Toll-like receptor 2 mediates a cutaneous reaction induced by repetitive ultraviolet B irradiation in C57/BL6 mice in vivo.

Abstract

Toll-like receptors (TLRs) mediate not only innate immunity against infection and but also sterile inflammation triggered by endogenous molecules. We conducted a comparative study of the different inflammatory responses induced by repetitive ultraviolet (UV) B irradiation in wild-type (WT) and TLR2 knockout (KO) mice, to provide in vivo evidence of the role of TLRs in mediating UVB-induced responses. UVB-induced inflammatory responses were less severe in TLR2 KO mice than in WT mice after 6 weeks of repeated UVB irradiation. UVB-treated TLR2 KO mice displayed less prominent erythema and scaling, and histopathology showed significantly thinner skin and less inflammatory cell infiltration than that in WT mice. UVB-induced expression of heat-shock protein 70 (an endogenous ligand of TLR2) was lower in TLR2 KO mice. Quantitative RT-PCR revealed significantly lower gene expression levels of UVB-induced interleukin (IL)-1β, IL-6 and matrix metalloproteinase (MMP)-13 in TLR2 KO mice. TLR2 KO mice also showed significantly lower protein level expression of UVB-induced IL-1β in ELISA and MMP-13 in Western blots. Our study demonstrated that TLR2 was associated with inflammatory responses to repetitive UVB irradiation in C57/BL6 mice. Moreover, it suggests that the role of TLR2 in the cutaneous response of UV irradiation and in developing new agents for modulating the effects of UV irradiation should be considered.

• Authors: Hyun Sun Park, Seon Pil Jin, Youngae Lee, In Gyung Oh, Serah Lee, Jung Ho Kim, Kwang Hyun Cho, Jin Ho Chung
• Journal: Experimental dermatology (Exp Dermatol) Vol. 23 Issue 8 Pg. 591-5 (Aug 2014) ISSN: 1600-0625 [Electronic] Denmark
• PMID: 24962024 (Publication Type: Comparative Study, Journal Article)
• Copyright: © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Chemical References

• HSP70 Heat-Shock Proteins
• Interleukin-1beta
• Interleukin-6
• Tlr2 protein, mouse
• Toll-Like Receptor 2
• Matrix Metalloproteinase 13

Topics

• Animals
• Disease Models, Animal
• Dose-Response Relationship, Radiation
• HSP70 Heat-Shock Proteins (metabolism)
• Inflammation (etiology, metabolism, pathology)
• Interleukin-1beta (metabolism)
• Interleukin-6 (metabolism)
• Matrix Metalloproteinase 13 (metabolism)
• Mice
• Mice, Inbred C57BL
• Mice, Knockout
• Skin (metabolism, pathology, radiation effects)
• Toll-Like Receptor 2 (deficiency, genetics, metabolism)
• Ultraviolet Rays (adverse effects)