软骨组织工程研究中细胞源-软骨细胞和成纤维细胞

目前关节软骨仍是供软骨修复的主要软骨细胞来源，但获得关节面软骨本身是一种有创操作，且细胞的低产量，低有丝分裂率，低生物活性进一步限制了关节软骨作为供体细胞来源的实际临床应用。体内其他作为自体软骨细胞源包括耳骨、鼻中隔、肋软骨、颞颌关节髁突软骨等，而不同的软骨源具有不同的结构、组成和功能，产生具有不同生化、物理和生物力学特性的细胞及细胞外基质。目前用于软骨再生的软骨细胞主要来源于幼稚动物，这些刚出生的和幼体动物的软骨细胞较年老供体的软骨细胞增殖率高，形成软骨的潜能较强。皮肤可为组织工程提供一种侵袭性小、来源丰富的成纤维细胞源。将成纤维细胞直接置于软骨缺损的聚乳酸网格会导致纤维组织增生，然而在恰当的培养条件下，成纤维细胞可以被诱导向软骨细胞表型转化。

Cell resources in cartilage tissue engineering research: Chondrocyte and fibroblast

Articular chondrocytes are the main cell sources for cartilage repair. However, the harvesting of articular cartilage is a highly invasive procedure accompanied by the potential site morbidity and loss of function for donor. In addition, low cell yields, low mitotic rates, and low bioactivity further limit the use of articular chondrocytes in clinic. Other potential autologous chondrocyte sources in vivo include auricular, nasoseptal and costal cartilage with differences function, structure, and composition which result in different discrete biochemical, physical and biomechanical properties. Presently, efforts in cartilage regeneration mainly focus on chondrocytes isolated from immature animals, which have faster growth rate and rapid capacity for differentiation than those from old donors. Skin presents a minimally invasive, relatively abundant source of fibroblasts for tissue engineering. Although the direct transplantation of fibroblasts on PLA meshes in a cartilage defect may leads to fibroplasia, fibroblasts can be induced differentiated into chondrogenic phenotype under the appropriate culture conditions.