Reichrath J, Münssinger T, Kerber A, Rochette-Egly C, Chambon P, Bahmer F A, Baum H P
Department of Dermatology, Universität des Saarlandes, Homburg, Germany.
Br J Dermatol. 1995 Aug;133(2):168-75. doi: 10.1111/j.1365-2133.1995.tb02612.x.
Increasing evidence suggests that the retinoid-X receptors RXR(-alpha,-beta,-gamma) play a crucial part in regulating the transcriptional activity of several steroid hormone receptors, including 1,25-dihydroxyvitamin D3 receptors (VDR) and retinoic acid receptors (RAR-alpha,-beta,-gamma). We developed a new technique for immunohistochemical in situ detection of RXR receptors, and investigated the localization of RXR-alpha in normal and psoriatic human skin using a recently raised corresponding specific antibody. RXR-alpha positive cells related to the skin were phenotyped by sequential sections and a double-labelling procedure for the simultaneous demonstration of this nuclear receptor and cell membrane antigens, as well as cytokeratin 10, HLA-DR and vimentin. Our findings indicate that: (i) RXR-alpha is strongly expressed in normal and psoriatic human skin; (ii) most of the cell types in normal human skin, including keratinocytes, melanocytes, fibroblasts and skin immune cells such as Langerhans cells, reveal strong nuclear immunoreactivity for RXR-alpha, with less cytoplasmic staining; (iii) altered levels or distribution of RXR-alpha in the skin do not appear to be involved in the genesis of psoriasis vulgaris, but subepidermal and subcellular distribution suggest a function of RXR-alpha in the transition from proliferation to differentiation in epidermal keratinocytes; (iv) expression in the hair follicle points to a contribution from RXR-alpha to hair growth.
越来越多的证据表明，维甲酸X受体RXR（-α、-β、-γ）在调节几种类固醇激素受体的转录活性中起关键作用，这些受体包括1,25-二羟维生素D3受体（VDR）和视黄酸受体（RAR-α、-β、-γ）。我们开发了一种免疫组织化学原位检测RXR受体的新技术，并使用最近制备的相应特异性抗体研究了RXR-α在正常和银屑病患者皮肤中的定位。通过连续切片和双重标记程序对与皮肤相关的RXR-α阳性细胞进行表型分析，以同时显示这种核受体和细胞膜抗原，以及细胞角蛋白10、HLA-DR和波形蛋白。我们的研究结果表明：（i）RXR-α在正常和银屑病患者皮肤中强烈表达；（ii）正常人类皮肤中的大多数细胞类型，包括角质形成细胞、黑素细胞、成纤维细胞和皮肤免疫细胞如朗格汉斯细胞，对RXR-α显示出强烈的核免疫反应性，胞质染色较少；（iii）皮肤中RXR-α水平或分布的改变似乎与寻常型银屑病的发生无关，但表皮下和亚细胞分布表明RXR-α在表皮角质形成细胞从增殖向分化的转变中起作用；（iv）在毛囊中的表达表明RXR-α对毛发生长有贡献。
