Fujii Takashi, Ueno Takaaki, Kagawa Toshimasa, Sugahara Toshio, Yamamoto Toshio
Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Dental School, 2-5-1 Shikata-cho, Okayama 700-8525, Japan.
Acta Histochem. 2005;106(6):427-37. doi: 10.1016/j.acthis.2004.10.002. Epub 2005 Jan 13.
Sox9 is a transcription factor belonging to the SRY family of high-mobility box proteins, and plays a major role in endochondral ossification. Sox9 is a potent activator of the type-2 collagen pheno-type marker of articular cartilage. Regulation of osteogenic molecular signals in periosteal bone formation has not yet been elucidated yet. The purpose of the present study was to analyze histologically the bone formation in surgically released and repositioned periosteum, and to determine expression of Sox9 and type-2 collagen in periosteal bone formation of tibia and calvaria. After surgery, the released tibial periosteum formed ectopic cartilage. At 7 days, a combination of endochondral and intramembranous ossification was apparent. Some fibroblasts derived from the released periosteum showed Sox9 expression. Chondrocytes and cartilage matrix both displayed type-2 collagen expression. At 7 days, an additional new bone was formed on the calvaria. Osteoblasts and fibroblasts derived from released calvarial periosteum did not express Sox9 or type-2 collagen. Sox9 was not expressed throughout the process periosteal bone formation on the calvaria. It is concluded that we revealed Sox9 and type-2 collagen expression in periosteal cells after periosteum release and that the generative potential of periosteal cells of calvaria is different from that of tibia.
Sox9是一种属于高迁移率族蛋白SRY家族的转录因子，在软骨内成骨过程中发挥主要作用。Sox9是关节软骨2型胶原蛋白表型标志物的有效激活剂。骨膜骨形成过程中骨生成分子信号的调控尚未阐明。本研究的目的是从组织学角度分析手术松解并重新定位后的骨膜中的骨形成情况，并确定Sox9和2型胶原蛋白在胫骨和颅骨骨膜骨形成中的表达。手术后，松解的胫骨骨膜形成异位软骨。在第7天，软骨内成骨和膜内成骨同时出现。一些源自松解骨膜的成纤维细胞显示出Sox9表达。软骨细胞和软骨基质均显示2型胶原蛋白表达。在第7天，颅骨上形成了额外的新骨。源自松解颅骨骨膜的成骨细胞和成纤维细胞未表达Sox9或2型胶原蛋白。在颅骨骨膜骨形成的整个过程中均未检测到Sox9表达。研究得出结论，我们揭示了骨膜松解后骨膜细胞中Sox9和2型胶原蛋白的表达情况，并且颅骨骨膜细胞的生成潜能与胫骨不同。
