title: The binding of insulin-like growth factor II to the erythroleukemia cell line K562.
abstract: The erythroleukemia cell line K562 was previously shown to have specific binding sites for insulin but not for insulin-like growth factor I (IGF-I). In this study the presence of specific receptors for insulin-like growth factor II (IGF-II) is established. Scatchard analysis of the competition curve for IGF-II disclosed a non-cooperative binding kinetic with a calculated affinity constant 2.4 X 10(8) M-1 and a receptor number of 4.8 X 10(4) sites/cell. IGF-I displayed 10% crossreactivity over the IGF-II receptor but insulin did not crossreact at all. Instead insulin, present in high concentrations, enhanced the binding of IGF-II. The presence of IGF II but not IGF-I receptors makes the K562 cell line suitable for studying properties of the type-2 receptor.
mesh_terms: D001665:Binding Sites; D001667:Binding, Competitive; D002460:Cell Line; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007700:Kinetics; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism; D017451:Receptors, Somatomedin; D013002:Somatomedins / Q000378:metabolism*
chemical_list: D007328:Insulin; D010455:Peptides; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; D013002:Somatomedins