Migratory chondrogenic progenitor cells from repair tissue during the later stages of human osteoarthritis. Homo sapiens

The regeneration of diseased hyaline cartilage remains a great challenge, mainly because degeneration activities after major injury or due to age-related processes overwhelm the self-renewal capacity of the tissue. We show that repair tissue from human articular cartilage of late stages of osteoarthritis harbor a unique progenitor cell population, termed chondrogenic progenitor cells exhibiting stem cell characteristics, such as multipotency, lack of immune system activation and, in particular, migratory activity. The isolated CPC exhibit a high chondrogenic potential and were able to populate diseased tissue in vivo. Moreover, down-regulation of the osteogenic transcription factor runx-2 enhanced the expression of the chondrogenic transcription factor sox-9 and consequently the matrix synthesis potential of chondrogenic progenitor cells. Our results, while offering new insight into the biology of progenitor cells from diseased cartilage tissue, might assist future strategies to treat late stages of osteoarthritis. Keywords: cell type comparison Overall design: Characterization chondrogenic progenitor cells in P1 of 3 male and 3 female patients with late-stage OA in comparison to healthy chondrocytes in P1

病变透明软骨的再生仍是一项重大临床挑战，究其核心原因，重度损伤后或年龄相关性退变进程所介导的组织退变程度，远超该组织自身的自我更新能力。本研究证实，晚期骨关节炎（osteoarthritis，OA）患者的人关节软骨修复组织中，存在一类独特的祖细胞群——我们将其命名为软骨形成祖细胞（chondrogenic progenitor cells，CPC），该类细胞具备典型干细胞特性：包括多向分化潜能、无免疫激活反应，尤其展现出优异的迁移活性。分离获得的软骨形成祖细胞具有较高的软骨形成潜能，且可在体内定植于病变软骨组织。此外，下调成骨转录因子runx-2可上调软骨形成转录因子sox-9的表达，进而显著增强软骨形成祖细胞的基质合成能力。本研究结果不仅为病变软骨组织来源的祖细胞生物学特性提供了全新认知，还有望为未来晚期骨关节炎的治疗策略开发提供重要理论参考。关键词：细胞类型比较 整体实验设计：对比分析3名男性与3名女性晚期骨关节炎患者原代第1代（P1）软骨形成祖细胞，与健康软骨细胞原代第1代（P1）的特征。