Welzel J, Metker C, Wolff H H, Wilhelm K P
Klinik für Dermatologie und Venerologie, Medizinische Universität zu Lübeck, Germany.
Arch Dermatol Res. 1998 Nov;290(11):615-20. doi: 10.1007/s004030050361.
It is well known that cutaneous irritants influence epidermal proliferation but the pathogenesis is poorly understood. Recent investigations have shown that the skin barrier integrity influences the proliferation of the basal keratinocytes. Our question was whether the proliferating activity of keratinocytes is indeed regulated by the degree of skin barrier damage or by a direct toxic action of the irritant on the keratinocytes. Therefore various degrees of skin irritation were induced by the application of 0.1%, 0.5% and 2% sodium lauryl sulphate (SLS) solution to the forearm skin of six healthy volunteers. This experiment was performed to evaluate the relationship between SLS concentration and epidermal proliferation. In a second experiment another 14 volunteers were treated with a single SLS concentration (0.5%) to look for interindividual differences in the patterns of skin reaction and susceptibility to the irritant. Skin barrier function was evaluated by measurements of transepidermal water loss (TEWL) before and after irritation. Punch biopsies were taken after 96 h from exposed areas and from unexposed normal skin. Dividing keratinocytes were identified immunocytochemically using three different monoclonal antibodies: PCNA, MIB 1 and KiS1. Exposure to SLS resulted in concentration-dependent increases in both TEWL and epidermal proliferation. However, no significant correlation could be found between the degree of hyperproliferation and the TEWL changes. The results suggest that epidermal proliferation is modulated by a direct interaction of the surfactant with the keratinocytes and/or by release of mediators rather than the consequence of a barrier disturbance.
众所周知，皮肤刺激物会影响表皮增殖，但发病机制尚不清楚。最近的研究表明，皮肤屏障完整性会影响基底角质形成细胞的增殖。我们的问题是，角质形成细胞的增殖活性究竟是受皮肤屏障损伤程度的调节，还是受刺激物对角质形成细胞的直接毒性作用的调节。因此，通过向6名健康志愿者的前臂皮肤涂抹0.1%、0.5%和2%的十二烷基硫酸钠（SLS）溶液，诱导出不同程度的皮肤刺激。进行该实验是为了评估SLS浓度与表皮增殖之间的关系。在第二个实验中，另外14名志愿者用单一浓度的SLS（0.5%）进行治疗，以寻找皮肤反应模式和对刺激物易感性的个体差异。通过测量刺激前后的经表皮水分流失（TEWL）来评估皮肤屏障功能。96小时后，从暴露区域和未暴露的正常皮肤处取冲孔活检组织。使用三种不同的单克隆抗体：增殖细胞核抗原（PCNA）、MIB 1和KiS1，通过免疫细胞化学方法鉴定正在分裂的角质形成细胞。暴露于SLS导致TEWL和表皮增殖均呈浓度依赖性增加。然而，在增殖过度程度与TEWL变化之间未发现显著相关性。结果表明，表皮增殖是由表面活性剂与角质形成细胞的直接相互作用和/或介质释放所调节，而不是屏障紊乱的结果。
