Accession Number : ADA265562


Title :   Evidence That Both Normal and Immune Elimination of Schistosoma mansoni Take Place at the Lung Stage of Migration Prior to Parasite Death


Corporate Author : NAVAL MEDICAL RESEARCH UNIT NO 3 FPO NEW YORK 09527


Personal Author(s) : Dean, David A ; Mangold, Beverly L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a265562.pdf


Report Date : Jan 1992


Pagination or Media Count : 13


Abstract : The number and distribution of autoradiographic foci observed in this and previous studies following percutaneous infection with 75Se-labeled Schistosoma mansoni cercariae indicate that the lungs are the principal site of worm elimination in both normal mice and mice immunized with irradiated cercariae. It was observed in the present study, however, that the intensities of the autoradiographic foci produced in the lungs during both the normal (early) and immune (late) phases of elimination were identical to those of foci produced in the livers of the same mice by larvae. shown to be alive. In contrast, foci produced in the lungs by heat-killed, intravenously injected, lung schistosomula became smaller and fainter with time, disappearing completely between seven and 10 days after injection in normal mice and between four and six days in immunized mice. These results indicate that although the targets of both normal and immune elimination do not proceed beyond the lung stage of migration, they do not die in the lungs. A possible explanation for this paradoxical situation, for which there is some experimental evidence, is that unsuccessful migrators leave the blood stream, enter alveoli, pass up the trachea, and are eventually digested in the gastrointestinal tract or eliminated from the body intact.


Descriptors :   *IMMUNITY , *SCHISTOSOMA MANSONI , *AUTORADIOGRAPHY , INJECTION , LUNG , MIGRATION , PHYSIOLOGY , BODIES , PARASITIC DISEASES , CERCARIAE , TRACHEA , ALVEOLI , WORMS , BLOOD , ELIMINATION , EXPOSURE(PHYSIOLOGY) , INFECTIOUS DISEASES , MEDICAL RESEARCH


Subject Categories : Medicine and Medical Research


Distribution Statement : APPROVED FOR PUBLIC RELEASE