5′-adenosine monophosphate mediated cooling treatment enhances ΔF508-Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) stability in vivo

Background: Gene mutations that produce misprocessed proteins are linked to many human disorders. Interestingly, some misprocessed proteins retained their biological function when stabilized by low temperature treatment of cultured cells in vitro. Here we investigate whether low temperature treatment in vivo can rescue misfolded proteins by applying 5'-AMP mediated whole body cooling to a Cystic Fibrosis (CF) mouse model carrying a mutant cystic fibrosis transmembrane conductance regulator (CFTR) with a deletion of the phenylalanine residue in position 508 (Delta F508-CFTR). Low temperature treatment of cultured cells was previously shown to be able to alleviate the processing defect of Delta F508-CFTR, enhancing its plasma membrane localization and its function in mediating chloride ion transport. Results: Here, we report that whole body cooling enhanced the retention of Delta F508-CFTR in intestinal epithelial cells. Functional analysis based on beta-adrenergic dependent salivary secretion and post-natal mortality rate revealed a moderate but significant improvement in treated compared with untreated CF mice. Conclusions: Our findings demonstrate that temperature sensitive processing of mutant proteins can be responsive to low temperature treatment in vivo.