Roles of TLR2,TLR4,NOD2,and NOD1 in Pulp Fibroblasts

Abstract

Pulp fibroblasts express various pro-inflammatory mediators leading to marked infiltration of inflammatory cells in the progression of pulpitis. We hypothesized that pulp fibroblasts play roles in the recognition of invaded caries-related bacteria and the subsequent innate immune responses. We found clear expressions of TLR2, NOD1, and NOD2 and a faint expression of TLR4 in human dental pulp fibroblasts (HDPF) by RT-PCR and flow cytometry. We also observed that various pro-inflammatory mediators, including cytokines, chemokines, adhesion molecules, prostaglandin E₂ and its key enzyme COX-2, not iNOS or caspase-1, were markedly up-regulated by stimulation with these TLR and NOD agonists. More over, the NOD2 agonist acted synergistically with the TLR2, not the TLR4, agonist to stimulate the production of pro-inflammatory mediators in HDPF. These findings indicate that TLR2, TLR4, NOD2, and NOD1 in HDPF are functional receptors, and NOD2 is a modulator of signals transmitted through TLR2 in pulpal immune responses, leading to progressive pulpitis.

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References

Adachi T, Nakanishi T, Yumoto H, Hirao K, Takahashi K, Mukai K, et al. -2007-. Caries-related bacteria and cytokines induce CXCL10 in dental pulp. J Dent Res 86:1217–1222.

Bagis B, Atilla P, Cakar N, Hasanreisoglu U -2007-. Immunohistochemical evaluation of endothelial cell adhesion molecules in human dental pulp: effects of tooth preparation and adhesive application. Arch Oral Biol 52:705–711.

Chamaillard M, Hashimoto M, Horie Y, Masumoto J, Qiu S, Saab L, et al. -2003-. An essential role for NOD1 in host recognition of bacterial peptidoglycan containing diaminopimelic acid. Nat Immunol 4:702–707.

Di Nardo Di Maio F, Lohinai Z, D’Arcangelo C, De Fazio PE, Speranza L, De Lutiis MA, et al. -2004-. Nitric oxide synthase in healthy and inflamed human dental pulp. J Dent Res 83:312–316.

Fritz JH, Girardin SE, Fitting C, Werts C, Mengin-Lecreulx D, Caroff M, et al. -2005-. Synergistic stimulation of human monocytes and dendritic cells by Toll-like receptor 4 and NOD1- and NOD2-activating agonists. Eur J Immunol 35:2459–2470.

Girardin SE, Boneca IG, Carneiro LA, Antignac A, Jehanno M, Viala J, et al. -2003a-. Nod1 detects a unique muropeptide from Gram-negative bacterial peptidoglycan. Science 300:1584–1587.

Girardin SE, Boneca IG, Viala J, Chamaillard M, Labigne A, Thomas G, et al. -2003b-. Nod2 is a general sensor of peptidoglycan through muramyl dipeptide -MDP- detection. J Biol Chem 278:8869–8872.

Hahn CL, Liewehr FR -2007a-. Innate immune responses of the dental pulp to caries. J Endod 33:643–651.

Hahn CL, Liewehr FR -2007b-. Update on the adaptive immune responses of the dental pulp. J Endod 33:773–781.

10.

Hahn CL, Best AM, Tew JG -2000-. Cytokine induction by Streptococcus mutans and pulpal pathogenesis. Infect Immun 68:6785–6789.

11.

Hamilton IR -2000-. Ecological basis for dental caries. In: Oral bacterial ecology: the molecular basis. Kuramitsu HK, Ellen RP, editors. Wymondham, UK: Horizon Scientific Press, pp. 219–274.

12.

Huang GT, Potente AP, Kim JW, Chugal N, Zhang X -1999-. Increased interleukin-8 expression in inflamed human dental pulps. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 88:214–220.

13.

Inohara N, Ogura Y, Fontalba A, Gutierrez O, Pons F, Crespo J, et al. -2003-. Host recognition of bacterial muramyl dipeptide mediated through NOD2. Implications for Crohn’s disease. J Biol Chem 278:5509–5512.

14.

Izumi T, Kobayashi I, Okamura K, Sakai H -1995-. Immunohistochemical study on the immunocompetent cells of the pulp in human non-carious and carious teeth. Arch Oral Biol 40:609–614.

15.

Jiang HW, Zhang W, Ren BP, Zeng JF, Ling JQ -2006-. Expression of Toll like receptor 4 in normal human odontoblasts and dental pulp tissue. J Endod 32:747–751.

16.

Kawai T, Akira S -2006-. TLR signaling. Cell Death Differ 13:816–825.

17.

Lee JC, Yu MK, Lee R, Lee YH, Jeon JG, Lee MH, et al. -2008-. Terrein reduces pulpal inflammation in human dental pulp cells. J Endod 34:433–437.

18.

Martin FE, Nadkarni MA, Jacques NA, Hunter N -2002-. Quantitative microbiological study of human carious dentine by culture and real-time PCR: association of anaerobes with histopathological changes in chronic pulpitis. J Clin Microbiol 40:1698–1704.

19.

Matsushima K, Ohbayashi E, Takeuchi H, Hosoya S, Abiko Y, Yamazaki M -1998-. Stimulation of interleukin-6 production in human dental pulp cells by peptidoglycans from Lactobacillus casei. J Endod 24:252–255.

20.

Mutoh N, Tani-Ishii N, Tsukinoki K, Chieda K, Watanabe K -2007-. Expression of Toll-like receptor 2 and 4 in dental pulp. J Endod 33:1183–1186.

21.

Nagaoka S, Tokuda M, Sakuta T, Taketoshi Y, Tamura M, Takada H, et al. -1996-. Interleukin-8 gene expression by human dental pulp fibroblast in cultures stimulated with Prevotella intermedia lipopolysaccharide. J Endod 22:9–12.

22.

Nakanishi T, Matsuo T, Ebisu S -1995-. Quantitative analysis of immunoglobulins and inflammatory factors in human pulpal blood from exposed pulps. J Endod 21:131–136.

23.

Nakanishi T, Shimizu H, Hosokawa Y, Matsuo T -2001-. An immunohistological study on cyclooxygenase-2 in human dental pulp. J Endod 27:385–388.

24.

Nakanishi T, Takahashi K, Hosokawa Y, Adachi T, Nakae H, Matsuo T -2005-. Expression of macrophage inflammatory protein 3alpha in human inflamed dental pulp tissue. J Endod 31:84–87.

25.

Netea MG, Ferwerda G, de Jong DJ, Jansen T, Jacobs L, Kramer M, et al. -2005-. Nucleotide-binding oligomerization domain-2 modulates specific TLR pathways for the induction of cytokine release. J Immunol 174:6518–6523.

26.

Park SH, Hsiao GY, Huang GT -2004-. Role of substance P and calcitonin gene-related peptide in the regulation of interleukin-8 and monocyte chemotactic protein-1 expression in human dental pulp. Int Endod J 37:185–192.

27.

Smith WL, Dewitt DL -1996-. Prostaglandin endoperoxide H synthases-1 and -2. Adv Immunol 62:167–215.

28.

Staquet MJ, Durand SH, Colomb E, Romeas A, Vincent C, Bleicher F, et al. -2008-. Different roles of odontoblasts and fibroblasts in immunity. J Dent Res 87:256–261.

29.

Tada H, Aiba S, Shibata K, Ohteki T, Takada H -2005-. Synergistic effect of Nod1 and Nod2 agonists with Toll-like receptor agonists on human dendritic cells to generate interleukin-12 and T helper type 1 cells. Infect Immun 73:7967–7976.

30.

Takeda K, Akira S -2005-. Toll-like receptors in innate immunity. Int Immunol 17:1–14.

31.

Tokuda M, Sakuta T, Fushuku A, Torii M, Nagaoka S -2001-. Regulation of interleukin-6 expression in human dental pulp cell cultures stimulated with Prevotella intermedia lipopolysaccharide. J Endod 27:273–277.

32.

Tsai CH, Chen YJ, Huang FM, Su YF, Chang YC -2005-. The upregulation of matrix metalloproteinase-9 in inflamed human dental pulps. J Endod 31:860–862.

33.

Veerayutthwilai O, Byers MR, Pham TT, Darveau RP, Dale BA -2007-. Differential regulation of immune responses by odontoblasts. Oral Microbiol Immunol 22:5–13.

34.

Wang PL, Shirasu S, Daito M, Ohura K -2001-. Streptococcus mutans lipoteichoic acid-induced apoptosis in cultured dental pulp cells from human deciduous teeth. Biochem Biophys Res Commun 281:957–961.

35.

Williams TJ -1983-. Interactions between prostaglandins, leukotrienes and other mediators of inflammation. Br Med Bull 39:239–242.

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