Studies on the Heterogeneity and Serum Binding of Human Growth Hormone

Abstract

Studies on the elution from columns of G200 Sephadex of unlabeled, fluoresceinlabeled and radioiodine-labeled Raben human growth hormone, alone and in the presence of human serum, suggest that this hormone preparation contains a partially denatured component with markedly diminished antigenic properties. A tendency to molecular aggregation, apparently aggravated by increased hormone concentration and reduced pH, and an affinity for macroglobulins are characteristic of the denatured component. Further denaturation occurs with radioiodination, and the affinity of the altered component for macroglobulin may account for the apparent binding by macroglobulin of radioiodinated human growth hormone.