Supplementary Material for: New Description of Telocyte Sheaths in the Bovine Uterine Tube: An Immunohistochemical and Scanning Microscopic Study

Telocytes are a special type of interstitial cells characterized by distinctive cellular extensions with alternating thin segments (podomers) and dilations (podoms). Telocytes establish contact with various cells and structures, but their role in the regulation of the function of many cell types is still obscure. The aim of the current study was to investigate the morphology, histochemistry, and immunohistochemistry of telocytes, and their distribution, organization, and morphometric measurements in different layers of the adult bovine uterine tube. Telocytes showed positive immunostaining for CD117, S-100 protein, vimentin, desmin, α-smooth muscle actin, tubulin, laminin, estrogen receptor-α, and progesterone receptor. They were organized in different types of sheaths: subepithelial, inner/outer perimuscular, and intramuscular sheaths. Telocytes were scattered in the lamina propria, in the muscular layer, and the serosa. According to their size, they were grouped into different types of telocytes: small, large, and giant telocytes. Small telocytes were the most common type and located in all layers; large telocytes were observed in the epithelium, lamina propria, and inner/outer perimuscular and intramuscular sheaths, and giant telocytes were found in the external layer of the outer perimuscular sheath. Telocytes were connected by thin and thick telopodes (fenestrated membranes). Fenestrated membranes enabled connections between telocytes along the entire muscular wall of the uterine tube. Telocytes established an extensive biological network of different types of cells and structures, including epithelial, muscular, and mast cells, blood vessels, glomus, and nerve fibers. We hypothesize that telocytes help to organize the functional coordination between different types of cells in the uterine tube.Telocytes（Telocytes）是一类特殊的间质细胞，以具有交替细段（podomers）与膨大区（podoms）的独特细胞突起为标志性特征。该类细胞可与多种细胞及结构建立联系，但其对诸多细胞类型功能的调控作用仍不明确。本研究旨在探究成年牛输卵管各层中Telocytes的形态学、组织化学与免疫组织化学特征，以及其分布、排布方式与形态计量学参数。研究显示，Telocytes对CD117、S-100蛋白、波形蛋白、结蛋白、α-平滑肌肌动蛋白、微管蛋白、层粘连蛋白、雌激素受体α及孕激素受体呈阳性免疫染色。它们以多种鞘状结构排布：上皮下鞘、肌层内外周鞘及肌内鞘。Telocytes散在于固有层、肌层与浆膜层中。根据体积大小，Telocytes可分为三类：小型、大型与巨型Telocytes。其中小型Telocytes最为常见，分布于所有组织层；大型Telocytes可见于上皮、固有层、肌层内外周鞘及肌内鞘；巨型Telocytes则仅见于外周肌鞘的外层。Telocytes通过粗细不一的带窗孔膜结构的细胞突起（telopodes）相互连接。这种窗孔膜结构使得Telocytes能够沿输卵管整个肌壁建立相互联系。Telocytes可与多种细胞及结构构建广泛的生物网络，涵盖上皮细胞、肌细胞、肥大细胞、血管、血管球与神经纤维。本研究推测，Telocytes有助于协调输卵管内不同类型细胞间的功能协同。