented 33%-40% of the total hemoglobin content both in normal and thalassemic cells. Distinct absorption peaks in transmission scanning lines recorded over thalassemic erythroblasts suggested the presence of intranuclear hemoglobin precipitation in some cells. Similar characteristic absorption peaks of denatured ferric hemoglobin were recorded over large inclusions of the cytoplasm and small intranuclear precipitates. Intranuclear inclusion bodies may be responsible for the disturbance of erythroblast proliferation in thalassemia, thus explaining in part the ineffective erythropoiesis occurring in this disease.