Scoazec J Y, Bringuier A F, Medina J F, Martínez-Ansó E, Veissiere D, Feldmann G, Housset C
INSERM U327, Faculté de Médecine Xavier Bichat, Université Paris 7, France.
J Hepatol. 1997 Mar;26(3):543-53. doi: 10.1016/s0168-8278(97)80419-9.
BACKGROUND/AIMS: In transporting epithelia, like the biliary epithelium, most plasma membrane proteins present a polarized distribution, essential for the maintenance of the structural and functional properties of the epithelium. We therefore analyzed the expression of polarized plasma membrane proteins by human biliary epithelial cells in order to compare them with other transporting epithelial cells and to search for differences in plasma membrane protein expression between their different anatomical subsets.
We designed an in situ immunohistochemical study of the various anatomical compartments of the human biliary tract in order to assess the pattern of expression of selected polarized plasma membrane proteins, including integrin receptors, ectopeptidases, membrane transporters and GPI-linked proteins.
All biliary epithelial cells expressed the same repertoire of integrins, except for integrin chain alpha5, restricted to the intra-hepatic compartments. All biliary epithelial cells expressed the following apical ectopeptidases: aminopeptidase-N, neutral-endopeptidase, dipeptidyl-peptidase IV. All biliary epithelial cells expressed the membrane transporter Na+ K+-ATPase, restricted to the basolateral domain, and the apical transporters CFTR and MDR-1. The apical AE2 anion exchanger was restricted to the small intra-hepatic bile ducts and the gallbladder. The GPI-linked protein protectin was basolateral in the intrahepatic bile ducts and apical in the gallbladder.
The structural organization of the plasma membrane of biliary epithelial cells is very similar to that of other simple epithelia and exhibits a limited degree of heterogeneity.
背景/目的：在诸如胆管上皮等转运上皮中，大多数质膜蛋白呈现极化分布，这对于维持上皮的结构和功能特性至关重要。因此，我们分析了人胆管上皮细胞极化质膜蛋白的表达，以便将它们与其他转运上皮细胞进行比较，并寻找其不同解剖亚群之间质膜蛋白表达的差异。
我们设计了一项对人胆道不同解剖区域的原位免疫组织化学研究，以评估所选极化质膜蛋白的表达模式，包括整合素受体、外肽酶、膜转运蛋白和糖基磷脂酰肌醇连接蛋白。
除整合素α5链仅限于肝内区域外，所有胆管上皮细胞表达相同的整合素种类。所有胆管上皮细胞均表达以下顶端外肽酶：氨肽酶-N、中性内肽酶、二肽基肽酶IV。所有胆管上皮细胞均表达膜转运蛋白钠钾ATP酶，其仅限于基底外侧结构域，以及顶端转运蛋白囊性纤维化跨膜传导调节因子（CFTR）和多药耐药蛋白1（MDR-1）。顶端阴离子交换蛋白AE2仅限于小的肝内胆管和胆囊。糖基磷脂酰肌醇连接蛋白保护素在肝内胆管中位于基底外侧，在胆囊中位于顶端。
胆管上皮细胞质膜的结构组织与其他单层上皮非常相似，并且表现出有限程度的异质性。
