caa a22 4500 386400393 CHVBK 20180307112156.0 cr unu---uuuuu 161130e198912 xx s 000 0 eng 10.1017/S0031182000059072 doi S0031182000059072 pii (NATIONALLICENCE)cambridge-10.1017/S0031182000059072 Variable generation of specific acquired resistance in CBA/Ca mice chronically infected with schistosomiasis mansoni [Elektronische Daten] Naive CBA/Ca mice and CBA/Ca mice infected 12 weeks previously with 20 normal cercariae of Schistosoma mansoni were challenged percutaneously with isotopically labelled parasites. Challenge worm migration was followed, in 5 separate experiments, by means of compressed organ autoradiography. In three experiments, 43.1 % of challenge parasites did not arrive in the lungs of infected mice on day 6 as compared to 7.7 % in naive controls, thereby indicating that pre-lung sites constitute the first barrier in resistance to reinfection. A further 15% of the challenge worm burden was lost in the lungs or en route to the liver in the immune animals, and portal perfusion revealed that 25.4% of the challenge was lost in the liver. Two other experiments revealed no comparable phases of pre-liver attrition however; instead resistance was only evident at final perfusion on days 28 or 35. These data reveal the variable generation of specific acquired immunity in mice harbouring a chronic schistosome infection and thus clarify current discrepancies in the literature. The results are discussed in relation to documented evidence for the nature of specific and non-specific immune mechanisms reported to operate at different sites in the infection model of schistosomiasis mansoni. Copyright © Cambridge University Press 1989 Schistosoma mansoni nationallicence chronic infection resistance nationallicence immune mechanisms nationallicence autoradiographic tracking nationallicence Delgado V. S. Division of Parasitology, National Institute for Medical Research, Mill Hill, London NW7 1AA Mclaren D. J. Division of Parasitology, National Institute for Medical Research, Mill Hill, London NW7 1AA Parasitology Cambridge University Press 99/3(1989-12), 357-364 0031-1820 99:3<357 1989 99 PAR https://doi.org/10.1017/S0031182000059072 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0031182000059072 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Delgado V. S. Division of Parasitology, National Institute for Medical Research, Mill Hill, London NW7 1AA NATIONALLICENCE 700 1- Mclaren D. J. Division of Parasitology, National Institute for Medical Research, Mill Hill, London NW7 1AA NATIONALLICENCE 773 0- Parasitology Cambridge University Press 99/3(1989-12), 357-364 0031-1820 99:3<357 1989 99 PAR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge