Identification and quantitation of embryonic and three types of fetal hemoglobin produced on induction of the human pluripotent leukemia cell line K‐562 with hemin

Abstract

The hemoglobins synthesized by the pluripotent K-562 leukemia cell line of human origin after induction with hemin have been isolated by DEAE-cellulose chromatography and characterized by electrophoresis, high pressure liquid chromatography, and a radioimmunological assay. Six hemoglobin zones have been observed with the following likely compositions. Zone 1: alpha 2 epsilon 2, or HB Gower-2; zone 2: zeta 2 epsilon 2, or HB Gower-1; zone 3: zeta 2 gamma 2, or HB Portland-I; zone 4: Hb F, or alpha 2 gamma 2; zone 5: a mixture of acetylated HB Portland-I and Hb F; zone 6: Hb Bart's, or gamma 4. The embryonic Hbs (zones 1, 2, and 3) constituted 50%-75% of the total Hb present; the quantities varied from one experiment to the other. Both Hb Gower-1 and Hb Gower-2 were present. The gamma chain was heterogeneous and contained the G gamma, A gamma I, and A gamma T types in a ratio of about 4:2:1, indicating a heterozygosity for the Ile leads to Thr substitution at position gamma 75. The methodology used can be applied for additional studies evaluating quantitative changes in Hb types due to in vitro manipulations.