Khan Wasim S, Johnson David S, Hardingham Timothy E
UK Centre for Tissue Engineering, University of Manchester, Oxford Road, M13 9PL UK.
Knee. 2010 Dec;17(6):369-74. doi: 10.1016/j.knee.2009.12.003. Epub 2010 Jan 3.
Cartilage is frequently damaged but only shows a limited capacity for repair. There are a number of treatment strategies currently available for the repair of articular cartilage defects including abrasion chondroplasty, subchondral drilling, microfracture and mosaicplasty but these show variable results. For the younger patients, there is great interest in the potential of cell-based strategies to provide a biological replacement of damaged cartilage using autologous chondrocytes. The results of clinical studies using these cell-based techniques do not conclusively show improvement over conventional techniques. These techniques also do not consistently result in the formation of the desired hyaline cartilage rather than fibrocartilage. Mesenchymal stem cells present a promising cell source for cartilage repair. Mesenchymal stem cells have been isolated from a number of adult tissues including the bone marrow and the synovial fat pad. These cells have the ability to proliferate in culture and differentiate down different pathways including the chondrogenic pathway. In the first instance, differentiated stem cells can be used for the repair of localised cartilage defects by producing hyaline cartilage. In the future, this strategy has the potential to be extended to treat more generalised cartilage defects, especially as the cell source is not a limiting factor. The use of cell-based therapies also allows the versatility of using scaffolds and growth factors, with recombinant proteins or gene therapy. A number of challenges however still need to be overcome including further work on identifying the optimal source of stem cells, along with refining the conditions that enhance expansion and chondrogenesis.
软骨经常受损，但修复能力有限。目前有多种治疗策略可用于修复关节软骨缺损，包括软骨磨削术、软骨下钻孔、微骨折术和镶嵌植骨术，但这些方法的效果各不相同。对于年轻患者，人们对基于细胞的策略潜力非常感兴趣，即使用自体软骨细胞为受损软骨提供生物替代物。使用这些基于细胞技术的临床研究结果并未确凿表明其比传统技术有改善。这些技术也并非始终能形成所需的透明软骨而非纤维软骨。间充质干细胞是软骨修复有前景的细胞来源。间充质干细胞已从包括骨髓和滑膜脂肪垫在内的多种成人组织中分离出来。这些细胞能够在培养中增殖，并沿着不同途径分化，包括软骨生成途径。首先，分化的干细胞可通过产生透明软骨用于修复局部软骨缺损。未来，这种策略有可能扩展到治疗更广泛的软骨缺损，特别是因为细胞来源不是限制因素。基于细胞的疗法还允许使用支架和生长因子，以及重组蛋白或基因疗法的多功能性。然而，仍有许多挑战需要克服，包括进一步确定干细胞的最佳来源，以及优化促进扩增和成软骨的条件。
