Disease Outcome Subsequent to Primary and Secondary Urogenital Infection with Murine or Human Biovars of

A susceptible strain of mice infected intravaginally with the mouse pneumonitis biovar of Chlamydia trachomatis became infertile and sustained high rates of hydrosalpinx formation regardless of prior infection with a human serovar. Conversely, susceptible mice infected with human serovars remained fertile unless challenged with a homologous human serovar. It is a widely held paradigm that protection against infection with Chlamydia trachomatis is conferred by serovar-specific epitopes but that cross-reactive genus-specific epitopes elicit hypersensitizing responses (2, 8, 17). This theory is supported by experimental human conjunctivitis studies (7), previous hu-man vaccine trials (6, 18), nonhuman primate models (10), and in vitro antibody neutralization experiments (1, 2, 17). How-ever, using a common murine model, we have previously found that primary infection with the mouse pneumonitis biovar of C. trachomatis (MoPn) not only yielded protection against homo-typic MoPn challenge but also provided significant protectio