Duan Wangping, Zhao Yu, Ren Xiaochun, Zhao Ruipeng, Li Qi, Sun Zhenwei, Song Wenjie, Yang Yanfei, Li Pengcui, Wei Xiaochun
Department of Orthopaedics, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, China.
Shanxi Key Laboratory of Bone and Soft Tissue Injury Repair, Taiyuan, Shanxi, 030001, China.
J Orthop Translat. 2021 Feb 23;28:47-54. doi: 10.1016/j.jot.2021.01.004. eCollection 2021 May.
Chondrons are composed of chondrocytes and the surrounding pericellular matrix (PCM) and function to enhance chondrocyte-mediated cartilage tissue engineering. This study aimed at investigating the potential effect of combined chondrocytes with chondrons on the production of proteoglycan and collagen-II (Col-2) and the repair of defective knee cartilage in rabbits.
Chondrocytes and chondrons were isolated from the knee cartilage of rabbits, and cultured alone or co-cultured for varying periods in vitro. Their morphology was characterized by histology. The levels of aggrecan (AGG), Col-2 and glycosaminoglycan (GAG) expression were quantified by qRT-PCR, Alcian blue-based precipitation and ELISA. The effect of combined chondrocytes with chondrons in alginate spheres on the repair of defective knee cartilage was examined in rabbits.
The isolated chondrocytes and chondrons displayed unique morphology and began to proliferate on day 3 and 6 post culture, respectively, accompanied by completely degenerated PCM on day 6 post culture. Evidently, chondrocytes had stronger proliferation capacity than chondrons. Longitudinal analyses indicated that culture of chondrons, but not chondrocytes, increased AGG mRNA transcripts and GAG levels with time and Col-2 mRNA transcripts only on day 3 post culture. Compared with chondrocytes or chondrons alone, co-culture of chondrocytes and chondrons significantly up-regulated AGG and Col-2 expression and GAG production, particularly at a ratio of 1:1. Implantation with chondrocytes and chondrons at 1:1 significantly promoted the repair of defective knee cartilage in rabbits, accompanied by reduced the Wakiteni scores with time.
Combined chondrons with chondrocytes promoted the production of extracellular matrix and the repair of defective knee cartilage in rabbits.
This study explores that the combination of chondrons and chondrocytes may be new therapeutic strategy for cartilage tissue engineering and repair of defective cartilage.
软骨粒由软骨细胞和周围的细胞周基质（PCM）组成，其功能是增强软骨细胞介导的软骨组织工程。本研究旨在探讨软骨细胞与软骨粒联合应用对蛋白聚糖和Ⅱ型胶原蛋白（Col-2）产生以及兔膝关节软骨缺损修复的潜在影响。
从兔膝关节软骨中分离软骨细胞和软骨粒，分别单独培养或体外共培养不同时间。通过组织学对其形态进行表征。采用qRT-PCR、阿尔新蓝沉淀法和ELISA对聚集蛋白聚糖（AGG）、Col-2和糖胺聚糖（GAG）的表达水平进行定量分析。在兔体内研究了藻酸盐球中软骨细胞与软骨粒联合应用对膝关节软骨缺损修复的作用。
分离出的软骨细胞和软骨粒呈现独特形态，分别在培养后第3天和第6天开始增殖，培养后第6天PCM完全退化。显然，软骨细胞的增殖能力强于软骨粒。纵向分析表明，软骨粒培养而非软骨细胞培养，随着时间的推移会增加AGG mRNA转录本和GAG水平，且Col-2 mRNA转录本仅在培养后第3天增加。与单独的软骨细胞或软骨粒相比，软骨细胞与软骨粒共培养显著上调了AGG和Col-2的表达以及GAG的产生，尤其是在1:1的比例下。以1:1比例植入软骨细胞和软骨粒显著促进了兔膝关节软骨缺损的修复，并随着时间的推移降低了Wakiteni评分。
软骨粒与软骨细胞联合应用促进了兔细胞外基质的产生和膝关节软骨缺损的修复。
本研究探索了软骨粒与软骨细胞的联合应用可能是软骨组织工程和软骨缺损修复的新治疗策略。
