Susceptibility differences to Cryptosporidium parvum infection in two strains of gamma interferon knockout mice

• Published in: The Journal of parasitology Vol. 84; no. 5; pp. 1045 - 1048
• Main Authors: Mead, J.R, You, X.D
• Format: Journal Article
• Language: English
• Published: Lawrence, KS American Society of Parasitologists 01-10-1998
• Subjects: Animals; application rate; Biological and medical sciences; biological resistance; Black bears; Cattle; Cryptosporidiosis - immunology; Cryptosporidium parvum; disease resistance; Disease Susceptibility; Experimental protozoal diseases and models; Feces - parasitology; Foodborne illnesses; Harps; Immunity; infection; Infections; Infectious diseases; Interferon-gamma - genetics; Interferon-gamma - physiology; Interferons; Male; Medical sciences; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; mortality; mutants; Oocysts; Parasites; Parasitic diseases; Parasitism; Parasitology; Protozoal diseases; Research Notes; virulence; Protozoa; Host parasite relation; Apicomplexa; Protozoal disease; Genetic variability; Rodentia; Weight loss; Transgenic animal; Host; Parasitosis; Strain; Infection; Cryptosporidiosis; Vertebrata; Mammalia; Sensitivity resistance; Cryptosporidium parvum; Mouse; Deletion; Parasitism rate; Kinetics; Gamma interferon
• ISSN: 0022-3395; 1937-2345
• DOI: 10.2307/3284643

Differences in susceptibility to cryptosporidial infections were investigated between 2 strains of gamma interferon knockout (GKO) mice. Male C57BL/6J-Ifgtml@ and BALB/c-Ifgtml@ (GKO) mice, ages 8-10 wk, were inoculated with infectious oocysts at various doses. C57BL/6J-Ifgtml@ mice developed overwhelming infections and died 9-12 days after infection. Low inoculum doses (1 × 103) did not increase the survival time significantly. The infection intensity in C57BL/6J-Ifgtml@ mice inoculated with 1 × 105 oocysts/mouse increased markedly on day 4 postinfection (PI) and continued to increase significantly over the next 6-7 days. Most of the C57BL/6J-Ifgtml@ mice exceeded 15% weight loss and died by day 10 PI. In contrast, BALB/c-Ifgtml@ mice developed moderate infections from which they recovered. The average parasite load in the BALB/c-Ifgtml@ mice was 100 times lower than in C57BL/6J-Ifgtml@ mice. Mice survived until termination of the experiment (39 days) even when 1 × 106 oocysts per mouse were used for inoculation. BALB/c-Ifgtml@ mice did not exhibit significant weight loss (or difference in stool consistency). These 2 mouse strains make excellent models for studying differences in recovering and nonrecovering immune mechanisms.