(ARG-GLY-ASP)N-ALBUMIN CONJUGATES AS A MODEL SUBSTRATUM FOR INTEGRIN-MEDIATED CELL-ADHESION
(ARG-GLY-ASP)N-ALBUMIN CONJUGATES AS A MODEL SUBSTRATUM FOR INTEGRIN-MEDIATED CELL-ADHESION
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DOI：
10.1016/0014-4827(89)90290-5
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发表时间：
1989-05-01
影响因子：
3.7
通讯作者：
JULIANO, RL
中科院分区：
文献类型：
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作者：
DANILOV, YN;JULIANO, RL
我们已经制备了蛋白质-肽缀合物组成的牛血清白蛋白（BSA）衍生的短肽含有Arg-Gly-Asp（RGD）序列来自纤维连接蛋白的粘附位点。将RGD-BSA缀合物用于涂覆组织培养塑料表面，然后将其用作细胞粘附实验中的基质。我们的研究结果表明，粘附到RGD-BSA包被的表面的效率是高度依赖于（RGD）n-BSA缀合物的化合价。例如，在具有大约等量的RGD配体的表面上，CHO细胞几乎100%粘附于（RGD）n-BSA（n = 20.8）缀合物，而根本不粘附于（RGD）n-BSA（n = 3.5）缀合物。粘附（RGD）n-BSA包被的基质和纤连蛋白或玻连蛋白包被的基质上也进行了检查，在细胞粘附和吸附的蛋白质的分子间距离之间的关系。有人观察到，对于基质包被相对紧凑，对称的分子，如RGD-BSA或玻连蛋白，粘附急剧下降，分子间距离的增加，相比之下，纤连蛋白，一个大的不对称分子，粘附下降更逐渐分子间距离的增加。最后，我们研究了不同的细胞表面受体在粘附RGD-BSA基质的过程中的作用。有趣的是，与抗体和可溶性竞争蛋白质的竞争和阻断实验表明，它是玻连蛋白受体，而不是纤连蛋白受体介导的粘附RGD-BSA。
We have prepared protein-peptide conjugates composed of bovine serum albumin (BSA) derivatized with short peptides containing the Arg-Gly-Asp (RGD) sequence derived from the adhesion site of fibronectin. The RGD-BSA conjugates were used to coat tissue culture plastic surfaces which then served as substrata in cell adhesion experiments. Our results indicate that the efficiency of adhesion to RGD-BSA-coated surfaces is highly dependent on the valency of the (RGD)n-BSA conjugates. For example, on surfaces with approximately equal amounts of RGD ligand, CHO cells adhered virtually 100% to the (RGD)n-BSA (n = 20.8) conjugate and not at all to the (RGD)n-BSA (n = 3.5) conjugate. Adhesion on (RGD)n-BSA-coated substrata and on fibronectin- or vitronectin-coated substrata was also examined in terms of the relationship between cell adhesion and the intermolecular distances of adsorbed proteins. It was observed that for substrata coated with relatively compact, symmetric molecules, such as RGD-BSA or vitronectin, adhesion dropped off sharply as intermolecular distances increased; by contrast, for fibronectin, a large asymmetric molecule, adhesion declined more gradually as intermolecular distances increased. Finally, we have examined the role of different cell-surface receptors in the process of adhesion to RGD-BSA substrata. Interestingly, competition and blocking experiments with antibodies and with soluble competing proteins suggest that it is the vitronectin receptor rather than the fibronectin receptor which mediates adhesion to RGD-BSA.