SOMNOGENIC ACTIVITY OF MURAMYL PEPTIDE-DERIVED IMMUNE ADJUVANTS

Muramyl peptides (MPs) possess immunostimulatory, pyrogenic and somnog enic activities. The structural requirements of MPs for each of these activities are different though certain MPs, e.g. murayl dipeptide (NA M-L-ala-D-isogln) possess all three activities. Several MPs are propos ed for use as immune adjuvants; somnogenic and pyrogenic activities wo uld be considered adverse side effects of such compounds. We report he re that some of the putative adjuvants, GIF101, WG209 and MDP-threonin e lack somnogenic and pyrogenic activities. Current results also expan d our understanding of the structural requirements for these activitie s. Major findings are that the addition of the dipeptide L-ala-D-isogl n to NAG-NAM-L-ala-D-isogln blocks the activity of the latter compound and that the amino sugar moiety of MPs, NAM, is unnecessary for somno genic and pyrogenic activity.