体外培养大鼠触须毛囊真皮鞘细胞的生物学特性及其超微结构

目的：探讨大鼠触须毛囊真皮鞘细胞体外培养生长特性和电镜下超微结构特征。方法：显微分离大鼠触须毛囊真皮鞘，组织块法原代培养获得真皮鞘细胞，免疫组化和免疫荧光染色进行细胞鉴定，MTT法测定细胞生长曲线，并通过扫描电镜和透射电镜观察其超微结构。结果：真皮鞘细胞原代培养5—7d仅有少量细胞由组织块中长出，培养14d方可传代。传代后细胞呈克隆样丛状生长，细胞丛相互连接呈网状，3～5d传一代，可连续传10代以上。扫描电镜见毛囊真皮鞘内有许多散在的纺锤形细胞，胞体丰满，表面不光滑，有较长的细胞突起。透射电镜下见细胞核大，富含常染色质，核仁明显，胞浆中细胞器少，胞膜下可见由细丝样结构组成的致密斑。结论：大鼠触须毛囊真皮鞘细胞原代生长迟缓，传代后细胞增殖旺盛，其超微结构特点提示该细胞分化程度较低，属于成体中较为幼稚的间充质细胞。

Biological characteristics and the ultrastructure of rat vibrissa follicle dermal sheath cells cultured in vitro

Objective:To investigate the biological characteristics and ultrastructural feature of rat vibrissa follicle dermal sheath cells cultured in vitro.Methods:The dermal sheaths were dissected from the vibrissa follicles of adult Wistar rat using microsurgical techniques.The dermal sheath cells were primarily cultured by the method of tissue adherence.The cells were identified by immunohistochemistry and immunofluorescence.The growth curve of this cell line was depicted by MTT assay.The ultrastructural features were observed by means of scanning electron microscope(SEM) and transmission(electron) microscope(TEM).Results:Five to seven days after cultured in vitro,only a few cells spreaded outwards from the dermal sheath explants.The primarily cultured cells could not be sub-cultured till 14 days.The cells grew as clone-like clusters.They were sub-cultured 3-5 days once and could be cultured serially for over 10 passages.SEM examination showed that the cells adhering on the dermal sheath looked like spindles with ovoid cell body and unsmooth surface.Under TEM,the cultured cells had a big nucleus with prominent nucleoli.The organelles in the cytoplasm were very scanty.Bundles of fine filament were noticed beneath the cytoplasmic membrane.Conclusion:The dermal sheath cells grow slowly in primary culture and proliferate quickly after subculture.The ultrastructural characteristics indicate that the dermal sheath cells of vibrissa follicle may be the mesenchymal cells with low differentiation in adult rat.