Carbohydrate-carbohydrate interaction in cell biology

描述（由申请人提供）：作为细胞粘附基础的碳水化合物-碳水化合物相互作用（CCI）的概念最初是在（i）我们对小鼠畸胎瘤F9细胞自聚集机制的研究（其模拟植入前胚胎的压实）和（ii）Max Burger及其小组对海绵细胞种属特异性自聚集的研究期间开发的。在过去的十年中，越来越多的各种结构已被发现参与无论是同型或异型CCI，发生在两个接口细胞的表面上的鞘糖脂（GSL）的集群。CCI已经被表面等离子体共振（SPR）光谱和原子力显微镜的先进技术很好地阐述，其结合亲和力与碳水化合物-蛋白质相互作用（CPI）和蛋白质-蛋白质相互作用（PPI）的结合亲和力在相同的范围内。CCI具有CPI或PPI所没有的独特功能。 建议研究的具体目标是：1。探索基于使用先前未测试的GSL和来自糖蛋白的PE缀合的N-连接或O-连接寡糖探针检测的新型CCI的新细胞粘附系统：（a）基于先前未测试的GSL结构的CCI;（B）基于N-连接或O-连接寡糖的CCI，其缀合至PE，组装为“糖基SAM”或“糖芯片”;（c）基于新发现的CCI的细胞粘附系统。 2.阐明并提供CCI作为生理学或病理学相关细胞粘附系统的初始步骤参与的证据，其中CCI被建议发生。（a）进一步研究小鼠畸胎瘤F9细胞自聚集中基于Lex-CCI和基于钙粘蛋白的PPI。 (b)其他细胞粘附系统：（i）接触抑制的角膜上皮细胞的基于Lex-based的细胞间粘附;（ii）人畸胎瘤细胞自聚集中的Gb 4-依赖性CCI;（iii）Ley-to-H相互作用介导人癌细胞与内皮细胞的粘附;（iv）基于GM 3-to-LacCer相互作用的黑色素瘤细胞与小鼠内皮细胞粘附的机制。 在项目1或2中观察到的通过CCI的细胞粘附将通过（i）排除碳水化合物结合蛋白的可能参与;（ii）RNAi方法的应用;（iii）新的SPR/“数字窗口”程序来证实。

DESCRIPTION (provided by applicant): The concept of carbohydrate-to-carbohydrate interaction (CCI) as a basis of cell adhesion was originally developed during (i) our studies on mechanism of autoaggregation of mouse teratocarcinoma F9 cells, which mimics compaction of pre-implantation embryo; and (ii) studies by Max Burger and his group on species-specific autoaggregation of marine sponge cells. During the past decade, an increasing variety of structures have been found to be involved in either homotypic or heterotypic CCI, occurring through clusters of glycosphingolipids (GSLs) at the surfaces of two interfacing cells. CCI has been well elaborated by advanced technology in surface plasmon resonance (SPR) spectroscopy and atomic force microscopy, and its binding affinity is in the same range as that of carbohydrate-to-protein interaction (CPI) and protein-to-protein interaction (PPI). CCI has unique features not found in CPI or PPI. The specific aims of the proposed studies are: 1. Explore new cell adhesion systems based on new types of CCI detected using previously untested GSLs, and PE-conjugated N-linked or O-linked oligosaccharide probes from glycoproteins: (a) CCI based on previously-untested GSL structures; (b) CCI based on N-linked or O-linked oligosaccharides, conjugated to PE, assembled as "glycosyl SAM" or "glycochip"; (c) cell adhesion system based on the newly-found CCI. 2. Elucidate and provide evidence for involvement of CCI as initial step in physiologically or pathobiologically relevant cell adhesion systems in which CCI is suggested to occur, (a) Further studies on Lex-based CCI and cadherin-based PPI in mouse teratocarcinoma F9 cell autoaggregation. (b) Other cell adhesion systems: (i) Lex-based cell-to-cell adhesion of contact-inhibited corneal epithelial cells; (ii) Gb4-dependent CCI in autoaggregation of human teratocarcinoma cells; (iii) Ley-to-H interaction mediating adhesion of human cancer cells to endothelial cells; (iv) Mechanism of melanoma cell adhesion to mouse endothelial cells, based on GM3-to-LacCer interaction. Cell adhesion through CCI observed in Project 1 or 2 will be confirmed by (i) ruling out possible involvement of carbohydrate-binding protein; (ii) application of RNAi approach; (iii) a new SPR/ "digital window" procedure.