title: The influence of lipopolysaccharide content on the apparent B cell stimulating activity of anti-mu preparations.
abstract: Anti-mu preparations differ greatly in their ability to stimulate mouse B cells to incorporate tritiated thymidine (TdR). We have found that these differences may be due in part to different levels of lipopolysaccharide (LPS) content. In this report we show that LPS concentrations as low as 0.025 ng/ml stimulate the proliferation of T-depleted (C57BL/6 X DBA/2)F1 (B6D2F1) spleen cells, provided that 5 X 10(-5) M 2-mercaptoethanol is also present. Each of six commercial anti-mu preparations tested for LPS content contained more than this amount. We describe a technique that uses polymyxin B-agarose to remove nanogram quantities of LPS from anti-mu preparations. In B6D2F1 B cells, LPS-depleted anti-mu preparations induced much more uniform tritiated thymidine incorporation than did non-depleted preparations; but there was little difference between the two preparations when tested on B cells from C3H/HeJ (LPS hyporesponsive) mice.
authors.affiliation: Department of Microbiology, University of Iowa College of Medicine, Iowa City 52242.
authors.forename: J A
authors.initials: JA
authors.lastname: Wilder
authors.forename: J S
authors.initials: JS
authors.lastname: Cowdery
authors.forename: R F
authors.initials: RF
authors.lastname: Ashman
mesh_terms: D000042:Absorption; D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis*; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D007140:Immunoglobulin Fab Fragments / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis / Q000276:immunology*; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000032:analysis / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011112:Polymyxin B; D012685:Sepharose
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007140:Immunoglobulin Fab Fragments; D007075:Immunoglobulin M; D008070:Lipopolysaccharides; C044203:anti-IgM; D012685:Sepharose; D011112:Polymyxin B