Krahl Dieter, Sellheyer Klaus
Institut für Dermatohistologie, Heidelberg, Germany.
J Cutan Pathol. 2010 Mar;37(3):350-6. doi: 10.1111/j.1600-0560.2009.01369.x. Epub 2009 Jul 15.
The sex-determining gene Sox9 was recently unexpectedly found to have an essential role in outer root sheath differentiation. It was also characterized as a general marker of basal cell carcinoma. Herein, we describe its spatiotemporal expression pattern outside the hair follicle during human cutaneous embryogenesis.
We examined immunohistochemically samples from embryonic and fetal human skin for the expression of SOX9 using standard techniques. For comparison reasons, we also included scalp skin from adults.
SOX9 is expressed in the developing nail organ, eccrine glands, blood vessels and melanocytes/melanoblasts. In the nail organ, the nail bed but not the nail matrix was immunoreactive for SOX9. In plantar skin, SOX9 specifically labels the evolving eccrine glands but not the interfollicular keratinocytes.
The distinctive expression pattern of SOX9 during human cutaneous embryogenesis indicates a key role in skin homeostasis that includes but goes beyond its role in outer root sheath differentiation. Studying immunohistochemical markers in developing human skin has the potential to further our understanding of adult skin physiology and to deepen our concepts especially of the histogenesis of adnexal tumors (including those of the nail unit) and the relationship of the various adnexal structures to each other.
性别决定基因Sox9最近意外地被发现在外根鞘分化中起关键作用。它还被表征为基底细胞癌的通用标志物。在此，我们描述了其在人类皮肤胚胎发生过程中毛囊外的时空表达模式。
我们使用标准技术对来自胚胎和胎儿人类皮肤的样本进行免疫组织化学检测，以检测SOX9的表达。出于比较目的，我们还纳入了成人头皮皮肤。
SOX9在发育中的甲器官、汗腺、血管和黑素细胞/成黑素细胞中表达。在甲器官中，甲床而非甲母质对SOX9呈免疫反应性。在足底皮肤中，SOX9特异性标记正在发育的汗腺而非毛囊间角质形成细胞。
SOX9在人类皮肤胚胎发生过程中的独特表达模式表明其在皮肤稳态中起关键作用，这包括但不限于其在外根鞘分化中的作用。研究发育中的人类皮肤中的免疫组织化学标志物有可能增进我们对成人皮肤生理学的理解，并加深我们对附属器肿瘤（包括甲单位肿瘤）的组织发生以及各种附属器结构之间关系的认识。
