Differences in adult Schistosoma mansoni worm burden requirements for the establishment of resistance to reinfection in inbred mice. I. CBA/J and C57BL/6 mice.
Schistosoma mansoni infections of CBA/J and C57BL/6 mice provided the hosts with partial protection against reinfection by S. mansoni cercariae. The level of protection, assayed by perfusion 21-25 days after challenge, varied over the course of infection. After patency the degree of resistance observed in CBA/J mice was related to the adult worm burden harbored by the mice. The same was initially true in C57BL/6 mice. Those C57BL/6 mice which lived until a chronic state of infection were rarely well protected and harbored few female worms. Strain differences were also apparent in that the number of worms required by C57BL/6 mice to establish the same level of protection as CBA/J mice was double that needed by CBA/J mice. Measurements were made of the newly formed egg-induced hepatic granulomas throughout the infection period (up to 30 weeks after infection). The data revealed that although the pattern by which C57BL/6 mice developed maximum granuloma formation and subsequent modulation was identical to that observed in CBA/J mice, C57BL/6 granulomas were consistently half the volume of their counterpart lesions in CBA/J mice.
D000818:Animals; D005260:Female; D006790:Host-Parasite Interactions; D007110:Immunity, Active; D008109:Liver Diseases, Parasitic / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010063:Ovum / Q000276:immunology; D012008:Recurrence; D012550:Schistosoma mansoni / Q000276:immunology; D012552:Schistosomiasis / Q000276:immunology*