Optimizing the germfree mouse model for in vivo evaluation of oral Vibrio cholerae vaccine and vector strains

The germfree mouse model of Vibrio cholerae infection can be used to judge immune responses to V. cholerae vaccine and vector strains, In the original model, a single oral inoculation was administered on day 0, a booster oral inoculation was administered on day 14, and immune responses were analyzed with samples collected on day 28, Unfortunately, immune responses in this model frequently were low level, and interanimal variability occurred. In o rder to improve this model, we evaluated various primary and booster V. cho lerae inoculation schedules. The most prominent systemic and mucosal antibo dy responses were measured in mice that received a multiple primary inocula tion series on days 0, 2, 4, and 6 and booster inoculations on days 28 and 42, These modifications result in improved preliminary evaluation of ii. ch olerae vaccine and vector strains in mice.