title: Effect of silica treatment on resistance to Babesia rodhaini infection in immunized mice.
abstract: The effect of silica treatment on the course of Babesia rodhaini infection was investigated in ICR mice pretreated with either a mixture of B. rodhaini parasitized red blood cell hemolysation-sonication (S) antigen and Propionibacterium acnes bacterin or P. acnes bacterin alone and not subjected to immunization. In the normal mice (non-immunized), the mean survival time was decreased by approximately 1 day when 5 mg per mouse of silica were intraperitoneally inoculated at 5 h before infection. In immunization with S antigen and P. acnes bacterin, all mice survived regardless of the dose of silica (15-25 mg per mouse) treatment. In contrast, in immunization with P. acnes bacterin alone, 3/10, 4/10 and 1/10 mice died of B. rodhaini, when inoculated with 15 mg per mouse, 20 mg per mouse and 25 mg per mouse of silica treatment 5 h before infection, respectively. These results suggest that peritoneal macrophages (M luminal diameter of), especially when activated non-specifically by P. acnes bacterin, play an important role in inhibiting multiplication of organisms at the early stage of infection and the mice immunized with S antigen were ready to quickly acquire an enhanced solid specific protection even if the function of M luminal diameter of was damaged by a high dose of silica treatment.
authors.affiliation: Department of Veterinary Parasitology, Nippon Veterinary and Animal Science University, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Saeki
authors.forename: T
authors.initials: T
authors.lastname: Ishii
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000276:immunology; D001403:Babesia / Q000276:immunology; D001404:Babesiosis / Q000276:immunology* / Q000517:prevention & control; D001428:Bacterial Vaccines / Q000276:immunology; D004912:Erythrocytes / Q000469:parasitology; D006461:Hemolysis; D007114:Immunization; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008813:Mice, Inbred ICR; D011425:Propionibacterium acnes / Q000276:immunology; D016052:Protozoan Vaccines; D012822:Silicon Dioxide / Q000494:pharmacology*
chemical_list: D000953:Antigens, Protozoan; D001428:Bacterial Vaccines; D016052:Protozoan Vaccines; D012822:Silicon Dioxide