In vitro mechanism (s) of ultraviolet-induced tumor necrosis factor-alpha release in a human keratinocyte cell line
Corsini, E.; Bruccoleri, A.; Marinovich, M.; Galli, C.L.
Photodermatology Photoimmunology and Photomedicine 11(3): 112-118
1995
ISSN/ISBN: 0905-4383 PMID: 8555009 Document Number: 449089
It has been demonstrated that ultraviolet (UV) irradiation is able to induce both in vivo and in vitro, tumor necrosis factor-alpha (TNF) release. The purpose of the present study was to evaluate, using a human keratinocyte cell line NCTC 2544, the mechanism(s) of UV-induced TNF release and the ability of commonly used sunscreens to modulate UV-induced TNF release. TNF release can be partially prevented both by adding an anti-human IL-1-alpha antibody after irradiation, suggesting an autocrine effect of IL-1-alpha in inducing TNF release, and by adding antioxidants indicating also a role of oxidant species. TPCK, a I-kappa-B-alpha protease inhibitor, was able to virtually abolish UV-induced TNF release, indicating that UV-induced TNF release requires NF-kappa-B activation. Anti-human IL-1-beta antibody was ineffective as expected, considering that keratinocytes are unable to process pre-IL-1-beta to its active form. To evaluate the sunscreen's modulation on UV-induced TNF release, confluent cells were irradiated, in the presence or absence of the tested sunscreens (Uvinul MS40, Uvinul P25 and Uvinul DS49). Different IC-50 values could be calculated, which may be related to different UV absorption spectrums: Uvinul MS40 offers great protection by virtue of its broader absorption spectrum, closely followed by Uvinul P25 and finally by Uvinul DS49.