title: Polyclonal activation of murine B cells by a membrane proteoglycan of Klebsiella pneumoniae.
abstract: The lymphocyte activating properties of a membrane proteoglycan (MPG) extracted from a mutant non-encapsulated strain of Klebsiella pneumoniae (Kp) (biotype a I-145) were investigated. Kp MPG induced a strong proliferative response of BALB/c spleen cells and Peyer's patches cells. Thymidine incorporation was dose-related (from 1 to 100 micrograms Kp MPG/ml) and reached a maximum at day 3. It was not reduced by removal of most adherent cells, nor by depletion of Thy1-2 positive cells, but it was abrogated by removal of surface immunoglobulin bearing cells. Spleen cells from nude mice and those from C3H/Hej mice were strongly stimulated by Kp MPG. Conversely Kp MPG did not induce interleukin 2 production and did not trigger the proliferation of thymocytes but stimulated interleukin 1 production by adherent spleen cells. Finally, unfractionated or B-enriched spleen cells cultured with Kp MPG synthesized IgM and, to a lesser extent, IgG and IgA. It is concluded that Kp MPG is a T-independent polyclonal B cell activator and an inducer of interleukin 1 production.
authors.affiliation: INSERM U.80, CNRS ERA 1177, Lyon, France.
authors.forename: I
authors.initials: I
authors.lastname: Millet
authors.forename: S
authors.initials: S
authors.lastname: Lafont
authors.forename: A
authors.initials: A
authors.lastname: de Fraissinette
authors.forename: M
authors.initials: M
authors.lastname: Jeannin
authors.forename: J P
authors.initials: JP
authors.lastname: Revillard
authors.forename: G
authors.initials: G
authors.lastname: Normier
authors.forename: L
authors.initials: L
authors.lastname: Dussourd d'Hinterland
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D001426:Bacterial Proteins / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D005260:Female; D007136:Immunoglobulins / Q000096:biosynthesis; D007375:Interleukin-1 / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D007711:Klebsiella pneumoniae; D008213:Lymphocyte Activation / Q000187:drug effects*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008819:Mice, Nude; D011509:Proteoglycans / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; D007136:Immunoglobulins; D007375:Interleukin-1; D007376:Interleukin-2; D011509:Proteoglycans