Arciola Carla Renata, Bustanji Yasser, Conti Matteo, Campoccia Davide, Baldassarri Lucilla, Samorì Bruno, Montanaro Lucio
Research Laboratory for Biocompatibility on Implant Materials, Rizzoli Orthopaedic Institute, Via di Barbiano, 1/10, 40136 Bologna, Italy
Biomaterials. 2003 Aug;24(18):3013-9. doi: 10.1016/s0142-9612(03)00133-9.
Staphylococcus epidermidis is able to adhere onto biomaterials and to cause implant infections. Recently, host matrix proteins, which in vivo cover the implants, have been indicated as substrates for adhesion by specific bacterial adhesins. Here, the binding of S. epidermidis to fibronectin, a main protein of the extracellular matrix, and the effect of heparin on this interaction were studied by dynamic force spectroscopy (DFS). Novelties are that S. epidermidis strains analysed by DFS were clinical isolates from prosthesis-associated infections, genotyped and phenotyped for their adhesion properties to fibronectin and examined as living cells. Thus, fibronectin-binding staphylococci adhered to the fibronectin-coated substratum and formed a continuous layer assuring their contact with the fibronectin-coated cantilever tip during the approach-retraction cycles of the DFS measurements. Results show that only a single molecular binding site of fibronectin is involved in the interaction with S. epidermidis, that it takes place at the domain near the C-terminus and that it is specifically inhibited by heparin.
表皮葡萄球菌能够黏附于生物材料并引发植入物感染。近来，体内覆盖植入物的宿主基质蛋白已被指出是特定细菌黏附素的黏附底物。在此，通过动态力谱（DFS）研究了表皮葡萄球菌与细胞外基质的主要蛋白纤连蛋白的结合以及肝素对这种相互作用的影响。新颖之处在于，通过DFS分析的表皮葡萄球菌菌株是来自假体相关感染的临床分离株，对其与纤连蛋白的黏附特性进行了基因分型和表型分析，并作为活细胞进行检测。因此，结合纤连蛋白的葡萄球菌黏附于纤连蛋白包被的基质上，并形成连续层，确保在DFS测量的接近-回缩循环中它们与纤连蛋白包被的悬臂尖端接触。结果表明，纤连蛋白仅一个分子结合位点参与与表皮葡萄球菌的相互作用，该相互作用发生在靠近C端的结构域，并且它被肝素特异性抑制。
