Ingram Joanne Helen, Stone Martin, Fisher John, Ingham Eileen
Department of Microbiology, School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
Biomaterials. 2004 Aug;25(17):3511-22. doi: 10.1016/j.biomaterials.2003.10.054.
The response of murine macrophages to clinically relevant polyethylene wear particles generated from different polyethylenes at various time points and volumetric doses in vitro was evaluated. Clinically relevant ultra high molecular weight polyethylene (UHMWPE) wear debris was generated in vitro in a lubricant of RPMI 1640 supplemented with 25% (v/v) foetal calf serum using a multi-directional pin-on-plate wear rig under sterile conditions. Wear debris was cultured with C3H murine peritoneal macrophages at various particle volume (microm(3)): cell number ratios. The secretion of TNF-alpha was determined by ELISA. Initially the effect of molecular weight of UHMWPE was considered. Higher molecular weight GUR415HP was shown to have a lower wear rate than the lower molecular weight GUR1120, however a greater volume of the wear debris produced by the high molecular weight GUR415HP was in the 0.1-1.0 microm size range. Wear debris from GUR415HP produced significant levels of TNF-alpha at a concentration of 1 microm(3)/cell while at least 10 microm(3)/cell of GUR1120 wear debris per cell was needed to produce significant levels of TNF-alpha. Secondly the effects of crosslinking GUR1050 was examined when worn against a scratched counterface. The wear rate of the material was shown to decrease as the level of crosslinking increased. However the materials crosslinked with 5 and 10 Mrad of gamma irradiation produced higher percentages of 0.1-1.0 microm size wear particles than the non-crosslinked material. While the crosslinked material was able to stimulate cells to produce significantly elevated TNF-alpha levels at a particle concentration of just 0.1 microm(3)/cell only concentrations of 10 microm(3)/cell and above of the non-crosslinked wear debris were stimulatory. When the counterface was changed from scratched to smooth the wear rate for all three GUR1050 materials was further reduced. For the first time nanometre size wear particles were observed from polyethylene which reduced the percentage mass of debris in the 0.1-1.0 microm size range. For all three materials on the smooth counterface only concentrations of 50 microm(3)/cell and above were stimulatory. This study has demonstrated that molecular weight, crosslinking and counterface roughness are important factors in determining the biological activity of polyethylene.
评估了小鼠巨噬细胞对不同聚乙烯在体外不同时间点和体积剂量下产生的临床相关聚乙烯磨损颗粒的反应。在无菌条件下，使用多向销盘磨损试验台，在补充有25%（v/v）胎牛血清的RPMI 1640润滑剂中体外产生临床相关的超高分子量聚乙烯（UHMWPE）磨损碎片。将磨损碎片与C3H小鼠腹腔巨噬细胞以不同的颗粒体积（立方微米）：细胞数量比进行培养。通过酶联免疫吸附测定法（ELISA）测定肿瘤坏死因子-α（TNF-α）的分泌。最初考虑了UHMWPE分子量的影响。结果表明，较高分子量的GUR415HP的磨损率低于较低分子量的GUR1120，然而，高分子量的GUR415HP产生的磨损碎片中，更大体积的碎片在0.1 - 1.0微米尺寸范围内。来自GUR415HP的磨损碎片在浓度为1立方微米/细胞时产生显著水平的TNF-α，而来自GUR1120的磨损碎片每细胞至少需要10立方微米/细胞才能产生显著水平的TNF-α。其次，研究了GUR1050与划痕对磨面磨损时交联的影响。结果表明，随着交联程度的增加，材料的磨损率降低。然而，用5和10兆拉德γ射线辐照交联的材料产生的0.1 - 1.0微米尺寸磨损颗粒的百分比高于未交联材料。虽然交联材料在颗粒浓度仅为0.1立方微米/细胞时就能刺激细胞产生显著升高的TNF-α水平，但未交联磨损碎片仅在浓度为10立方微米/细胞及以上时才具有刺激作用。当对磨面从划痕变为光滑时，所有三种GUR1050材料的磨损率进一步降低。首次从聚乙烯中观察到纳米尺寸的磨损颗粒，这降低了0.1 - 1.0微米尺寸范围内碎片的质量百分比。对于光滑对磨面上的所有三种材料，仅在浓度为50立方微米/细胞及以上时才具有刺激作用。这项研究表明，分子量、交联和对磨面粗糙度是决定聚乙烯生物活性的重要因素。
