Inhibition of 14C-labeled amino acid incorporation into protein by particles and surface-active agents in human granulocytes.

Contact of human polymorphonuclear leukocytes with latex or zymosan particles resulted in inhibition of incorporation of 14C-labeled amino acids into protein in the phagocytosing cells. The surface-active agents, concanavalin A and digitonin, exerted the same inhibitory activity on 14C-labeled amino acid incorporation into protein in human granulocytes. The inhibition of 14C label incorporation was dose dependent and the half-maximal effect per 10(7) cells was found at 0.8 mg of latex (0.79 micrometer in diameter), 0.25 mg of serum-coated zymosan and 35 microgram of digitonin/ml of the incubation medium. Amino acid transport (14C-labeled amino acids or amino[14C]isobutyrate) was the same in the resting and phagocytosing granulocytes. These results suggest that the incorporation of 14C-labeled amino acids into protein in human granulocytes is in some way connected to alteration in the cell plasma membrane.