Farinha et al. used heterologous CHO cells where CFTR (wild type or ΔF508) was overexpressed, while others (Rubenstein et al., 1997; Choo-Kang and Zeitlin, 2001; Suaud et al., 2011b) used IB3-1 CF bronchiolar epithelial cells where ΔF508-CFTR is endogenously expressed. Here, CFTR is linked to cystic fibrosis.