Nakamura M, Rikimaru T, Yano T, Moore K G, Pula P J, Schofield B H, Dannenberg A M
Department of Environmental Health Sciences, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland.
J Invest Dermatol. 1990 Sep;95(3):325-32. doi: 10.1111/1523-1747.ep12485073.
This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36 degrees C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components. The toxicant type seemed to be caused by an invagination of the plasma membrane. Only toxicant-type vacuoles increased appreciably in number when skin explants were exposed to mustard, and to other toxicants.
本报告描述了一种用于测试局部应用于人体皮肤的化学物质毒性的模型器官培养系统。在该系统中，全层皮肤外植体中的活角质形成细胞受到与供体身上剩余皮肤相同的角质化层保护，并且可以通过显微镜和/或生化方法评估毒性。人体皮肤标本取自各种外科手术。将它们切成1.0平方厘米的全层外植体，并短暂暴露于用作模型毒物的军用糜烂剂硫芥（SM）中。然后将外植体在小培养皿中于36℃进行器官培养24小时。在0.03 - 1.0%的剂量范围内，所施加的SM浓度与表皮组织学上所见的核旁空泡数量之间呈现直线剂量反应关系。在相同的SM剂量范围内，外植体对14C - 亮氨酸的摄取也呈比例下降。因此，核旁空泡的数量反映了受损表皮细胞蛋白质合成的减少。未处理（对照）的全层人体皮肤外植体的表皮在4℃的培养基中储存时通常能存活7天。在储存期间，表皮内会形成相对少量的核旁空泡，但这些外植体仍非常适合用于测试SM毒性。将此类对照皮肤外植体在36℃孵育（4或24小时）可减少（通常减少50%）在储存4 - 7天期间产生的少量核旁空泡。这种减少可能是由许多空泡化细胞的自溶引起的。通过光学显微镜和电子显微镜均可识别出两种类型的核旁空泡：储存型和毒物型。储存型似乎是由细胞成分的自溶引起的。毒物型似乎是由质膜内陷引起的。当皮肤外植体暴露于芥子气和其他毒物时，只有毒物型空泡的数量明显增加。
