Development of Human Pancreatic Ductal Epithelial Cells as a model of Cystic Fibrosis Pancreatic Disease

Abstract

Impaired insulin release underlies the development of cystic-fibrosis-related diabetes (CFRD) which affects 40-50% of adults with CF and is associated with significantly increased morbidity and mortality. The initiating site of CF pancreas pathology is the pancreatic duct as CFTR expression is highest in pancreatic ductal epithelial cells (PDECs). While loss-of-function mutations in CFTR result in CF, these mutations lead to the destruction of pancreatic exocrine (acinar) tissue which is characterized by the clinical manifestation of pancreatic exocrine insufficiency in 85% of people with CF. Despite this destruction of the pancreas, there is only modest loss of islets. While the pathophysiology of CF pancreas disease and CFRD are not well understood, it is appreciated that paracrine signals in the PDEC-islet axis could be one mechanism contributing to the deficit in insulin release in CFRD. The data supporting the existence of crosstalk between PDECs and islets are limited in translational human models, despite the observation of their close proximity within the pancreas. The studies presented in this thesis represent an advancement in our tools to study this PDEC-islet axis. Collectively, the experiments enclosed in this thesis provides a better foundational understanding of ex vivo and cultured PDEC CFTR, SOX9, AQP1, KRT7 and KRT19 mRNA expression. Additionally, these findings represent advancement in developing a model to modulate CFTR expression in primary human PDECs. Ultimately, these discoveries set a path for downstream analysis that will prove valuable in the discovery and development of future therapeutics to treat CFRD.