Kanagaraja S, Lundström I, Nygren H, Tengvall P
Department of Anatomy and Cell Biology, Göteborg University, Sweden.
Biomaterials. 1996 Dec;17(23):2225-32. doi: 10.1016/0142-9612(95)00311-8.
Protein adsorption from human plasma and platelet binding and activation were studied at short blood-titanium/gold contact times. The protein adsorption was studied by ellipsometry-antibody techniques in situ, and adhering platelets were visualized with fluorescein isothiocyanate-labelled anti-CD 61 antibodies. Adhering platelets were quantified by counting labelled cells in microscopic image fields. The spreading of platelets was studied by scanning electron microscopy. The results show that after 1 min of plasma exposure, fibrinogen, IgG and albumin were detectable with antibodies on both surfaces. The amount of deposited fibrinogen and complement decreased with time on titanium, and the amount of adsorbed anti-high molecular weight kininogen increased. No complement was detected on gold surfaces after plasma incubation, and the antibody binding pattern also remained unchanged after prolonged plasma exposure. The surface-bound platelets were found to spread on the gold but not on titanium surfaces. C1q has been shown to induce the expression of P-selectin, i.e. cause secretion reactions in platelets. In this study secreted platelet-microvesicles were found on gold, but not on the titanium surfaces that bound significant amounts of C1q. Thus, the results of the present study indicate that the mixture of fibrinogen, C1q and kininogens, whilst causing adhesion and aggregation, does not result in the activation and microvesicle secretion of platelets. Platelet activation on biomaterial surfaces thus seems to be governed by the mixture of proteins present on that surface, and no one particular protein need cause a known reaction in platelets as obtained when platelets are exposed only to that particular protein.
在短时间血液与钛/金接触的情况下，研究了人血浆中的蛋白质吸附以及血小板的黏附与活化。通过椭圆偏振光抗体技术原位研究蛋白质吸附情况，并用异硫氰酸荧光素标记的抗CD 61抗体使黏附的血小板可视化。通过对显微镜图像视野中的标记细胞进行计数来定量黏附的血小板。通过扫描电子显微镜研究血小板的铺展情况。结果表明，血浆暴露1分钟后，在两种表面上均能用抗体检测到纤维蛋白原、IgG和白蛋白。钛表面上沉积的纤维蛋白原和补体的量随时间减少，而吸附的抗高分子量激肽原的量增加。血浆孵育后在金表面未检测到补体，长时间血浆暴露后抗体结合模式也保持不变。发现表面结合的血小板在金表面上铺展，但在钛表面上不铺展。已证明C1q可诱导P-选择素的表达，即引起血小板中的分泌反应。在本研究中，在金表面上发现了分泌的血小板微泡，但在结合大量C1q的钛表面上未发现。因此，本研究结果表明，纤维蛋白原、C1q和激肽原的混合物虽然会引起黏附和聚集，但不会导致血小板的活化和微泡分泌。因此，生物材料表面上的血小板活化似乎受该表面上存在的蛋白质混合物的控制，而且当血小板仅暴露于某一种特定蛋白质时，并不一定是某一种特定蛋白质会在血小板中引发已知反应。
