Ruby J C, Halliday G M, Muller H K
Department of Pathology, University of Tasmania, Hobart, Australia.
J Invest Dermatol. 1989 Feb;92(2):150-5. doi: 10.1111/1523-1747.ep12276661.
The exposure of murine skin to potent chemical carcinogens induced distinctive effects on the distribution of epidermal Langerhans cells (LC). Our previous finding that weekly applications of 7,12-dimethylbenz[a]anthracene deplete the numbers of adenosine triphosphatase (ATPase)-positive LC was extended to show that LC are also depleted on Ia and beta-glucuronidase staining. In contrast, application of the tobacco-derived carcinogen, benzo[a]pyrene (BP), caused a significant increase in Ia-positive LC density within 2 weeks and elevated levels were maintained for up to 6 months with continuous treatment. The tobacco-derived cocarcinogenic agent, catechol, also enhanced the numbers of epidermal LC. The LC in carcinogen treated epidermis were morphologically abnormal; after BP and catechol treatment LC appeared smaller with shorter dendrites, whereas in DMBA treated epidermis LC were enlarged with elongated dendrites. Application of the contact sensitizing agent, dinitrofluorobenzene, to skin treated with BP induced hyporesponsiveness rather than contact sensitivity upon subsequent antigen challenge. Hence, the function of the large number of morphologically altered LC in BP treated skin was impaired. We conclude that carcinogen-induced alterations of LC are associated with impaired immunocompetence, although different carcinogens probably operate via different mechanisms to induce such phenomena.
将小鼠皮肤暴露于强效化学致癌物会对表皮朗格汉斯细胞（LC）的分布产生显著影响。我们之前的研究发现，每周应用7,12-二甲基苯并[a]蒽会使三磷酸腺苷酶（ATPase）阳性的LC数量减少，本研究进一步发现，LC在Ia和β-葡萄糖醛酸酶染色时也会减少。相比之下，应用烟草衍生的致癌物苯并[a]芘（BP）在2周内会使Ia阳性LC密度显著增加，持续治疗时，升高的水平可维持长达6个月。烟草衍生的辅助致癌物邻苯二酚也会增加表皮LC的数量。致癌物处理后的表皮中的LC形态异常；BP和邻苯二酚处理后，LC看起来更小，树突更短，而在二甲基苯并蒽（DMBA）处理的表皮中，LC更大，树突更长。将接触致敏剂二硝基氟苯应用于经BP处理的皮肤，在随后的抗原刺激时会诱导低反应性而非接触敏感性。因此，BP处理的皮肤中大量形态改变的LC的功能受损。我们得出结论，致癌物诱导的LC改变与免疫能力受损有关，尽管不同的致癌物可能通过不同的机制诱导这种现象。
