NF-kappaB activation in human dental pulp stem cells by TNF and LPS.
Post-natal human dental pulp stem cells (DPSCs) represent a unique precursor population in the dental pulp, which has multipotential and can regenerate a dentin/pulp-like structure. Because the dental pulp is frequently infected by oral bacteria due to dental decay, in this study, we examined whether lipopolysaccharide (LPS) and tumor necrosis factor (TNF) activated the immunologic transcription factor nuclear factor kappa B (NF-kappaB) in DPSCs. We found that both TNF and LPS activated the I-kappa B kinase complex (IKK) in DPSCs to induce the phosphorylation and degradation of IkappaBalpha, resulting in the nuclear translocation of NF-kappaB. Consistently, both TNF and LPS rapidly induced the expression of the NF-kappaB-dependent gene interleukin-8 (IL-8). However, unlike in monocytes, we found that LPS could not induce the phosphorylation of the NF-kappaB active subunit p65 in DPSCs. In summary, our studies suggest that DPSCs may be involved in immune responses during pulpal infection through activating NF-kappaB.
Chang
J
J
Laboratory of Molecular Signaling and Apoptosis, Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, 1011 N. University Ave., Ann Arbor, MI 48109-1078, USA.
Zhang
C
C
Tani-Ishii
N
N
Shi
S
S
Wang
C-Y
CY
D015152:Blotting, Northern; D015153:Blotting, Western; D002478:Cells, Cultured; D003782:Dental Pulp / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D024202:Electrophoretic Mobility Shift Assay; D020536:Enzyme Activators / Q000494:pharmacology; D006801:Humans; D051550:I-kappa B Kinase / Q000187:drug effects; D020672:I-kappa B Proteins / Q000187:drug effects; D016209:Interleukin-8 / Q000032:analysis; D008070:Lipopolysaccharides / Q000494:pharmacology; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000502:physiology*; D039902:Multipotent Stem Cells / Q000187:drug effects / Q000502:physiology*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects; D045202:Porphyromonas endodontalis; D016966:Porphyromonas gingivalis; D015398:Signal Transduction / Q000187:drug effects; D051996:Transcription Factor RelA / Q000187:drug effects; D015533:Transcriptional Activation / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D020536:Enzyme Activators; D020672:I-kappa B Proteins; D016209:Interleukin-8; D008070:Lipopolysaccharides; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha; D051550:I-kappa B Kinase