INDIUM-111-LABELED CELLULAR BLOOD COMPONENTS - MECHANISM OF LABELING AND INTRACELLULAR LOCATION IN HUMAN NEUTROPHILS

Abstract

Human neutrophils were labeled with 111In oxine by incubation at room temperature, and the fate of the oxine and the intracellular location of the 111In were determined. Neutral (1:3) 111In oxine complex diffuses rapidly across the cell membrane and then dissociates. Some of the oxine leaves the cell and the 111In binds intracellularly. After short periods of incubation, the label is distributed mostly to 4 soluble components, a small proportion of which had a distribution similar to that of specific and azurophil granules. After longer incubation periods there was relatively less radioactivity with the soluble components and probably more attached to the particulate material. A small peak of radioactivity also appeared in the region of DNA distribution, but no confirmation was obtained for the association of the 111In radioactivity with DNA.