The cellular distribution of A14-( 125I)monoiodoinsulin after incubation with cultured human lymphocytes (IM-9). A quantitative electronmicroscope autoradiographic study

Abstract

Cultured human lymphocytes of the IM-9 line were incubated with ( 125I)monoiodoinsulin for 3 to 150 min at 37 °C and the location of the bound insulin was determined by quantitative electron microscope autoradiography. The radioactivity was primarily associated with the plasmamembrane although a few cells showed a limited endocytic uptake. The intracellular radioactivity was not more than 3–4 per cent of the total cell-associated radioactivity at any time and no preferential association to the nucleus could be detected.