Cell surface glycoconjugates and adhesion molecules

细胞识别参与肿瘤细胞的炎症、组织重组、血管损伤、血管生成和转移等多种病理过程，是通过糖蛋白相互作用介导的。为了了解这些过程，必须阐明细胞表面糖结合物和凝集素的结构和功能。本课题主要针对以下几个方面进行了研究：(1)巨噬细胞半乳糖/N-乙酰半乳糖胺特异性凝集素的结构与功能研究。我们认为，该凝集素对TN抗原的糖特异性和高度支化的N-连接碳水化合物链适合于区分肿瘤细胞表面和非恶性细胞表面。(2)我们发现与丝氨酸和/或苏氨酸相连的sialyl-Le^x碳水化合物链参与了血小板诱导的超氧阴离子的产生。(3)纯化了一个参与N-乙酰乳糖胺型糖链形成的N-乙酰氨基葡萄糖基转移酶。

The cellular recognition involved in a variety of pathological processes such as, inflammation, tissue reorganization, vascular injury, angiogenesis, and metastasis of tumor cells is mediated by carbohydrate-protein interactions. To understand these processes, the structure and the function of cell surface glycoconjugates and lectins should be elucidated. In the present project, we focused on the following specific aims and made interesting observasions : (1)The structure and the function of macrophage galactose/N-acetylgalactosamine-specific lectins. We concluded that the carbohydrate specificity of this lectin towards Tn-antigen and highly branched N-linked carbohydrate chains were suitable to distinguish tumor cell surfaces from non-malignant cell surfaces. (2)We found that sialyl-Le^x carbohydrate chains linked to serine and/or threonine were responsible for the platelet-induced superoxide anion production. (3) We purified an N-acetylglucosaminyltransferase involved in the formation of poly-N-acetyllactosamine-type carbohydrate chains.