HUMAN GROWTH HORMONE AND ALPHA2-MACROGLOBULIN - A STUDY OF BINDING

The availability of a pure human α2-macroglobulin (α2-M) preparation has prompted a re-examination of its reported binding with human growth hormone (HGH). Incubation of labeled HGH preparations with α2-M did not show significant binding as measured by paper chromatoelectrophoresis, starch gel electrophoresis, or gel filtration. Although a small proportion of HGH traveled with α2-M, an analysis of the results suggests that this is not due to binding by the major component of α2-M. These studies indicate that the major component of α2-M cannot serve as a carrier protein for HGH in human plasma. An expression for the behavior of a dissociating system in gel filtration, applicable to the particular conditions employed in this study, is developed and discussed. © 1969.