A novel recognition site on laminin for the alpha 3 beta 1 integrin.
A novel recognition site on laminin for the alpha 3 beta 1 integrin.
复制标题
层粘连蛋白上 α 3 β 1 整合素的新识别位点。
DOI：
10.1006/excr.1996.0036
复制
发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Skubitz,AP
中科院分区：
文献类型：
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作者：
Pattaramalai,S;Skubitz,KM;Skubitz,AP
合成肽GD-2是由层粘连蛋白A链的羧基末端长臂衍生的一系列氨基酸。以前的研究表明，多肽GD-2促进人鳞状细胞癌(SCC)细胞以及其他多种细胞系的黏附。在这项研究中，我们试图确定SCC细胞用来粘附肽GD-2的受体。制备了抗人SCC细胞系的单抗。其中一种单抗，ASC-1，通过流式细胞仪检测，结合到SCC细胞的表面。该单抗可抑制SCC细胞与多肽GD-2和层粘连蛋白的黏附，但不能抑制纤维连接蛋白或IV型胶原的黏附，提示单抗ASC-1与SCC受体结合的是多肽GD-2的层粘连蛋白。单抗ASC-1免疫共沉淀物由135 kDa和116 kDa两个组分组成。通过与单抗Asc-1孵育，从鳞癌细胞提取液中免疫吸附Asc-1结合物质，导致从提取液中去除α3β1整合素。对正常人和舌鳞癌患者的舌组织进行免疫组织化学染色，发现单抗ASC-1染色于接触基底膜的上皮细胞表面，以及位于基底膜上方2~3层的上皮细胞表面。该单抗还对鳞状组织中的血管进行了染色。这种染色模式与用抗α3整合素亚基的单抗对同一组织进行染色时观察到的一致。总之，通过使用一种识别α3β1整合素的新单抗Asc-1，我们已经确定α3β1整合素介导了鳞癌细胞与层粘连蛋白中的GD-2序列的黏附。
Synthetic peptide GD-2 is a sequence of amino acids derived from the carboxy-terminal long arm of the A chain of laminin. Previous studies have shown that peptide GD-2 promotes the adhesion of human squamous cell carcinoma (SCC) cells as well as a variety of other cell lines. In this study, we attempted to identify the receptor that SCC cells use to adhere to peptide GD-2. Monoclonal antibodies (mAbs) against a human SCC cell line were generated. One of these mAbs, ASC-1, bound to the surface of SCC cells as determined by flow cytometry. This mAb inhibited SCC cell adhesion to peptide GD-2 and laminin, but not fibronectin or type IV collagen, suggesting that mAb ASC-1 binds to the SCC receptor for the peptide GD-2 sequence of laminin. MAb ASC-1 immunoprecipitated a complex composed of two components of 135 and 116 kDa. Immunoadsorption of ASC-1-binding material from the SCC cell extract by incubation with mAb ASC-1 resulted in the removal of the α3β1 integrin from the extract. Immunohistochemical staining of tissue from a normal human tongue and from a patient with SCC of the tongue revealed that mAb ASC-1 stained the surface of epithelial cells that were in contact with the basement membrane, as well as those cells located two to three layers above the basement membrane. This mAb also stained blood vessels in the squamous tissue. This staining pattern was identical to that observed when the same tissues were stained by a mAb against the α3 integrin subunit. In summary, by use of a new mAb, ASC-1, that recognizes the α3β1 integrin, we have determined that the α3β1 integrin mediates SCC cell adhesion to the peptide GD-2 sequence within laminin.