When transplanted into Hannah, the stem cells automatically picked up the body's signals and got transformed into epithelial cells, the kind found in any trachea.
However, both Collins and this reviewer are wrong as people studying FTI effects on colorectal cancer routinely use noninvasive cheek swabs and perform immunfluorescnce microscopy on the recovered epithelial cells to determine the degree to which the FTIs are inhibiting prelamin A processing.
In my lab days, I always wondered about the wisdom of using nonoxynol-9 as a spermatocide because we used to use a related compound, octoxynol-9 (better known to labbies as Triton X-100), to break open human epithelial cancer cells to examine the proteins inside them.