Lectins modulate prostaglandin E2 production by rat peritoneal macrophages.

The effect of Aloctin A (Alo A), a lectin having anti-inflammatory activities, on prostaglandin (PG) E2 production by activated rat peritoneal macrophages was compared with that of concanavalin A (Con A), wheat germ agglutinin (WGA), plsum sativum agglutinin (PSA) and soybean agglutinin (SBA). Alo A, WGA, Con A and PSA at 10 micrograms per ml inhibited PG E2 production. But SBA, even at a dose of 1 microgram per ml, stimulated PG E2 production. The inhibition by Alo A treatment of the release of radioactivity from (3H)arachidonic acid-labeled macrophages and the stimulation of this release by SBA treatment were observed. The uptake of (51Cr)-labeled sheep red blood cells by the macrophage was inhibited by Alo A, Con A, and PSA, all at 10 micrograms per ml and SBA at 1 microgram per ml, however, WGA at 10 micrograms per ml stimulated the uptake of the sheep red blood cells. The mechanism of the anti-inflammatory properties of Alo A was discussed.