TRANSCLCONDREG · Arylpyrrole-based Transmembrane Transporters for Induced Chloride Regulation in Cystic Fibrosis Epithelial Cells

The regulation of cellular ion concentrations is critical for a range of physiological processes. Malfunction of transmembrane Cl-/HCO3- antiport has been associated with cystic fibrosis and other channelopathies. Changes in pH via H+/Cl- symport cause deacidification of acidic organelles leading to cytoplasmic acidification, an early event in apoptosis. Synthetic anion transporters have been studied mainly in artificial vesicles for their ability to facilitate Cl-/HCO3- antiport and H+/Cl- symport. However, just recently it was shown that the most efficient transporters in liposome assays not always correlate to the most efficient conductors in live cell studies, most likely due to the differences between the model membrane used for the vesicle studies and the biological membranes present in cells. Therefore, a need has arisen for a systematic methodology to quantify the ability of synthetic compounds to facilitate transmembrane chloride transport in live cells. A set of prodigiosin-inspired transporter agents will be synthesized applying a newly discovered route towards 2,5-diarylpyrrole moieties. Their transmembrane anion conductor properties and pH dependency will be investigated first in unilamellar vesicle assays, to determine the transport mechanism. Further, the Ussing technique will be applied to quantify the transport efficiency in cystic fibrosis epithelial cells and to set up a systematic method for high throughput screening towards potential lead compounds in the quest against channel replacing therapies. Fluorescence in vitro cytotoxicity assays for a range of cancer cell lines will be performed and the compounds potency to introduce apoptosis will be determined.