Alkemade H, van de Kerkhof P, Schalkwijk J
Department of Dermatology, Academic Hospital Nijmegen, The Netherlands.
J Invest Dermatol. 1992 Jul;99(1):3-7. doi: 10.1111/1523-1747.ep12611375.
Recently we described a new elastase inhibitor (skin-derived antileukoproteinase, SKALP) that is expressed in psoriatic epidermis and cultured keratinocytes, but is virtually absent in normal skin. In this study we investigated whether SKALP activity could be measured in urine of psoriatic patients and healthy controls. We found that urine of psoriatic patients contained considerable amounts of anti-elastase activity, whereas this activity in urine from normals was significantly lower. The properties of the urinary anti-elastase activity in psoriatic patients were indistinguishable from that of epidermal SKALP. It was found to be a cationic, heat-stable protein with an apparent molecular weight of 11 kDa on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and a K(i) of approximately 2 x 10(-11) M. In addition, in Western blotting partially purified inhibitor from urine was found to react with a polyclonal anti-SKALP serum. SKALP in urine was either present in a free form or in a latent form, most likely complexed with elastase. We speculate that SKALP in urine of psoriatic patients is derived from the epidermis, and that it might serve as a marker for disease activity.
最近，我们描述了一种新的弹性蛋白酶抑制剂（皮肤衍生抗白细胞蛋白酶，SKALP），它在银屑病表皮和培养的角质形成细胞中表达，但在正常皮肤中几乎不存在。在本研究中，我们调查了是否可以在银屑病患者和健康对照者的尿液中检测到SKALP活性。我们发现，银屑病患者的尿液中含有大量的抗弹性蛋白酶活性，而正常人尿液中的这种活性则显著较低。银屑病患者尿液中抗弹性蛋白酶活性的特性与表皮SKALP的特性无法区分。它被发现是一种阳离子、热稳定的蛋白质，在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）上的表观分子量为11 kDa，K(i)约为2×10(-11)M。此外，在蛋白质印迹法中，从尿液中部分纯化的抑制剂被发现与多克隆抗SKALP血清发生反应。尿液中的SKALP要么以游离形式存在，要么以潜在形式存在，很可能与弹性蛋白酶结合。我们推测，银屑病患者尿液中的SKALP来自表皮，它可能作为疾病活动的一个标志物。
