Water-soluble specific growth hormone binding sites from cultured human lymphocytes: preparation and partial characterization.

摘要: Cultured human lymphocytes (IM-9 cell line) have specific binding sites or receptors for growth hormone (hGH). Under appropriate conditions, this material is spontaneously released into the incubation medium and solubilized without use of detergents. This water-soluble preparation binds [125I]iodo-hGH with same specificity as on intact cell. Unlabeled hGH, but not porcine insulin, competes labeled hGH to soluble preparation. Growth preparations varying purity compete in rank order they IM-9 lymphocyte. incubated with, bound to, partially degraded, while that protected from degradation, its ability rebind fresh cells enhanced. The [125I]iodo-hGH-soluble complex can be dissociated ...