臨床整形外科43巻12号

2008年12月発行

最新基礎科学／知っておきたい

Sox9研究の進歩

著者： 秋山治彦¹

所属機関： ¹京都大学医学部整形外科学

ページ範囲：P.1220 - P.1223

■軟骨細胞の発生と分化

　われわれの身体の多くの骨は，軟骨を鋳型とする内軟骨性骨化によって形成される．よって軟骨の異常は生後の骨格異常を来し，また，思春期までは成長軟骨板の異常による成長障害，成人では関節軟骨の変性による変形性関節症などの病気を引き起こす．成人の生体内での正常軟骨（ここでは硝子様軟骨を指すこととする）の形成は，骨折の治癒過程に認められる程度であり，関節軟骨などの修復機転は発生過程を正確に再現するものではない．胎生期の軟骨細胞は神経堤細胞や間葉系細胞の多分化能を有する細胞に由来する．これらの細胞はある時期に凝集し，軟骨細胞へと細胞形態を変化させる．発生した軟骨細胞は軟骨特異的な基質蛋白質を分泌しながら増殖，成熟し，最終的には基質の石灰化を経て骨へと置換される．軟骨細胞の発生，分化の分子生物学的機序の解明は，1994年Fosterら^9）やWagnerら^23）により発表されたcampomelic dysplasia（屈曲肢異形成症）の原因遺伝子Sox9がブレイクスルーの第一歩となった．

参考文献

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