Díaz-Flores Lucio, Gutiérrez Ricardo, Pino García Maria, González Miriam, Díaz-Flores Lucio, Francisco Madrid Juan
Departamento de Patología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain.
Curr Stem Cell Res Ther. 2016;11(5):395-403. doi: 10.2174/1574888x10666151001115111.
This review outlines the role of CD34+ stromal cells/telocytes (CD34+ SC/TCs) in repair and considers the following issues. Firstly, the conceptual aspects of repair, including regeneration and repair through granulation tissue (RTGT) as two types of repair, RTGT stages (inflammatory, proliferative, and remodeling), and tissue in repair as a substrate to assess the in vivo behavior of activated CD34+ SC/TCs. Subsequently, current knowledge of CD34+ SC/TCs, such as identification, characteristics, and functions, as well as possible stages (quiescent and activated) are taken into account. We then consider the role in regeneration of quiescent CD34+ SC/TCs (in unperturbed physiological conditions) as a nurse of stem cells (e.g., in the heart, skin, respiratory tree, gastrointestinal tract, liver, eye, and choroid plexus). Special attention is paid to the characteristics of activated CD34+ SC/TCs and the overlapping steps of activation with and without loss of CD34 expression and with and without gain of αSMA expression. With this contribution, we establish the role of CD34+ SC/TCs as progenitor cells and as a source of fibroblasts and myofibroblasts in repair through granulation tissue, fibrosis, and tumor stroma. Activated CD34+ SC/TCs in encapsulation and other processes (e.g., Reinke's edema, cutaneous myxoid cyst, mixomatous mitral valve degeneration, and fibrous papula of the face) are also outlined. Finally, similarities between modifications of CD34+ SC/TCs during in vivo activation and of multipotent mesenchymal stromal/stem cells in culture are examined in order to correlate the growing literature on CD34+ SC/TCs and the exponential research in cultured mesenchymal stromal/stem cells.
本综述概述了CD34+基质细胞/端细胞（CD34+ SC/TCs）在修复过程中的作用，并探讨了以下问题。首先，修复的概念层面，包括作为两种修复类型的再生和通过肉芽组织的修复（RTGT）、RTGT阶段（炎症期、增殖期和重塑期），以及将修复中的组织作为评估活化的CD34+ SC/TCs体内行为的底物。随后，考虑了关于CD34+ SC/TCs的现有知识，如识别、特征和功能，以及可能的阶段（静止期和活化期）。接着，我们探讨了静止的CD34+ SC/TCs（在未受干扰的生理条件下）作为干细胞的守护者在再生中的作用（例如在心脏、皮肤、呼吸道、胃肠道、肝脏、眼睛和脉络丛中）。特别关注活化的CD34+ SC/TCs的特征，以及活化过程中CD34表达有无缺失和αSMA表达有无增加的重叠步骤。通过本研究，我们确立了CD34+ SC/TCs作为祖细胞以及在通过肉芽组织、纤维化和肿瘤基质进行修复过程中作为成纤维细胞和肌成纤维细胞来源的作用。还概述了活化的CD34+ SC/TCs在包囊形成和其他过程（如Reinke水肿、皮肤黏液样囊肿、黏液瘤样二尖瓣退变和面部纤维丘疹）中的作用。最后，研究了体内活化过程中CD34+ SC/TCs的修饰与培养的多能间充质基质/干细胞的修饰之间的相似性，以便将关于CD34+ SC/TCs的不断增长的文献与培养的间充质基质/干细胞的指数级研究联系起来。
