Finally, the main proteins regulated by Vav3 in CF, namely fibronectin and β1 integrin (Supplemental Figure 4A), or the transepithelial electrical resistance (TEER) — an indicator of epithelial integrity of polarized Calu-3 (Supplemental Figure 4C) — were not altered by TTPOE. This evidence concerns the gene FN1 and cystic fibrosis.