Isolation and characterization of laminin-10/11 secreted by human lung carcinoma cells -: Laminin-10/11 mediates cell adhesion through integrin α3β1
Isolation and characterization of laminin-10/11 secreted by human lung carcinoma cells -: Laminin-10/11 mediates cell adhesion through integrin α3β1
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DOI：
10.1074/jbc.273.25.15854
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发表时间：
1998-06-19
影响因子：
4.8
通讯作者：
Sekiguchi, K
中科院分区：
文献类型：
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作者：
Kikkawa, Y;Sanzen, N;Sekiguchi, K
筛选一组人肿瘤细胞系的层粘连蛋白α 5链的选择性表达，层粘连蛋白α 5链是一种新鉴定的层粘连蛋白亚基，包含层粘连蛋白-10（α 5 β 1 γ 1）和层粘连蛋白-11（α 5 β 2 γ 1）。发现肺腺癌细胞系A549以相对高的水平表达α 5链，但没有可检测量的其他α链。使用抗层粘连蛋白单克隆抗体4C 7，通过免疫亲和色谱法从A549细胞的条件培养基中纯化含有α 5链的层粘连蛋白变体，所述抗层粘连蛋白单克隆抗体4C 7最近显示识别层粘连蛋白α 5链（Tiger，C. F.、Chaud，M. F.、Pedrosa-Domellof，F.，索内尔湖E、Ekblom，P.，和Gullberg，D.（1997）J.Biol.Chem.272，28590-28595）。纯化的层粘连蛋白变体由分子量为350、220和210 kDa的三条链组成。350-kDa链被另一种能够在免疫印迹上识别变性α 5链的抗α 5链单克隆抗体特异性识别，而810-kDa链被抗γ 1链抗体识别。纯化的含α 5链的层粘连蛋白变体（此后称为层粘连蛋白-10/11）在介导A549细胞与基质的粘附中具有高度活性，其效力与层粘连蛋白-5的效力一样高，并且显著高于层粘连蛋白-1、层粘连蛋白-2/4或纤连蛋白的效力。针对整合素α 3或β 1亚基的抗整合素抗体特异性抑制层粘连蛋白-10/11包被基质的粘附，但不抑制α 2或α 6亚基的抗整合素抗体，表明层粘连蛋白-10/11被整合素α 3 β 1特异性识别。鉴于层粘连蛋白-10/11在各种组织类型的基底膜中的广泛分布和整合素α 3 β 1在大多数上皮细胞中的显性表达，层粘连蛋白-10/11与整合素α 3 β 1的特异性相互作用可能在通过基底膜的上皮细胞增殖和分化的体内调节中起重要作用。
A panel of human tumor cell lines was screened for selective expression of laminin alpha 5 chain, a newly identified laminin subunit comprising laminin-10 (alpha 5 beta 1 gamma 1) and -11 (alpha 5 beta 2 gamma 1). The lung adenocarcinoma cell line A549 was found to express the alpha 5 chain at relatively high levels but no detectable amounts of other alpha chains. The laminin variants containing alpha 5 chain were purified from the conditioned medium of A549 cells by immunoaffinity chromatography using the anti-laminin monoclonal antibody 4C7 which was shown recently to recognize the laminin alpha 5 chain (Tiger, C.-F., Champliaud, M.-F., Pedrosa-Domellof, F., Thornell, L.-E., Ekblom, P., and Gullberg, D. (1997) J. Biol. Chem. 272, 28590-28595). The purified laminin variants consisted of three chains with molecular masses of 350, 220, and 210 kDa. The 350-kDa chain was specifically recognized by another anti-alpha 5 chain monoclonal antibody capable of recognizing denatured alpha 5 chain on immunoblots, whereas the 810-kDa chain was recognized by an anti-gamma 1 chain antibody. The purified alpha 5 chain-containing laminin variants thereafter referred to as laminin-10/11) were highly active in mediating adhesion of A549 cells to the substratum with potency as high as that of laminin-5 and significantly higher than those of laminin-1, laminin-2/4, or fibronectin. Adhesion to substrata coated with laminin-10/11 was specifically inhibited by anti-integrin antibodies directed against the integrin alpha 3 or beta 1 subunit but not by those against alpha 2 or alpha 6 subunit, indicating that laminin-10/11 is specifically recognized by integrin alpha 3 beta 1. Given the wide distribution of laminin-10/11 in the basement membrane of various tissue types and dominant expression of integrin alpha 3 beta 1 in most epithelial cells, specific interaction of laminin-10/11 with integrin alpha 3 beta 1 may play an important role in in vivo regulation of proliferation and differentiation of epithelial cells through the basement membrane.