Tracking radioactive larvae ofStrongyloides rattiin the host

Abstract

SUMMARYInfective larvae of homogonicStrongyloides rattigrown in faecal culture with32P or75Se acquired a significant amount of radioactivity which was firmly attached to them. Heating removed most of the32P but left75Se in place. Subcutaneous injection of virgin and nursing mother rats with living and heat-killed radioactive larvae resulted in a pattern of labelling in the small intestine of injected animals and, in the case of75Se, those of suckling pups, which can only be explained if labelled worms follow the natural migratory routes. The use of this tool in migratory studies is discussed, with precautions to allow for flaws in the technique.