Inhibition of zymosan-induced alternative complement pathway activation by concanavalin A.

Zymosan, a polysaccharide composed primarily of glucan and mannan residues, activates the complement system through the alternative complement pathway. We showed that zymosan-induced complement activation is inhibited by zymosan-bound lectins with carbohydrate specificities for mannosyl and glycosyl residues. Lectins unable to bind mannosyl or glucosyl residues did not inhibit zymosan-induced complement activation.