ABSTRACT
The aim of this study was the identification of specific proteomic profiles, related to a restored cystic fibrosis transmembrane conductance regulator (CFTR) activity in cystic fibrosis (CF) leukocytes before and after ex vivo treatment with the potentiator VX770. We used leukocytes, isolated from CF patients carrying residual function mutations and eligible for Ivacaftor therapy, and performed CFTR activity together with proteomic analyses through micro-LC-MS. Bioinformatic analyses of the results obtained revealed the downregulation of proteins belonging to the leukocyte transendothelial migration and regulation of actin cytoskeleton pathways when CFTR activity was rescued by VX770 treatment. In particular, we focused our attention on matrix metalloproteinase 9 (MMP9), because the high expression of this protease potentially contributes to parenchyma lung destruction and dysfunction in CF. Thus, the downregulation of MMP9 could represent one of the possible positive effects of VX770 in decreasing the disease progression, and a potential biomarker for the prediction of the efficacy of therapies targeting the defect of Cl- transport in CF.
Subject(s)
Aminophenols/pharmacology , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis/drug therapy , Matrix Metalloproteinase 9/genetics , Quinolones/pharmacology , Actin Cytoskeleton/genetics , Adult , Biomarkers/blood , Cell Movement/drug effects , Cystic Fibrosis/blood , Cystic Fibrosis/genetics , Cystic Fibrosis/pathology , Female , Gene Expression Regulation/drug effects , Humans , Leukocytes, Mononuclear/drug effects , Male , Proteome/geneticsABSTRACT
BACKGROUND: Acute recurrent pancreatitis (ARP) is characterized by episodes of acute pancreatitis in an otherwise normal gland. When no cause of ARP is identifiable, the diagnosis of "idiopathic" ARP is given. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene increase the risk of ARP by 3- to 4-times compared to the general population, while cystic fibrosis (CF) patients present with a 40- to 80-times higher risk of developing pancreatitis. CASE SUMMARY: In non-classical CF or CFTR-related disorders, CFTR functional tests can help to ensure a proper diagnosis. We applied an individualized combination of standardized and new CFTR functional bioassays for a patient referred to the Verona CF Center for evaluation after several episodes of acute pancreatitis. The CFTR genotype was G542X+/- with IVS8Tn:T7/9 polymorphism. The sweat (Cl-) values were borderline. Intestinal current measurements were performed according to the European Cystic Fibrosis Society Standardized Operating Procedure. Recent nasal surgery for deviated septum did not allow for nasal potential difference measurements. Lung function and sputum cultures were normal; azoospermia was excluded. Pancreas divisum was excluded by imaging but hypoplasia of the left hepatic lobe was detected. Innovative tests applied in this case include sweat rate measurement by image analysis, CFTR function in monocytes evaluated using a membrane potential-sensitive fluorescent probe, and the intestinal organoids forskolin-induced swelling assay. CONCLUSION: Combination of innovative CFTR functional assays might support a controversial diagnosis when CFTR-related disorders and/or non-classical CF are suspected.
