Kapila Y L, Lancero H, Johnson P W
Department of Stomatology, School of Dentistry, University of California San Francisco, 94143-0512, USA.
J Periodontol. 1998 Sep;69(9):1008-19. doi: 10.1902/jop.1998.69.9.1008.
Fibronectin (fn) is an extracellular matrix (ECM) molecule important in cell adhesion and migration and in wound healing. It is also likely important in periodontal ligament (PDL) cell-ECM interactions, and thus in regenerating periodontal tissues. In this study we characterized PDL cells and their interactions with FN, testing different PDL cell isolates taken from healthy and diseased conditions. PDL cells were characterized by their morphology, integrin profile, motility, and bone nodule formation. Cells were then assayed for adhesion, proliferation, and chemotaxis in response to FN or FN fragments. Cell isolates were morphologically heterogeneous and fibroblastic, had a normal-appearing actin cytoskeleton and a wide range of migration potentials, and formed bone-like nodules in vitro. They expressed alpha5, beta1, alpha v, and alpha4 integrin subunits, known receptors for FN, and in fact they bound FN preferentially at 5 and 10 microg/ml. Intact FN induced greater PDL cell proliferation and chemotaxis than did FN fragments (120-kDa cell-binding, 60-kDa heparin-binding, and 45-kDa collagen-binding). PDL cells harvested from diseased and healthy conditions were no different on the basis of these assays. These data demonstrate that PDL cells are a mixed population of fibroblastic cells, capable of forming a mineralized matrix. They also suggest that maximal proliferation and chemotaxis require specific FN domains that are present on the intact molecule but not its fragments.
纤连蛋白（Fn）是一种细胞外基质（ECM）分子，在细胞黏附、迁移以及伤口愈合过程中发挥着重要作用。它在牙周韧带（PDL）细胞与ECM的相互作用中可能也起着重要作用，进而在牙周组织再生方面发挥作用。在本研究中，我们对PDL细胞及其与Fn的相互作用进行了表征，测试了取自健康和患病状态的不同PDL细胞分离株。通过细胞形态、整合素谱、运动性和骨结节形成对PDL细胞进行表征。然后检测细胞对Fn或Fn片段的黏附、增殖和趋化反应。细胞分离株在形态上具有异质性且呈成纤维细胞样，具有外观正常的肌动蛋白细胞骨架和广泛的迁移潜能，并在体外形成骨样结节。它们表达α5、β1、αv和α4整合素亚基，这些都是已知的Fn受体，事实上它们在5和10μg/ml时优先结合Fn。完整的Fn比Fn片段（120 kDa细胞结合片段、60 kDa肝素结合片段和45 kDa胶原结合片段）诱导更强的PDL细胞增殖和趋化作用。基于这些检测，取自患病和健康状态的PDL细胞并无差异。这些数据表明，PDL细胞是成纤维细胞的混合群体，能够形成矿化基质。它们还表明，最大程度的增殖和趋化作用需要完整分子上存在但片段中不存在的特定Fn结构域。
