Gruner S, Diezel W, Strunk D, Eckert R, Siems W, Anhalt G J
Department of Dermatology, Humboldt University, Berlin, Germany.
J Invest Dermatol. 1991 Sep;97(3):478-82. doi: 10.1111/1523-1747.ep12481515.
Lanthanides are rare earths, elements 55-71 in the periodic table, that are of interest in biologic systems as isomorphic competitors for calcium binding sites. Lanthanides were tested for their inhibitory influence on the Ca++/Mg(++)-dependent ATPase of epidermal langerhans cells in vitro, and on the immunologic function of Langerhans cells in vivo. The trivalent ions of lanthanides, lanthanum, and cerium completely inhibited the ATPase staining of Langerhans cells in vitro. When mice were sensitized with dinitrofluorobenzene on skin sites pretreated with topical lanthanum chloride, and challenged on untreated ear skin, a markedly reduced contact hypersensitivity response was observed. This hyporesponsiveness was found to be antigen specific, and could be passively transferred to naive syngeneic animals recipients by CD4-CD8+ spleen cells. These results suggest that inhibition of the epidermal Langerhans cell surface ATPase by application of topical lanthanum and the induction of antigen-specific immunologic tolerance may be related events.
镧系元素是稀土元素，即元素周期表中的55 - 71号元素，作为钙结合位点的同构竞争者，它们在生物系统中备受关注。研究人员测试了镧系元素对体外表皮朗格汉斯细胞的Ca++/Mg(++)依赖性ATP酶以及体内朗格汉斯细胞免疫功能的抑制作用。镧系元素的三价离子镧和铈在体外完全抑制了朗格汉斯细胞的ATP酶染色。当用局部氯化镧预处理皮肤部位后，再用二硝基氟苯致敏小鼠，并在未处理的耳部皮肤进行激发，观察到接触性超敏反应明显降低。发现这种低反应性具有抗原特异性，并且可以通过CD4 - CD8 +脾细胞被动转移给同基因的未致敏动物受体。这些结果表明，局部应用镧抑制表皮朗格汉斯细胞表面ATP酶与诱导抗原特异性免疫耐受可能是相关事件。
