解脲脲原体血清型1和3感染BALB／c雌性小鼠生殖道的致病性比较

Comparison of pathogenicity between Ureaplasma urealyticum serotype 1 and 3 in genital tract of female BALB/c mice

目的探讨相同浓度解脲脲原体血清型1（Uul）和3（Uu3）及混合感染（Uul和Uu3）在BALB／c雌性小鼠模型生殖道的致病性。方法156只雌激素预处理过的BALB／c小鼠随机分为4组，Uul组、Uu3组、Uul＋Uu3组每组48只，无菌培养液对照组12只，分别阴道接种相同浓度（10^6拷贝／g）Uu。接种后第1、3、7、14、21、35天随机处死每实验组各8只及对照组2只小鼠。取宫颈、子宫内膜及输卵管行HE染色，光镜观察；取接种后第14天宫颈管黏膜扫描电镜观察。数据采用卡方检验进行统计学分析。结果接种相同浓度不同血清型Uu后3～35d，Uul组、Uu3组、Uul＋Uu3组的总致病率分别为35．0％（14／40）、47．5％（19／40）、62．5％（25／40），3组致病率差异有统计学意义（P〈0．05）。对照组无致病。结论BALB／c小鼠生殖道接种相同浓度的Uul、Uu3、Uul＋Uu3后，Uul＋Uu3组致病性最强，Uul组最弱。

Objective To investigate the pathogenicity of the same concentration of Ureaplasma urealyticum serotypel （Uul） and 3 （Uu3）, alone or in combination, in genital tract of female BALB/c mice. Methods A total of 144 estradiol-pretreated adult female BALB/c mice were randomly and equally divided into 3 groups to be inoculated intravaginally with the same concentration （106 copies/g） of Uul and Uu3 alone or in combination. Twelve estradiol-pretreated female BALB/c mice were inoculated with sterile culture solution and served as the control group. At 1, 3, 7, 14, 21, 35 days after the inoculation, 8 mice in each Uu-inoculated group and 2 mice in the control group were sacrificed. Tissue specimens were obtained from the cervix, endometria and fallopian tube and subjected to hematoxylin-eosin staining followed by light microscopy. Scanning electron microscopy was used to observe the tissue specimens collected at 14 days from cervical mucosa of mice infected by Uu. Chi-square test was performed for statistical evaluation. Results The total infection rate of Uu within 3-35 days after the inoculation was 35.0% （14/40）, 47.5% （19/40） and 62.5% （25/40） in the Uul group, Uu3 group, and combination group respectively （X^2 = 6.07, P 〈 0.05）. None of these mice was infected by Uu in the control group. Conclusions At the same inoculation concentration, the combination of Uul and Uu3 shows the strongest pathogenicity in genital tract of BALB/c mice, followed sequentially by Uu3 and Uul alone.