Novel diagnostic and therapeutic opportunities for Cystic Fibrosis

Abstract

Cystic fibrosis (CF) is the most common life-shortening rare disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which was identified in 1989. The CFTR gene encodes a 3’,5’-cyclic adenosine monophosphate (cAMP)-activated transmembrane anion channel and mutations herein disturb ion transport at the apical membrane, mainly of mucosal surfaces. CF is a multi-organ disease due to widespread expression of the CFTR protein in the upper and lower airways, pancreas, bile ducts, gastrointestinal tract, vas deferens, sweat glands, some immune cells, and other tissues. Patients experience many different symptoms such as intestinal obstruction, malnutrition, infertility, salty sweat, but most ultimately succumb to recurrent lung infections and associated inflammation and tissue damage. Currently, the median life expectancy for newborn CF-patients, with the most common disease causing mutation, was estimated in 2010 at 37 years. This scope of this thesis is to develop new methods that can assist the development of new CFTR modulators, and the application of such modulators in a more personalized setting. Chapter 2 describes the development of a novel YFP fusion protein with enhanced potential for high throughput screening. Chapter 3 shows how intestinal organoids can be used for analysis of drugs affecting premature termination codon readthrough. In Chapter 4, we develop methodology that can be used to quantitate circulating levels of CFTR modulators in plasma. Chapter 5 indicates that intestinal organoids can be used to screen small drug libraries for their potential to activate CFTR in vitro and in vivo. In chapter 6, we sought to identify inflammatory modulators that may regulate CFTR expression and function. Chapter 7 provides a discussion of chapters 2-6.