Berkers J A, Hassing G A, Brouwer A, Blaauboer B J
Research Institute of Toxicology, Utrecht University, PO Box 80.176, NL-3508 TD Utrecht The Netherlands.
Toxicol In Vitro. 1994 Aug;8(4):605-8. doi: 10.1016/0887-2333(94)90027-2.
In order to study the interactive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), polychlorinated dibenzofurans (PCDFs) and retinoic acid on terminal differentiation of primary cultured keratinocytes derived from human foreskins, the amount of [(35)S]methionine-labelled proteins incorporated into cross-linked envelopes (CLEs) was determined. After isolation of the CLEs with sodium dodecyl sulfate, the amount of radioactivity collected on a filter was considered as a quantitative parameter for keratinocyte differentiation. Treatment of keratinocytes with different concentrations of TCDD resulted in a dose-dependent increase in differentiation, while only a minor decrease in differentiation occurred after treatment with retinoic acid. However, simultaneous application of 10(-8)m TCDD and different concentrations of retinoic acid led to a dose-dependent decrease in CLE formation. PCDFs exerted an effect on CLE formation similar to that of TCDD but with different potencies. We conclude that (1) TCDD induces a dose-dependent induction of human keratinocyte differentiation, (2) retinoic acid is a potent antagonist of TCDD-induced keratinocyte differentiation, and (3) primary cultures of human keratinocytes can serve as a useful model system to study the interactive effects of xenobiotics and hormone-like substances on the regulation of differentiation.
为了研究2,3,7,8-四氯二苯并-对-二恶英（TCDD）、多氯二苯并呋喃（PCDFs）和视黄酸对源自人包皮的原代培养角质形成细胞终末分化的交互作用，测定了掺入交联包膜（CLEs）中的[³⁵S]甲硫氨酸标记蛋白的量。在用十二烷基硫酸钠分离CLEs后，滤膜上收集的放射性量被视为角质形成细胞分化的定量参数。用不同浓度的TCDD处理角质形成细胞导致分化呈剂量依赖性增加，而用视黄酸处理后仅出现轻微的分化降低。然而，同时应用10⁻⁸m TCDD和不同浓度的视黄酸导致CLE形成呈剂量依赖性降低。PCDFs对CLE形成的影响与TCDD类似，但效力不同。我们得出结论：（1）TCDD诱导人角质形成细胞分化呈剂量依赖性；（2）视黄酸是TCDD诱导的角质形成细胞分化的有效拮抗剂；（3）人角质形成细胞的原代培养可作为研究外源性物质和类激素物质对分化调节的交互作用的有用模型系统。
