Different Concentrations of Chemotactic Factors Can Produce Attraction or Migration Inhibition of Leukocytes

Abstract

Parallel tests were conducted utilizing, the capillary tube migration test and the Boyden chamber assay, in order to determine whether the decrease in leukocyte chemotaxis that occurs if overoptimal cytotaxin concentrations are applied is due to migration inhibition. Overoptimal doses of casein produced decreased chemotactic response and migration inhibition for both rabbit macrophages and neutrophils. However, guinea pig neutrophils exhibited no decrease in chemotaxis despite high casein doses. Overoptimal doses of acid-denatured anaphylatoxin produced a decreased chemotactic response and migration inhibition of neutrophils. In both assays, this agent showed no effect upon macrophages. It is concluded that a chemotactic signal at different concentrations can elicit unidirectional migration or migration inhibition. Accordingly, chemotactic leukocyte attraction could be antagonistically regulated not only by serum-derived and lymphocyte-derived migration inhibitory factors but also by high doses of the chemotactic factor itself. Thus, the Boyden chamber technique can measure both chemotactic migration and migration inhibition phenomena.

Monocyte and Neutrophil Chemotactic Activity of Normal and Diluted Human Serum and Plasma

“…Experiments in which the cells had been resuspended in undiluted ser um before filling them into the upper com partment confirmed this notion. The finding that heated serum (30 min, 56 °C) con tained the same inhibitory capacity seems to suggest that inhibition was not due to an overoptimal concentration of a chemotactic factor [10] present in undiluted serum which would have been destroyed by heat ing. Experiments not shown here confirmed presence of (a) separate chemotaxis or migra tion inhibitor(s).…”