Activation of nuclear factor-kappaB in macrophages by mycoplasmal lipopeptides.
Mycoplasmas are potent macrophage stimulators. The active principle are lipopeptides or lipoproteins with a characteristic N-terminal S-[dihydroxypropyl]-cysteinyl group bearing two ester-bound fatty acids and lacking the amide-bound one common to other bacterial lipoproteins. Using synthetic analogues of mycoplasmal lipopeptides, we investigated activation of the transcription factor NF-kappaB in the C3H/HeJ mouse-derived DMBM-3 cell line. The lipopeptides activated NF-kappaB at below nanomolar concentrations. Activation in the murine system occurred distinctly earlier than TNF-alpha liberation, excluding autocrine stimulation by TNF-alpha. As determined from a supershift experiment, the active NF-kappaB complex consisted of the heterodimer p50/p65(RelA). The relevance of these findings for the inflammatory response to mycoplasmas and for mycoplasma-mediated effects on HIV-infected macrophages is discussed.
Sacht
G
G
Immunobiology Research Group, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Germany.
Märten
A
A
Deiters
U
U
Süssmuth
R
R
Jung
G
G
Wingender
E
E
Mühlradt
P F
PF
D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology / Q000494:pharmacology; D002460:Cell Line; D008074:Lipoproteins / Q000276:immunology / Q000494:pharmacology*; D008262:Macrophage Activation / Q000187:drug effects / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D009174:Mycoplasma; D016328:NF-kappa B / Q000276:immunology*
D001426:Bacterial Proteins; D008074:Lipoproteins; D016328:NF-kappa B