Quantitation of hemoglobin in single erythrocytes with and without fetal hemoglobin.

The hemoglobin content was determined by microspectrophotometry in single erythrocytes with and without fetal hemoglobin (Hb F) from 16 normal subjects, 30 patients with anemia of different etiology and severity and 20 individuals with thalassemic disorders. Hb F-containing cells were identified by an indirect immunofluorescent method. The relative single cell value: total extinction (TE) at 415 nm, cell size (A) and the ratio TE/A, were used to indicate single cell values of MCH, MCV and MCHC respectively. The TE (MCH) and/or TE/A (MCHC) did not differ significantly between Hb F-containing (F-cells) and non-F cells in normal subjects and in cases with various forms of acquired anemia. On the contrary, the TE and/or TE/A of F-cells was found significantly higher in F compared to non-F cells in 11 of 20 (55%) of the cases with thalassemia. The results suggest that, in some cases of thalassemia, hemoglobin F is an important substitute for hemoglobin A and may improve the level of hemoglobinization.