First Author | Amerio P | Year | 2001 |
Journal | Br J Dermatol | Volume | 144 |
Issue | 5 | Pages | 952-7 |
PubMed ID | 11359380 | Mgi Jnum | J:103298 |
Mgi Id | MGI:3609097 | Doi | 10.1046/j.1365-2133.2001.04181.x |
Citation | Amerio P, et al. (2001) Rethinking the role of tumour necrosis factor-alpha in ultraviolet (UV) B-induced immunosuppression: altered immune response in UV-irradiated TNFR1R2 gene-targeted mutant mice. Br J Dermatol 144(5):952-7 |
abstractText | BACKGROUND: Ultraviolet (UV) B-induced immunosuppression, implicated in the pathogenesis of skin cancers, is postulated to be mediated in part by cis-urocanic acid (cis-UCA) via tumour necrosis factor (TNF)-alpha. TNF-alpha produces morphological changes in Langerhans cells indistinguishable from those induced by UVB exposure and antibodies against TNF-alpha have been demonstrated to inhibit UVB-induced immunosuppression in vivo. OBJECTIVES: To clarify further the role of TNF-alpha in UVB-induced immunosuppression and in cis-UCA immunosuppression. METHODS: We performed a contact hypersensitivity (CHS) assay on gene-targeted mutant mice (TNFR1R2-/-) lacking genes for both receptors (p55 and p75) for TNF-alpha. Mice were either irradiated with UVB or injected intradermally with cis-UCA, sensitized with 2,4-dinitrofluorobenzene, challenged on the ears and the response was measured. RESULTS: The TNFR1R2-/- mice showed hyporesponsiveness in the CHS response compared with wild-type (P < 0.001), confirming the proinflammatory role of TNF-alpha. However, significant suppression of CHS was seen after irradiation and after cis-UCA injection in both locally (sensitization on irradiated site; P < 0.05) and systemically (sensitization on non-irradiated site; P < 0.05) sensitized wild-type and gene-targeted mice. CONCLUSIONS: These results demonstrate that TNF-alpha signalling is only partially involved in UVB-induced immunosuppression and does not play a major part in the cis-UCA immunosuppression mechanism. |