Understanding the role of adult perivascular progenitors in vascular homeostasis, sclerosis and calcification in chronic kidney disease.

血管硬化和动脉钙化是慢性和终末期肾脏疾病（CKD/ESRD）心血管发病率和死亡率增加的主要原因。最近的数据，包括我们自己的数据，表明参与了常驻血管间充质干细胞（MSC）。我们已经确定Gli1， Hedgehog （Hh）通路的转录激活因子在血管周围MSC群体中特异性表达。我们已经证明这些Gli1+细胞是实体器官损伤后关键的肌成纤维细胞祖细胞，我们的初步数据表明这些细胞参与血管硬化。我们假设Gli1+细胞在血管壁的稳态中很重要，可能在急性损伤后的修复中作为祖细胞，但在慢性损伤（如CKD）中，通过肌成纤维细胞和成骨细胞型细胞的分化引发血管硬化和钙化。因此，我们将利用遗传命运追踪技术来阐明这一祖群体在体内平衡、急性损伤和CKD血管疾病中的作用。此外，我们将研究细胞特异性消融Gli1祖细胞是否会改变血管表型，改善甚至逆转小鼠血管硬化和钙化过程。我们的数据指向了人类中类似的细胞群。我们将在稳态和血管疾病中描述这种细胞群，我们将利用整个人类动脉环培养模型来了解这些祖细胞在血管钙化过程中的作用。此外，我们将利用CRISPR/Cas9介导的基因组工程在人体组织中开发一种命运追踪技术来进行克隆分析，并回答祖细胞群体在疾病建模和钙化过程中是否会扩张和分化的问题。我们假设规范和非规范Hh信号参与了血管钙化过程中的自我更新、招募和扩张。我们将利用CRISPR/Cas9介导的基因组编辑和药理学调节来全面评估Hh通路在小鼠和人类外体细胞稳态和疾病中的作用。

Vascular sclerosis and arterial calcification contribute centrally to increased cardiovascular morbidity and mortality in chronic and end-stage renal disease (CKD/ESRD). Recent data including our own suggest the involvement of resident vascular mesenchymal stem cells (MSC).We have identified that Gli1, a transcriptional activator of the Hedgehog (Hh) pathway is specifically expressed in a perivascular MSC population. We have demonstrated that these Gli1+ cells are key myofibroblast progenitors after injury of solid organs and our preliminary data point towards an involvement of these cells in vascular sclerosis. We are hypothesizing that Gli1+ cells are important in homeostasis of the vascular wall and might serve as progenitors in repair after acute injury, but trigger vascular sclerosis and calcification in chronic injury as in CKD by differentiation in myofibroblasts and osteoblasts-type cells . Thus, we will utilize genetic fate tracing techniques to elucidate the role of this progenitor population in homeostasis, acute injury and CKD vascular disease. Furthermore, we will study whether cell-specific ablation of Gli1 progenitors alters the vascular phenotype and ameliorates or even reverses the vascular sclerosis and calcification process in mice. Our data point towards a similar cell-population in humans. We will characterize this cell-population in homeostasis and vascular disease and we will utilize whole human artery ring culture models to understand the role of these progenitors during vascular calcification. Furthermore, we will develop a fate tracing technique in human tissue using CRISPR/Cas9 mediated genome engineering to perform clonal analysis and answer the question whether the Progenitor population expands and differentiates during disease modelling and calcification.We hypothesize that canonical and non-canonical Hh signaling is involved in self-renewal, recruitment and expansion during vascular calcification. We will utilize CRISPR/Cas9 mediated genome editing and pharmacologic modulation to comprehensively assess the role of the Hh pathway in adventitial progenitors of mice and humans during homeostasis and disease.