Sun An-Ke, Pei Guo-Xian, Zhou Guo-Ping, Chen Wen-Xuan
Department of Orthopedics and Traumatology, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China.
Di Yi Jun Yi Da Xue Xue Bao. 2002 Nov;22(11):996-9.
To improve the method for constructing allogeneic molded cartilage by means of tissue engineering techniques.
The chondrocytes from the rib and articular cartilage of infant rabbits were harvested by type II collagenase digestion, followed by in vitro cell culture for 3 to 4 passages. The chondrocytes were then prepared into cell suspension and seeded onto C -and O -shaped pre-molded polyglycolic acid (PGA) scaffolds form chondrocyte-PGA composites, which were subsequently cultured in vitro for 7 to 10 d before implanted subcutaneously into adult rabbits. Improvement was made upon conventional shaping and implantation procedures. Morphological observation and cartilage regeneration assessment were conducted at different time points following the implantation, in comparison with the observation by conventional shaping and implantation methods.
During in vitro cell culture, the rate of viable chondrocytes in the final cell suspension was (92+/-2)% after well-controlled prolongation of digestion trypsin, similar to the viable cell rate (93+/-2) % by traditional procedures (P>0.05). Gross observation found milk-white, newly generated cartilage which had good flexibility 4 weeks after implantation, and after 8 weeks and later, the cartilage took on the color of porcelain-white. Histological examination showed a few inflammatory cells around the newly generated immature cartilage 4 weeks after implantation, and the inflammation abated when the newly generated cartilage acquired similar histological properties to that of the original cartilage 8 weeks postoperatively and later. After 16 weeks, no blood vessel or capillaries were visible within the new cartilage.
The chondrocyte viability is not affected when the cells are treated with well-controlled prolonged digestion with trypsin during in vitro cell culture. Improved PGA scaffolds shaping and the implantation procedure facilitate the regeneration of the cartilage after the implantation of the composites.
通过组织工程技术改进同种异体成型软骨构建方法。
采用Ⅱ型胶原酶消化法从幼兔肋骨和关节软骨中获取软骨细胞，体外细胞培养3至4代。然后将软骨细胞制成细胞悬液，接种到C形和O形预成型聚乙醇酸（PGA）支架上形成软骨细胞 - PGA复合材料，随后体外培养7至10天，再皮下植入成年兔体内。对传统成型和植入程序进行了改进。在植入后的不同时间点进行形态学观察和软骨再生评估，并与传统成型和植入方法的观察结果进行比较。
体外细胞培养过程中，通过控制胰蛋白酶消化时间，最终细胞悬液中活软骨细胞率为（92±2）%，与传统方法的活细胞率（93±2）%相似（P>0.05）。大体观察发现，植入后4周有乳白色、柔韧性良好的新生软骨，8周及以后软骨呈瓷白色。组织学检查显示，植入后4周新生未成熟软骨周围有少量炎性细胞，术后8周及以后新生软骨的组织学特性与原软骨相似时炎症减轻。16周后，新软骨内未见血管或毛细血管。
体外细胞培养时，用胰蛋白酶控制消化时间延长处理细胞不影响软骨细胞活力。改进的PGA支架成型和植入程序有利于复合材料植入后软骨的再生。
