Braden Brian P, Taketa Daryl A, Pierce James D, Kassmer Susannah, Lewis Daniel D, De Tomaso Anthony W
Department of Molecular, Cellular, Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America.
PLoS One. 2014 Apr 15;9(4):e95460. doi: 10.1371/journal.pone.0095460. eCollection 2014.
The source of tissue turnover during homeostasis or following injury is usually due to proliferation of a small number of resident, lineage-restricted stem cells that have the ability to amplify and differentiate into mature cell types. We are studying vascular regeneration in a chordate model organism, Botryllus schlosseri, and have previously found that following surgical ablation of the extracorporeal vasculature, new tissue will regenerate in a VEGF-dependent process within 48 hrs. Here we use a novel vascular cell lineage tracing methodology to assess regeneration in parabiosed individuals and demonstrate that the source of regenerated vasculature is due to the proliferation of pre-existing vascular resident cells and not a mobile progenitor. We also show that these cells are bi-potential, and can reversibly adopt two fates, that of the newly forming vessels or the differentiated vascular tissue at the terminus of the vasculature, known as ampullae. In addition, we show that pre-existing vascular resident cells differentially express progenitor and differentiated cell markers including the Botryllus homologs of CD133, VEGFR-2, and Cadherin during the regenerative process.
在稳态或损伤后组织更新的来源通常是少数驻留的、谱系受限的干细胞增殖，这些干细胞能够扩增并分化为成熟细胞类型。我们正在研究一种脊索动物模式生物——柄海鞘中的血管再生，并且之前已经发现，在体外血管系统进行手术切除后，新组织将在48小时内通过依赖VEGF的过程再生。在这里，我们使用一种新型的血管细胞谱系追踪方法来评估联体个体中的再生，并证明再生血管系统的来源是由于预先存在的血管驻留细胞的增殖，而不是可移动的祖细胞。我们还表明，这些细胞具有双潜能，并且可以可逆地采用两种命运，即新形成血管的命运或血管末端分化的血管组织（称为壶腹）的命运。此外，我们表明，在再生过程中，预先存在的血管驻留细胞差异表达祖细胞和分化细胞标记，包括CD133、VEGFR-2和钙黏蛋白的柄海鞘同源物。
