Early Pathogenesis of Cystic Fibrosis Related Diabetes

1 项目概要 2 囊性纤维化 (CF) 是白种人群体中最常见的致死性常染色体隐性遗传病， 3 由囊性纤维化电导调节因子 (CFTR) 氯离子通道缺陷引起。 CF是多器官 4 影响肺、胰腺、肝、肠和胆囊的疾病。囊性纤维化相关糖尿病（CFRD）是 5 CF最常见的严重并发症，与发病率和死亡率增加相关。 CFRD, 6 其病理生理学不同于 1 型和 2 型糖尿病，显着恶化营养和 7 CF患者的肺部健康状况。我们对 CF 雪貂和 3 个月至 6 岁儿童的研究表明： 8 CFRD 的基础发生在生命早期，此时腺泡细胞丢失并且发生炎症/纤维化重塑 9 发生。在 CF 雪貂中，这种外分泌驱动的胰腺重塑会导致 b 细胞损失引起的血糖危机 10和/或功能障碍。有趣的是，CF 雪貂中新形成的 b 细胞的出现与短暂的 11 血糖控制恢复。尽管如此，那些早期血糖紊乱最严重的 CF 雪貂 12 在以后的生活中发展CFRD。我们还报道了类似的血糖紊乱模式 13 恢复发生在年幼的 CF 儿童中。我们的中心假设提出 CF 雪貂胰腺中的新 b 细胞 14个源自外分泌祖细胞和/或定向去分化b细胞。三系血统追踪雪貂 15 个模型将用于绘制 b 细胞祖细胞 (INS-IRES-CreERT2)、导管源性内分泌祖细胞的命运图谱 16 (KRT7-IRES-CreERT2) 和腺泡衍生的内分泌祖细胞 (PTF1A-IRES-CreERT2)。使用额外的 17 CFTRG551D 雪貂模型，使用 CFTR 调节器提供对胰腺疾病发作的时间控制 18 VX-770，将允许剖析胰腺炎的发育时间如何影响祖细胞状态 19 以及 CFRD 的长期进展。我们的体内和体外初步数据也表明，CF 雪貂导管 20 个细胞获得与胰腺祖细胞中发现的转录和表观遗传状态一致的特性 21 开发期间。将通过使用体外模型和研究来研究这种改变的机制 CF 雪貂胰腺在子宫内发育期间的胰腺祖细胞规范的 22。拟议的 23 研究汇集了两家在 CF 胰腺疾病动物模型方面具有专业知识的机构， 24 胰岛内分泌前体的谱系追踪，以及 CFRD 的综合生理学来描述其机制 使用第一个非啮齿类动物谱系追踪模型使 CF 中的 25 胰岛复活。这些研究预计将 26 确定的机制不仅与 CFRD 相关，而且还与其他形式的胰源性糖尿病相关。

1 Project Summary 2 Cystic Fibrosis (CF) is the most common lethal autosomal recessive disorder in Caucasian populations and is 3 caused by defects in the cystic fibrosis conductance regulator (CFTR) chloride channel. CF is a multi-organ 4 disease affecting the lung, pancreas, liver, intestine, and gallbladder. Cystic fibrosis related diabetes (CFRD) is 5 the most common severe complication of CF and is associated with increased morbidity and mortality. CFRD, 6 which is pathophysiologically distinct from type 1 and type 2 diabetes, significantly worsens the nutritional and 7 pulmonary health of CF patients. Our studies in CF ferrets and children 3 months to 6 years of age suggest that 8 the underpinnings of CFRD occur very early in life when acinar cells are lost and inflammatory/fibrotic remodeling 9 occurs. In CF ferrets, this exocrine-driven pancreatic remodeling leads to a glycemic crisis caused by b-cell loss 10 and/or dysfunction. Interestingly, the emergence of newly formed b-cells in CF ferrets coincides with a transient 11 recovery in glycemic control. Nonetheless, those CF ferrets with the greatest early-life glycemic disturbances go 12 on to develop CFRD later in life. We have also reported that a similar pattern of glycemic disturbance and 13 recovery occurs in young CF children. Our central hypothesis proposes that new b-cells in the CF ferret pancreas 14 are derived from exocrine progenitors and/or committed dedifferentiated b-cells. Three lineage tracing ferret 15 models will be used to fate map b-cell progenitors (INS-IRES-CreERT2), ductal-derived endocrine progenitors 16 (KRT7-IRES-CreERT2), and acinar-derived endocrine progenitors (PTF1A-IRES-CreERT2). The use of an additional 17 CFTRG551D ferret model, which affords temporal control of pancreatic disease onset using the CFTR modulator 18 VX-770, will allow for dissection of how the developmental timing of pancreatitis impact progenitor cell states 19 and longer-term progression of CFRD. Our in vivo and in vitro preliminary data also show that CF ferret ductal 20 cells acquire properties consistent with the transcriptional and epigenetic states found in pancreatic progenitors 21 during development. The mechanisms of this alteration will be investigated by using in vitro models and the study 22 of pancreatic progenitor cell specification during in utero development of the CF ferret pancreas. The proposed 23 research has brought together two institutions with expertise in animal modeling of CF pancreatic disease, 24 lineage-tracing of islet endocrine precursors, and integrated physiology of CFRD to delineate the mechanism of 25 islet resurgence in CF using the first ever non-rodent lineage-tracing models. These studies are expected to 26 identify mechanisms not only relevant to CFRD, but also other forms of pancreatogenic diabetes.