title: Downregulation of the DNA-binding activity of nuclear factor-kappaB p65 subunit in Porphyromonas gingivalis fimbria-induced tolerance.
abstract: Porphyromonas gingivalis fimbriae induce high levels of nuclear factor-kappaB (NF-kappaB)-dependent cytokine release upon primary but not secondary stimulation of monocytic cells (FimA tolerance). In this study, fimbriae induced Toll-like receptor-mediated activation of both p50 and p65 subunits of NF-kappaB upon primary cellular activation. However, activation of the transactivating p65 subunit (but not of the transcriptionally inactive p50 subunit) was significantly inhibited in fimbria-restimulated cells. Moreover, expression of a NF-kappaB-dependent reporter gene was inhibited upon secondary stimulation with fimbriae. NF-kappaB p65 downregulation may thus contribute to induction of FimA tolerance.
authors.affiliation: Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70119, USA. ghajis@lsuhsc.edu
authors.forename: George
authors.initials: G
authors.lastname: Hajishengallis
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Genco
mesh_terms: D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D004247:DNA / Q000378:metabolism*; D015536:Down-Regulation; D036781:Fimbriae Proteins / Q000494:pharmacology; D010861:Fimbriae, Bacterial / Q000502:physiology*; D006801:Humans; D008562:Membrane Glycoproteins / Q000502:physiology; D016328:NF-kappa B / Q000378:metabolism*; D016966:Porphyromonas gingivalis / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000502:physiology; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000494:pharmacology; D051193:Toll-Like Receptors; D051996:Transcription Factor RelA
chemical_list: D008562:Membrane Glycoproteins; D016328:NF-kappa B; D011956:Receptors, Cell Surface; D015375:Receptors, Interleukin-2; D011994:Recombinant Proteins; D051193:Toll-Like Receptors; D051996:Transcription Factor RelA; C063055:fimbrillin; D036781:Fimbriae Proteins; D004247:DNA