Structural features of binding of lipopolysaccharides to murine lymphocytes.
A sensitive hapten-sandwich immunofluorescence technique was used to examine binding of lipopolysaccharide (LPS) at the single-cell level. The structural features governing such binding to murine lymphocytes were investigated by evaluating LPS binding in the presence of a variety of charged molecules and after different target-cell treatments. Polymyxin B, the positively charged proteins egg-white lysozyme and protamine chloride, and the polyanion dextran sulfate inhibited LPS binding to murine lymphocytes. Pretreatment with the proteolytic enzyme pronase and the cross-linking agent paraformaldehyde abolished the capacity of lymphocytes to bind LPS. Inhibition by polymyxin B was less effective when added 30 min after initiation of incubation of LPS with cells at 0 C or when added at the initiation of incubation at 37 C. These results suggest that the interaction between LPS and lymphocytes is a two-stage process, the first of which is dependent on a positively charged membrane protein. The second stage is postulated to be an irreversible hydrophobic interaction between LPS and membrane lipids.
D000818:Animals; D003911:Dextrans / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D008070:Lipopolysaccharides / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D008563:Membrane Lipids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D011112:Polymyxin B / Q000494:pharmacology; D011817:Rabbits
D003911:Dextrans; D008070:Lipopolysaccharides; D008563:Membrane Lipids; D008565:Membrane Proteins; D011112:Polymyxin B