Germain M A, Hatton A, Williams S, Matthews J B, Stone M H, Fisher J, Ingham E
Division of Microbiology, School of Biochemistry and Molecular Biology, University of Leeds, LS2 9T Leeds, UK.
Biomaterials. 2003 Feb;24(3):469-79. doi: 10.1016/s0142-9612(02)00360-5.
Concern over polyethylene wear particle induced aseptic loosening of metal-on-polyethylene hip prostheses has led to renewed interest in alternative materials such as metal-on-metal and alumina ceramic-on-alumina ceramic for total hip replacement. This study compared the effects of clinically relevant cobalt-chromium and alumina ceramic wear particles on the viability of U937 histiocytes and L929 fibroblasts in vitro. Clinically relevant cobalt-chromium wear particles were generated using a flat pin-on-plate tribometer. The mean size of the clinically relevant metal particles was 29.5+/-6.3 nm (range 5-200 nm). Clinically relevant alumina ceramic particles were generated in the Leeds MkII anatomical hip simulator from a Mittelmieier prosthesis using micro-separation motion. This produced particles with a bimodal size distribution. The majority (98%) of the clinically relevant alumina ceramic wear debris was 5-20 nm in size. The cytotoxicity of the clinically relevant wear particles was compared to commercially available cobalt-chromium (9.87 microm+/-5.67) and alumina ceramic (0.503+/-0.19 microm) particles. The effects of the particles on the cells over a 5 day period at different particle volume (microm(3)) to cell number ratios were tested and viability determined using ATP-Lite(TM). Clinically relevant cobalt-chromium particles 50 and 5 microm(3) per cell reduced the viability of U937 cells by 97% and 42% and reduced the viability of L929 cells by 95% and 73%, respectively. At 50 microm(3) per cell, the clinically relevant ceramic particles reduced U937 cell viability by 18%. None of the other concentrations of the clinically relevant particles were toxic. The commercial cobalt-chromium and alumina particles did not affect the viability of either the U937 histiocytes or the L929 fibroblasts.Thus at equivalent particle volumes the clinically relevant cobalt-chromium particles were more toxic then the alumina ceramic particles. This study has emphasised the fact that the nature, size and volume of particles are important in assessing biological effects of wear debris on cells in vitro.
对聚乙烯磨损颗粒导致金属对聚乙烯髋关节假体无菌性松动的担忧，引发了人们对金属对金属和氧化铝陶瓷对氧化铝陶瓷等替代材料用于全髋关节置换的新兴趣。本研究比较了临床相关的钴铬和氧化铝陶瓷磨损颗粒对U937组织细胞和L929成纤维细胞体外活力的影响。使用平板销盘摩擦磨损试验机生成临床相关的钴铬磨损颗粒。临床相关金属颗粒的平均尺寸为29.5±6.3纳米（范围为5 - 200纳米）。临床相关的氧化铝陶瓷颗粒是在利兹MkII解剖型髋关节模拟器中，使用米特尔迈尔假体通过微分离运动生成的。这产生了具有双峰尺寸分布的颗粒。临床相关氧化铝陶瓷磨损碎片的大部分（98%）尺寸为5 - 20纳米。将临床相关磨损颗粒的细胞毒性与市售的钴铬（9.87微米±5.67）和氧化铝陶瓷（0.503±0.19微米）颗粒进行比较。在不同的颗粒体积（立方微米）与细胞数量比下，测试颗粒在5天内对细胞的影响，并使用ATP-Lite™测定活力。每细胞50和5立方微米的临床相关钴铬颗粒分别使U937细胞的活力降低97%和42%，使L929细胞的活力降低95%和73%。每细胞50立方微米时，临床相关陶瓷颗粒使U937细胞活力降低18%。其他临床相关颗粒浓度均无毒性。市售的钴铬和氧化铝颗粒均未影响U937组织细胞或L929成纤维细胞的活力。因此，在等效颗粒体积下，临床相关的钴铬颗粒比氧化铝陶瓷颗粒毒性更大。本研究强调了颗粒的性质、大小和体积在评估磨损碎片对体外细胞生物学效应方面很重要这一事实。
