Ian Thornell, PhD, Research Assistant Professor, received a two-year, $120,370 grant from the Gilead Sciences Research Scholars Program in Cystic Fibrosis to examine chloride secretion in cells directly and indirectly affected by the disease.

Genetic mutations in cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel in the membrane of the airway epithelia, causes cystic fibrosis. CFTR is not equally expressed in all cells in airway epithelia, and recent research shows that more than half of the CFTR in the airway is expressed in ionocyte cells alone.

“However, ionocytes are rare, less than 2% of epithelial cells,” Thornell said, “It remains unclear whether chloride secretion is achieved through single cells or through networks consisting of different cell types. We will test the hypothesis that optimal chloride secretion is achieved by epithelial cells networked together by intercellular channels called gap junctions.”

Michael Welsh, MD, professor in Pulmonary, Critical Care, and Occupational Medicine, serves as Thornell’s mentor on the project. Thornell and Welsh will test if chloride enters cells that do not have CFTR and travels through gap junctions to CFTR-expressing cells like ionocytes.

“Findings from this study will extend our understanding of airway chloride secretion and inform cystic fibrosis gene therapy as to which cell or cells need to be targeted,” Thornell said.