Effect of an intraperitoneal injection with activated Hymenolepis nana and H. diminuta cysticercoids on homologous challenge.
The intraperitoneal injection of excysted-activated cysticercoids of Hymenolepis nana and H. diminuta stimulates a protective immunity in mice and rats against an oral homologous challenge with different levels of effectiveness. The immunizing dose reduced only worm growth in the natural host (i.e. H. nana/mouse and H. diminuta/rat models), while in the unnatural host (i.e. H. diminuta/mouse model) expulsion of the worms from the intestine was accelerated. In mice infected with H. nana the effect appeared about 20 days after injection, but a greater effect was found in both models 40 days later even at low dose (1 cysticercoid). In rats the effect appeared 40 days after injection when a large inoculum (50 or 100 cysticercoids) was used. The induced immunity was slow in developing and only partially effective: this was probably related to host difficulties in processing somatic worm antigens, or to the slow production of metabolites by the worms in the peritoneal cavity.
Istituto di Patologia Sperimentale, Facoltà di Medicina e Chirurgia, Università degli Studi di Cagliari.
F
F
Gabriele
G
G
Bortoletti
M
M
Conchedda
C
C
Palmas
D000818:Animals; D006925:Hymenolepiasis / Q000469:parasitology / Q000628:therapy*; D006926:Hymenolepis / Q000254:growth & development / Q000276:immunology*; D016233:Immunotherapy, Active; D007274:Injections, Intraperitoneal; D007411:Intestinal Diseases, Parasitic / Q000469:parasitology / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D051381:Rats; D017208:Rats, Wistar