Infective mesocercarial development of Neodiplostomum seoulense cercariae in an in vitro culture system

초록

Neodiplostomum seoulense is an intestinal tremade of humans and rodents in Korea. For mesocercarial development, the cercariae of N. seoulense use the tadpole of Rana nigromaculata as a second intermediate in their natural life cycle. In this study, N. seoulense cercariae were successfully cultured to infective mesocercariae. The cercariae were collected from experimentally infected Hippeutis cantori snails. The artificial detachment of a cercarial tail was induced by 5-times fine needle passage. The separated cercarial heads were cultured in medium 199 contained 10% fetal bovine serum and 1% antibiotics solution. After 14 days, the 3% rat blood was added to the media, and the culture was continued to 60 days. In viability tests, the mesocercariae cultured for 45 and more days successfully matured to adult worms in experimentally infected rats. In stool examination, the eggs were detected from day 11 post infection. Fully developed adult worms were able to be recovered from day 14 post infection. This culture system can be adapted for additional studies on the N. seoulense life cycle, especially to supply large numbers of mesocercriae for other studies.