Susceptihility of human keratinocytes to ultraviolet B light

点击翻译按钮获取中文摘要

Susceptibility of human keratinocytes to ultraviolet B light (UVBL) was examined in order to understand the mechanisms of photosensitivity found in lupus erythematosus (LE) and other photosensitive diseases.1.Keratinocytes cultureCulture of human keratinocytes was established from patients with photosensitivity and from normal controls by using suction blister epidermal roof and serum-free keratinocyte growth medium.2.UVBL-induced cytotoxicity of keratinocytesUVBL induced cytotoxicity of cultured keratinocytes at the dose of 50 and 100 mJ/cm^2. The cytotoxicity was much higher in photosensitivity patients than normal controls. Apoptotic cell ratio was similar between patients and normal controls.3.UVBL-induced susceptibility of keratinocytesThe usefulness of expression of U1RNP and SS-A/Ro antigens was examined. These antigens were induced on the surface of UVBL-irradiated keratinocytes, which was confirmed by an immunofluorescence method and a confocal laser microscopy. Positive binding of antisera containing antibodies against U1RNP or SS-A/Ro was much higher in patients with photosensitivity than normal controls.4.Regulations of photosusceptibility by sunscreen and cytokinesUVBL-induced susceptibility was blocked by sunscreen, and upregulated by ETAF.These findings suggest that expression of U1RNP or SS-A/Ro antigens by UVBL was usefull for the detection of photosusceptibility as well as photosensitivity.