D'Errico J A, Sauk J J, Prince C W, Somerman M J
Department of Periodontics/Prevention/Geriatrics, University of Michigan, Ann Arbor 48109-1078, USA.
J Periodontal Res. 1995 Jan;30(1):34-41. doi: 10.1111/j.1600-0765.1995.tb01250.x.
Osteopontin (OPN) promotes attachment and spreading of cells in an RGD dependent fashion, suggesting that OPN interacts with integrins on cell surfaces. Here in, we show that LM-609, a monoclonal antibody to the alpha v beta 3 integrin (a vitronectin receptor), inhibited OPN-mediated attachment of gingival fibroblasts. To characterize the cell surface receptors responsible for this interaction, we performed OPN-sepharose affinity chromatography using detergent extracts of 35S-methionine or 125I-surface labeled gingival fibroblasts. Proteins bound to the OPN-matrix were eluted with EDTA and subjected to SDS-PAGE under reducing conditions. EDTA eluates from both 125I-surface labeled and 35S-methionine labeled extracts demonstrated prominent bands in the 90kDa and 50kDa regions, by both autoradiography and fluorography, respectively. These studies suggest that OPN is associated with other cell surface molecules in addition to alpha v beta 3. Furthermore, these as yet to be characterized proteins, may prove to have a stronger affinity for OPN than alpha v beta 3.
骨桥蛋白（OPN）以依赖RGD的方式促进细胞的黏附和铺展，这表明OPN与细胞表面的整合素相互作用。在此，我们发现LM-609，一种针对αvβ3整合素（一种玻连蛋白受体）的单克隆抗体，可抑制OPN介导的牙龈成纤维细胞黏附。为了鉴定负责这种相互作用的细胞表面受体，我们使用35S-甲硫氨酸或125I表面标记的牙龈成纤维细胞的去污剂提取物进行了OPN-琼脂糖亲和层析。与OPN基质结合的蛋白质用EDTA洗脱，并在还原条件下进行SDS-PAGE。来自125I表面标记和35S-甲硫氨酸标记提取物的EDTA洗脱物，分别通过放射自显影和荧光自显影，在90kDa和50kDa区域显示出明显的条带。这些研究表明，除了αvβ3之外，OPN还与其他细胞表面分子相关。此外，这些尚未鉴定的蛋白质，可能对OPN具有比αvβ3更强的亲和力。
