Debbage P L, Gabius H J, Bise K, Marguth F
Department of Anatomy, University of München/Federal Republic of Germany.
Eur J Cell Biol. 1988 Aug;46(3):425-34.
Protein-carbohydrate interactions are supposed to play a pivotal role in mediation of recognitive interactions, relevant to cellular interactions and transport. The brain microvasculature is the site of numerous cell-cell and cell-matrix recognitive interactions. Assuming carbohydrate-protein interactions play important physiological roles here, then specific carbohydrate-binding proteins should be prominent components of this microvasculature, in addition to the wealth of endogenous glycoconjugates reported by other authors. Human brain and brain tumor microvessels were analyzed histochemically for expression of endogenous sugar-binding proteins using a panel of biotin-conjugated, chemically glycosylated probes with specificities for alpha-/beta-D-galactosides and -D-glucosides, alpha-L-fucosides, alpha-D-mannosides, and beta-D-xylosides, and for expression of endogenous glycoconjugates using a panel of biotin-conjugated plant lectins with specificities for fucoside, galactoside, mannoside and glucoside moieties. Wax-embedded aldehyde- or Bouin-fixed tissues or acetone-fixed frozen sections were examined. Blood-brain barrier function was checked by ascertaining immunohistochemically the extravasation of serum albumin in these tissues. Microvessels in normal human brain tissues (with intact blood-brain barrier) contained abundant endogenous sugar-binding proteins with specificities for beta-galactosides, alpha-mannosides and beta-xylosides, and lesser amounts of proteins binding alpha-galactosides, alpha-fucosides and glucosides. Endogenous glycoconjugates bearing beta-galactoside, alpha-D-mannoside/alpha-D-glucoside or alpha-L-fucoside moieties were also abundant. In brain tumors (with defective blood brain barrier) the microvessels contained altered patterns of endogenous sugar-binding proteins, particularly noticeable in glioblastomas, in which there were notable alterations in galactoside-binding proteins in the microvessels.
蛋白质 - 碳水化合物相互作用被认为在介导与细胞相互作用和运输相关的识别性相互作用中起关键作用。脑微血管是众多细胞 - 细胞和细胞 - 基质识别性相互作用的场所。假设碳水化合物 - 蛋白质相互作用在此处发挥重要的生理作用，那么除了其他作者报道的大量内源性糖缀合物外，特定的碳水化合物结合蛋白应该是这种微血管的主要成分。使用一组对α-/β-D-半乳糖苷和-D-葡萄糖苷、α-L-岩藻糖苷、α-D-甘露糖苷和β-D-木糖苷具有特异性的生物素偶联化学糖基化探针，对人脑和脑肿瘤微血管进行组织化学分析，以检测内源性糖结合蛋白的表达，并使用一组对岩藻糖苷、半乳糖苷、甘露糖苷和葡萄糖苷部分具有特异性的生物素偶联植物凝集素，检测内源性糖缀合物的表达。检查了蜡包埋的醛固定或Bouin固定组织或丙酮固定的冰冻切片。通过免疫组织化学确定这些组织中血清白蛋白的外渗来检查血脑屏障功能。正常人脑组织（血脑屏障完整）中的微血管含有丰富的对内源性糖结合蛋白，这些蛋白对β-半乳糖苷、α-甘露糖苷和β-木糖苷具有特异性，而结合α-半乳糖苷、α-岩藻糖苷和葡萄糖苷的蛋白含量较少。带有β-半乳糖苷、α-D-甘露糖苷/α-D-葡萄糖苷或α-L-岩藻糖苷部分的内源性糖缀合物也很丰富。在脑肿瘤（血脑屏障有缺陷）中，微血管中内源性糖结合蛋白的模式发生了改变，在胶质母细胞瘤中尤为明显，其中微血管中半乳糖苷结合蛋白有显著变化。
