[Effect on human complement of blastolysin and the glycopeptide (MDP and GMDP) and carbohydrate fragments of peptidoglycans].

Along with complement activation by the classical pathway, blastolysin, an antitumor and adjuvant preparation of Lactobacillus bulgaricus peptidoglycans, effectively inhibits the transformation of C3 in to C5 convertase. Values of inhibition maximum and dissociation constants of the reversible C3b-acceptor complex for blastolysin and main immunological active structural moieties of peptidoglycans (GMDP, MDP) and their inactive carbohydrate components (N-acetylglucosaminyl-N-acetylmuramic acid, N-acetylglucosamine, and N-acetylmuramic acid) have been determined. Immunostimulator concentrations for blastolysin, GMDP, and MDP in inhibition of the C5 convertase formation (C3b binding) correlate with their doses in vivo (animal blood), displaying antitumor activity.