Cretoiu Dragos, Gherghiceanu Mihaela, Hummel Eric, Zimmermann Hans, Simionescu Olga, Popescu Laurentiu M
Department of Cellular and Molecular Medicine, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Victor Babeș National Institute of Pathology, Bucharest, Romania.
J Cell Mol Med. 2015 Apr;19(4):714-22. doi: 10.1111/jcmm.12578.
We have shown in 2012 the existence of telocytes (TCs) in human dermis. TCs were described by transmission electron microscopy (TEM) as interstitial cells located in non-epithelial spaces (stroma) of many organs (see www.telocytes.com). TCs have very long prolongations (tens to hundreds micrometers) named Telopodes (Tps). These Tps have a special conformation with dilated portions named podoms (containing mitochondria, endoplasmic reticulum and caveolae) and very thin segments (below resolving power of light microscopy), called podomers. To show the real 3D architecture of TC network, we used the most advanced available electron microscope technology: focused ion beam scanning electron microscopy (FIB-SEM) tomography. Generally, 3D reconstruction of dermal TCs by FIB-SEM tomography revealed the existence of Tps with various conformations: (i) long, flattened irregular veils (ribbon-like segments) with knobs, corresponding to podoms, and (ii) tubular structures (podomers) with uneven calibre because of irregular dilations (knobs) - the podoms. FIB-SEM tomography also showed numerous extracellular vesicles (diameter 438.6 ± 149.1 nm, n = 30) released by a human dermal TC. Our data might be useful for understanding the role(s) of TCs in intercellular signalling and communication, as well as for comprehension of pathologies like scleroderma, multiple sclerosis, psoriasis, etc.
2012年我们已证实人真皮中存在端粒细胞（TCs）。通过透射电子显微镜（TEM），端粒细胞被描述为位于许多器官非上皮空间（基质）的间质细胞（见www.telocytes.com）。端粒细胞具有名为端粒足（Tps）的非常长的延伸部分（数十至数百微米）。这些端粒足具有特殊的构象，有名为podom的扩张部分（含有线粒体、内质网和小窝）以及非常细的部分（低于光学显微镜的分辨能力），称为podomer。为了展示端粒细胞网络的真实三维结构，我们使用了现有的最先进电子显微镜技术：聚焦离子束扫描电子显微镜（FIB-SEM）断层扫描。一般来说，通过FIB-SEM断层扫描对真皮端粒细胞进行三维重建揭示了具有各种构象的端粒足的存在：（i）带有瘤状结构（对应于podom）的长而扁平的不规则面纱状（带状段），以及（ii）由于不规则扩张（瘤状结构）——即podom——而管径不均匀的管状结构（podomer）。FIB-SEM断层扫描还显示了人真皮端粒细胞释放的大量细胞外囊泡（直径438.6±149.1纳米，n = 30）。我们的数据可能有助于理解端粒细胞在细胞间信号传导和通讯中的作用，以及有助于理解诸如硬皮病、多发性硬化症、牛皮癣等疾病。
