Construction And Identification Of A Mice Model Of Bacterial Vaginosis

【Objective】To compare multiple indicators of the mice bacterial vaginosis（BV）model caused by Gardnerella vaginalis（GV）and common bacterial flora infection,to find a mice BV model suitable for clinical experiments.【Method】1.Clinical trial: 10 typical patients with BV who visited the gynecological outpatient department of the First Affiliated Hospital of Dali University from October2019 to February 2020 were collected as the clinical group,whose vaginal secretions were collected for rapid sialidase detection,ammoniacal Experiment and p H measurement.2.Animal trial: 60 mature female KM mice in the same batch and living in the same environment were randomly divided into control group（Group A,without any treatment）and experimental group.10 in each group,lavaging once a day and for a total of 6 days,the experimental group was divided into Group B（sterile PBS solution treatment）,Group C（Staphylococcus aureus + Escherichia coli mixed lavage）,Group D（Staphylococcus aureus + Escherichia coli + Streptococcus agalactiae mixed lavage）,Group E（Staphylococcus aureus + Escherichia coli + β-Hemolytic streptococcus mixed lavage）,Group F（Gardnerella vaginalis lavage）.After successful modeling,blood was collected from the eyeball,and the mice were sacrificed by dislocation.3.Data collection:（1）Visual observation of mice vaginal appearance and reproductive system anatomy;（2）The vaginal secretion smears of mice and clinical groups were observed under microscope;（3）The results of rapid detection of sialidase,ammonia test and p H value in the clinical group and each mice group were compared;（4）The levels of IL-6 and IL-10 in mice serum were detected by ELISA;（5）HE staining and histopathological score of mice cervicovaginal tissue were observed under microscope.【Results】1.Vaginal Appearance and Reproductive Inflammation: In Group F,the vaginal appearance and reproductive system of mice showed local tissue edema,and the vagina contained mucous or bloody secretions.The degree of inflammation,redness and swelling was generally lighter than that in Groups C to E.2.Vaginal Discharge Smear: In Groups C to F,with the extension of the experiment time and under the microscope,the vaginal secretion smear examination of mice showed that corresponding bacteria and necrotic cells can be seen,the epithelial cells are arranged disorderly,the edge of the cell membrane is blurred,the exfoliation of epithelial cells increases,and inflammatory cells and increased red blood cells.The vaginal secretion smear in the clinical group showed various bacteria,necrotic cells,clue cells,inflammatory cells and red blood cells,as well as disordered epithelial cells and exfoliated epithelial cells.3.Sialidase Rapid Test,p H measurement,and Ammonia test:（1）Compared with Group F,there were statistical differences in the positive rate of hydrogen peroxide,sialidase,leukocyte ester,and prevalence of BV in Group A and Group B;Compared with the clinical group,the above indicators in Group F had no statistical difference;（2）Compared with Group F,the p H values of Group A and Group B were significantly different;But there was no statistical difference between Group F and clinical group;With the prolongation of the experimental time,the increase of times of bacterial perfusion and the aggravation of inflammation in Groups C to F,the p H value rose to varying degrees;（3）Compared with Group F,the positive rate of ammonia test in Group A and Group B were statistically different;But there was no statistical difference between Group F and clinical group;4.Cytokine:（1）Compared with Group F,the levels of IL-6 in Group D and Group E were significantly different;The levels of IL-10 in Group F were significantly different from those in Group E;Compared with Group F,there was no statistical difference in the levels of IL-6 and IL-10 in Groups A to C;（2）There was a significant linear correlation between the levels of IL-6 and IL-10 detected in the serum of mice in each group;（3）The specificity of IL-6 was 85%,the sensitivity was 100%,and the best critical value of 23.596 pg/m L;The sensitivity and specificity of IL-10 were both 100%,and the best critical value of 29.558 pg/m L;The BV diagnostic efficacy of combined detection of IL-6 and IL-10 was higher than that of IL-6 alone,and was the same as that of IL-10 alone.5.HE Staining: HE staining in Group F showed tissue edema,less obvious infiltration of inflammatory cells,and obvious infiltration of lymphocytes.The degree of lesions in Group F was lighter than that in Groups C to E.【Conclusion】1.It was verified that the GV group complied with the preparation standard of BV animal model from the aspects of vaginal appearance,anatomical and pathological indexes,biochemical indexes and immune indexes.2.The mice GV model constructed by Gardnerella vaginalis has a lower degree of inflammation,and similar biochemical indicators to the clinic.It is in line with the characteristics of BV without mucosal inflammation and immunosuppression.3.GV can be used to make a mice model of Bacterial vaginosis in the study of complications,clinical diagnosis,treatment and etc.