Functional TLRs and NODs in human gingival fibroblasts.
Since human gingival fibroblasts are the major cells in periodontal tissues, we hypothesized that gingival fibroblasts are endowed with receptors for bacterial components, which induce innate immune responses against invading bacteria. We found clear mRNA expression of Toll-like receptors (TLR)1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, MD-2, MyD88, NOD1, and NOD2 in gingival fibroblasts. Gingival fibroblasts constitutively expressed these molecules. Upon stimulation with chemically synthesized ligands mimicking microbial products for these receptors, the production of pro-inflammatory cytokines, such as interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1, was markedly up-regulated. Furthermore, the production of pro-inflammatory cytokines induced by TLR and NOD ligands was significantly inhibited by an RNA interference assay targeted to NF-kappaB. These findings indicate that these innate immunity-related molecules in gingival fibroblasts are functional receptors involved in inflammatory reactions in periodontal tissues, which might be responsible for periodontal pathogenesis.
Uehara
A
A
Department of Microbiology and Immunology, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Takada
H
H
D001426:Bacterial Proteins / Q000494:pharmacology; D002478:Cells, Cultured; D002648:Child; D016207:Cytokines / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D005347:Fibroblasts / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D005434:Flow Cytometry; D005881:Gingiva / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate / Q000502:physiology*; D018836:Inflammation Mediators / Q000378:metabolism; D051218:Lymphocyte Antigen 96 / Q000096:biosynthesis / Q000276:immunology; D053594:Myeloid Differentiation Factor 88 / Q000096:biosynthesis / Q000276:immunology; D016328:NF-kappa B / Q000187:drug effects; D053472:Nod Signaling Adaptor Proteins / Q000096:biosynthesis* / Q000276:immunology; D016133:Polymerase Chain Reaction; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis; D034741:RNA, Small Interfering / Q000494:pharmacology; D051193:Toll-Like Receptors / Q000096:biosynthesis* / Q000276:immunology
D001426:Bacterial Proteins; D016207:Cytokines; D018836:Inflammation Mediators; C495377:LY96 protein, human; D051218:Lymphocyte Antigen 96; C507779:MYD88 protein, human; D053594:Myeloid Differentiation Factor 88; D016328:NF-kappa B; D053472:Nod Signaling Adaptor Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D051193:Toll-Like Receptors