The migratory pattern and attrition of<sup>75</sup>Se-labelled S.mansoni challenge cercariae in CF1mice immunized 0,1,3, or 5 times with 12kR-or 48kR-irradiated cercariae were investigatedby compressed org...The migratory pattern and attrition of<sup>75</sup>Se-labelled S.mansoni challenge cercariae in CF1mice immunized 0,1,3, or 5 times with 12kR-or 48kR-irradiated cercariae were investigatedby compressed organ autoradiography.Mice were percutaneously inoculated with 500-1000 cer-cariae for each immunization and with a known count of approximately 90 cercariae at adifferent site for challenge.The skin,lungs,liver,other organs,and catrcass were processedfor autoradiography.Hepatic and mesenteric perfusions for worm collection were alsosampled from day 19 through 34.In naive tnice,25% of challenge cercariae died in theskin.Skin attrition of challenge cercariae in mice immunized with 12kR-irradiated cercariaewas 43% with 1 immunization,54% with 3,and 58% with 5,whereas in mice immunized with48kR-irradiated cercariae,skin,attrition was48% with 1,63% with 3,and 76% with 5 immunni-zations.In all immunized mice,a high percentage of migrating sehistosomula died in the skinwithin 24 hours of a challenge infection.Utilizing autoradiography,it was found that thesilver foci created by single labelled worms were difficult to differentiate from those of pairedworms.This study documents the induction of acquired resistance against a challenge infectionin the skin by vaccination with highly irradiated cercariae,with the degree of attemtation ofimmunizing cercariae and the number of immunizations being closely related to the attritiotn.rate in the skin.Finally,we discuss the contradictory views concerning the site of attritiotn ofchallenge cercariae.展开更多
文摘The migratory pattern and attrition of<sup>75</sup>Se-labelled S.mansoni challenge cercariae in CF1mice immunized 0,1,3, or 5 times with 12kR-or 48kR-irradiated cercariae were investigatedby compressed organ autoradiography.Mice were percutaneously inoculated with 500-1000 cer-cariae for each immunization and with a known count of approximately 90 cercariae at adifferent site for challenge.The skin,lungs,liver,other organs,and catrcass were processedfor autoradiography.Hepatic and mesenteric perfusions for worm collection were alsosampled from day 19 through 34.In naive tnice,25% of challenge cercariae died in theskin.Skin attrition of challenge cercariae in mice immunized with 12kR-irradiated cercariaewas 43% with 1 immunization,54% with 3,and 58% with 5,whereas in mice immunized with48kR-irradiated cercariae,skin,attrition was48% with 1,63% with 3,and 76% with 5 immunni-zations.In all immunized mice,a high percentage of migrating sehistosomula died in the skinwithin 24 hours of a challenge infection.Utilizing autoradiography,it was found that thesilver foci created by single labelled worms were difficult to differentiate from those of pairedworms.This study documents the induction of acquired resistance against a challenge infectionin the skin by vaccination with highly irradiated cercariae,with the degree of attemtation ofimmunizing cercariae and the number of immunizations being closely related to the attritiotn.rate in the skin.Finally,we discuss the contradictory views concerning the site of attritiotn ofchallenge cercariae.
