Bile was collected from Kunming mice killed by anaesthetic
inhalation with isoflurane (Sigma) and stored at 280uC prior to
experimentation. For in vitro experiments, the muscle larvae were
activated by the mice bile (diluted 1:20 in saline) at 37uC for 2 h.
Then, the larvae were rinsed three times with saline, incubated for
2 h in saline plus antibiotics, and washed on a sieve before being
inoculated onto IEC monolayers [7].