THE EFFECT OF SURFACE-ACTIVE AGENTS ON PHAGOCYTOSIS

Abstract

The effect of 52 surface-active agents on the phagocytic activity of human neutrophiles was tested in vitro. Five of these (Triton N-100, Tween 20, Na-abietyl sulfate, decyl benzene Na-monosul- fate, and carboxymethyl cellulose) at least doubled the mean number of bacteria ingested per leucocyte, as compared to con trol values, when the blood was incubated in the presence of the compound, 0.0005% by wt., before the addition of the bacterial suspension. Similarly, an increase in % of neutrophiles active was found when the most active compound, Triton N-100, was tested with human and with mouse neutrophiles. This same sub stance, injd. intraperit. into mice, elevated the phagocytic activity of the blood granulocytes, evaluated in vitro, in doses as small as 0.2 mg. in 0.2 cc. of physiol. saline. When injns. were repeated every 4 hrs. for 3 days, the enhanced phagocytic function was maintained. A similar treatment, however, failed to protect mice against exptly. induced infections with Salmonella typhimurium, possibly because no change in phagocytosis occurred when both blood cells and bacteria were incubated in the presence of the detergent prior to mixing, and a decrease in phagocytosis followed incubation of the bacteria alone. These results are in agreement with Fenn''s theoretical formulation of phagocytosis.