Comparison of ex vivo and in vitro intestinal cystic fibrosis models to measure CFTR-dependent ion channel activity.

Background: New functional assays using primary human intestinal adult stem cell cultures can be valuable tools to study epithelial defects in human diseases such as cystic fibrosis.

Methods: CFTR-mediated ion transport was measured in rectal organoid-derived monolayers grown from subjects with various CFTR mutations and compared to donor-matched intestinal current measurements (ICM) in rectal biopsies and forskolin-induced swelling of rectal organoids.

Results: Rectal organoid-derived monolayers were generated within four days. Ion transport measurements of CFTR function using these monolayers correlated with ICM and organoid swelling (r = 0.73 and 0.79 respectively). Culturing the monolayers under differentiation conditions enhanced the detection of mucus-secreting cells and was accompanied by reduced CFTR function.

Conclusions: CFTR-dependent intestinal epithelial ion transport properties can be measured in rectal organoid-derived monolayers of subjects and correlate with donor-matched ICM and rectal organoid swelling.