Gutensohn K, Beythien C, Bau J, Fenner T, Grewe P, Koester R, Padmanaban K, Kuehnl P
Departments of Transfusion Medicine and Transplantation Immunology, Hamburg, Germany.
Thromb Res. 2000 Sep 15;99(6):577-85. doi: 10.1016/s0049-3848(00)00295-4.
Coronary artery stents can induce platelet activation by shear forces, contact to the biomaterial, and release of metal ions. This activation is one important trigger for thrombosis. Coating of stents is a possible approach to prevent this side effect. The purpose of this study was to evaluate in vitro the biocompatibility of stents coated with diamond-like carbon (DLC). Semiquantitative energy-dispersive X-ray microanalyses showed a complete coverage of the DLC stents. Flow cytometric analyses revealed a significantly higher increase of mean channel fluorescence intensity for the activation-dependent antigens CD62p and CD63 in non-coated compared to DLC-coated stents (p<0.05). Atomic adsorption spectrophotometry analyses revealed a significant release of nickel and chromium metal ions by non-coated stents over a storage period of 96 hours in human plasma (p<0.05). In contrast, only minimal concentrations of released ions could be detected in the case of DLC-coated stents. Similar observations were made with inductively coupled plasma mass spectrometry analyses. Here, high concentrations of molybdenum and manganese ions were released from non-coated stents (p<0.05), while release of these ions from DLC-coated stents was virtually undetectable (p=0.1 for molybdenum and p=0.4 for manganese). Coating of intracoronary stents with diamond-like carbon significantly improves biocompatibility. This biocompatible coating may therefore contribute to a reduction in thrombogenicity.
冠状动脉支架可通过剪切力、与生物材料的接触以及金属离子的释放诱导血小板活化。这种活化是血栓形成的一个重要触发因素。支架涂层是预防这种副作用的一种可能方法。本研究的目的是在体外评估类金刚石碳（DLC）涂层支架的生物相容性。半定量能量色散X射线微分析显示DLC支架完全被覆盖。流式细胞术分析显示，与DLC涂层支架相比，未涂层支架中活化依赖性抗原CD62p和CD63的平均通道荧光强度显著升高（p<0.05）。原子吸收分光光度法分析显示，未涂层支架在人血浆中储存96小时后，镍和铬金属离子有显著释放（p<0.05）。相比之下，DLC涂层支架仅能检测到极低浓度的释放离子。电感耦合等离子体质谱分析也有类似的观察结果。在此，未涂层支架释放出高浓度的钼和锰离子（p<0.05），而DLC涂层支架几乎检测不到这些离子的释放（钼的p=0.1，锰的p=0.4）。用类金刚石碳涂层冠状动脉支架可显著提高生物相容性。因此，这种生物相容性涂层可能有助于降低血栓形成倾向。
