The ,8-elimination procedure was used to obtain two major fragments of Mycobacterium avium glycopeptidolipid antigens. The lipopeptide fragment, not the oligosaccharide, diminished the mitogen-induced blastogenic response of spleen cells at concentrations lower than those which affected viability. Electron microscopy revealed an internalization of lipopeptide and disruption of intracellular organization.on July 31, 2020 by guest http://iai.asm.org/ Downloaded from