A mouse model of bacterial vaginosis established by infecting estrogen-treated mice with Prevotella bivia

Objective To establish a mouse model of bacterial vaginosis (BV) by infecting estrogen-treated mice with Prevotella bivia (P.bivia). Methods The mice were intraperitoneally injected with beta-estradiol 17 valerate which was suspended in sesame oil and then inoculated with different doses of P. bivia strains at the logarithmic phase. Samples of vaginal flushing fluid were collected at different time points after inoculation and used for the isolation of P. bivia strains and the detection of sialidase activities. Altogether 30 mice treated with estrogen and high dose of P. bivia were killed on days 2, 7 and 21 (n=10). Samples of cornua uteri, bladder and kidney were collected from those mice for P. bivia strains isolation. Results Injection the estrogen-treated mice with P. bivia via vagina could cause the P. bivia infection for more than 14 days. The numbers of P. bivia strains isolated on day 21 decreased significantly. Enhanced sialidase activities and clue cells were observed in vaginal secretions of mice with P. bivia infection. Injection of mice with the high dose of P. bivia could spread the infection to cornua uteri. Conclusion Estrogen-treated mice could be used as an animal model for researches on BV. Key words: Bacterial vaginosis; Prevotella; Beta-estradiol 17 valerate; Sialidase activity; Mouse model