山羊颞下颌关节盘细胞类型及分布表征在组织构建中的设计意义：

Type and distribution of cells in goat temporomandibular joint discs and its significance in tissue engineering design

背景:颞下颌关节盘的细胞分型分布尚无定论,对细胞的描述使用的名称也不统一。目的:表征山羊颞下颌关节盘中细胞的分型及分布。设计、时间及地点:单一样本观察,于2007-03/05在兰州大学细胞与分子生物学实验中心、电镜中心完成。材料:颞下颌关节盘取自两只新鲜屠宰的1月龄健康山羊。方法:完整切取山羊双侧颞下颌关节盘,按长轴(内外侧向)及短轴(前后向)分别等分为3部分和两部分,将关节盘分为6份。标记后用体积分数为10%中性甲醛固定24h,石蜡包埋。主要观察指标:苏木精-伊红染色观察关节盘各带细胞类型及数目的不同,甲苯胺蓝染色,Ⅰ型胶原免疫组织化学检测胶原的分布,透射电镜观察细胞超微结构。结果:颞下颌关节盘由不均分布的细胞和胶原纤维组成。胶原几乎都为Ⅰ型,胶原纤维一般表现为波浪形或卷曲状,纤维大致平行,而细胞散在胶原纤维基质中。细胞有成纤维细胞样细胞和软骨细胞样细胞两种,其中前者占优势,两者比例约为2.05∶1。细胞类型和分布在各区没有显著性差异。电镜超微结构显示成纤维细胞样细胞核大,梭形或不规则形,细胞器很少。软骨细胞样细胞胞核圆形或椭圆形,周围有电子透射区,细胞囊不明显,伪足少见。结论:1月龄山羊颞下颌关节盘内各个区域的细胞类型、数目与排列差异没有显著性意义。其中成纤维细胞样细胞较软骨细胞样略占优势。

BACKGROUND： There is no common cognition in the cell type in the temporomandibular joint （TMJ） discs, and names describing TMJ disc cells also vary a lot. OBJECTIVE： To characterize the type and the distribution of cells in the TMJ disc of goats DESIGN, TIME AND SETTING： A single sample observation was completed in Cellular and Molecular Biological Center and Electron Microscope Center of Lanzhou University from March to May in 2007. MATERIALS： TMJ discs were obtained from two one-month-old healthy goats that were slaughtered freshly. METHODS： Bilateral TMJ discs of goats were cut off completely and were divided into 6 parts by 3 cuts in the major axis direction （mediolaterally） and 2 cuts in the minor axis direction （anteroposteriorly）. Then the marked samples were fixed in 10% neutral formalin liquid for 24 hours and embedded by paraffin. MAIN OUTCOME MEASURES： Hematoxylin and eosin staining were used to identify regional variation of cell type and cell numbers. Toluidine blue staining and collagen type I immunohistochemical assay were performed to test the distribution of collagens. Transmission electron microscopy was used to observe the ultrastructure of cells of goat TMJ discs. RESULTS： TMJ discs were comprised of cells and collagen fibers distributing unevenly. Collagens were mostly type I. Collagen fibers were wave or crimping and approximately parallel to each other, with cells scattered in their matrix. Fibroblast-like cells and chondrocyte-like cells were the main two types of cells existing, with the former predominating over the later in a ratio of 2.05：1 approximately. There were no significant regional differences in cell type and distribution statistically. Transmission electron microscopy denoted that fibroblast-like cells have fairly larger fusiform or irregular nuclei with very few organelles, while the chondrocyte-like cells exhibited round or elliptical nuclei, well defined pericellular electron lucent zones, unconspicuous cytocysts and non-distinctive pseudopodia. CONCLUSION： There are no significant differences in type, number and arrangement of cells in TMJ discs of one-month-old goats statistically, with Fibroblast-like cells predominating slightly over chondrocyte-like cells.