ULTRAVIOLET-B-INDUCED APOPTOSIS OF KERATINOCYTES - EVIDENCE FOR PARTIAL INVOLVEMENT OF TUMOR-NECROSIS-FACTOR-ALPHA IN THE FORMATION OF SUNBURN CELLS

被引：244

作者：

SCHWARZ, A ^{[1
]}

BHARDWAJ, R ^{[1
]}

ARAGANE, Y ^{[1
]}

MAHNKE, K ^{[1
]}

RIEMANN, H ^{[1
]}

METZE, D ^{[1
]}

LUGER, TA ^{[1
]}

SCHWARZ, T ^{[1
]}

机构：

[1] UNIV MUNSTER, DEPT DERMATOL, LUDWIG BOLTZMANN INST CELL BIOL & IMMUNOBIOL SKIN, D-48149 MUNSTER, GERMANY

来源：

JOURNAL OF INVESTIGATIVE DERMATOLOGY | 1995年 / 104卷 / 06期

关键词：

D O I：

10.1111/1523-1747.ep12606202

中图分类号：

R75 [皮肤病学与性病学];

学科分类号：

100206 ;

摘要：

Irradiation with ultraviolet (UV) B radiation results in the formation of apoptotic keratinocytes called sunburn cells. Recently, it was demonstrated that keratinocytes can release tumor necrosis factor-alpha (TNF-alpha), which is known to cause apoptosis in particular cells. In addition, it has been shown that UVB light induces the release of TNF-alpha by keratinocytes and that keratinocytes express the 55-kD receptor for TNF-alpha. Therefore, we investigated whether TNF-alpha is involved in UV-induced apoptosis of keratinocytes. Normal human keratinocytes and HaCaT cells were exposed to UVB light, and apoptosis was examined by nick translation evaluated by fluorescence-activated cell sorter analysis. UVB induced apoptosis in a dose-dependent manner, which was confirmed by electron microscopy. Addition of a polyclonal antibody directed against human TNF-alpha immediately after UVB exposure was able to reduce DNA fragmentation. However, it was not possible to rescue all cells from apoptosis. To prove whether TNF-alpha is also involved in vivo in UVB-induced apoptosis of keratinocytes, Balb/c mice were exposed to UVB on their abdomens, skin biopsies were performed 24 h later, and sunburn cells were counted. A single dose of 2000 J/m(2) caused a significant induction of sunburn cells. Subcutaneous injection of a polyclonal antibody directed against murine TNF-alpha immediately after UVB treatment resulted in a significant but incomplete reduction of sunburn cells, whereas injection of a rabbit IgG as a control had no effect. In both the in vitro and in vivo systems, application of recombinant TNF-alpha alone either to untreated keratinocytes or into normal murine skin did not induce sunburn cells. Thus, these data demonstrate that TNF-alpha is involved in UVB-induced apoptosis, but by itself is not able to induce sunburn cells. This further supports the notion that UVB-induced apoptosis of keratinocytes is a multifactorial event.

引用

页码：922 / 927

页数：6

共 34 条

[21] INDUCTION OF APOPTOTIC DNA-DAMAGE AND CELL-DEATH BY ACTIVATION OF THE SPHINGOMYELIN PATHWAY [J].