IL-12缺失雌鼠经泌尿生殖道衣原体上行感染致肾脏病变观察

Intravaginal infection with Chlamydia muridarumcan cause renal lesions as a result of the infection ascending through the genitourinary tract in the absence of IL-12

目的了解在Il-12缺失小鼠中衣原体经外生殖道进入肾脏导致肾脏病变情况。方法试验用野生型(wildtype,wt)、IL-12p35KO及IL-12p40KO小鼠,每组10只,经阴道分别接种1×104 IFUs鼠衣原体(MoPn),于感染后第45、87和100d处死小鼠。分离其肾脏、尿道、膀胱、肺、肝、脾、心脏组织,分别加入预冷的SPG,经组织匀浆器匀浆、超声破碎后做倍比稀释。取稀释液感染Hela细胞,培养24h后进行间接免疫荧光试验,计数各组织中衣原体包涵体数量。其余5只小鼠的组织进行HE染色,检测其病理变化。结果感染后第45、87和100d,3种小鼠肝、肺、心脏和脾脏组织中均未检出活的衣原体;而在肾脏、尿道、膀胱组织中除wt小鼠未检出活的衣原体外,IL-12p35KO和IL-12p40KO小鼠均检出衣原体。其中,感染后45d,IL-12p35KO和IL-12p40KO小鼠的肾脏、尿道、膀胱组织中检出的衣原体数量分别为4.12×104、4.30×104、2.88×104和4.54×105、3.48×105、1.21×105;且在87和100d,IL-12p40KO小鼠3种组织的衣原体检出数量为6.92×103、3.0×103、105和2.16×104、30、23,显著高于IL-12p35KO小鼠的35、20、13和32、12、2。对各组小鼠肾脏、尿道、膀胱组织进行病理检测,盲法判断组织病变程度,wt小鼠肾脏几乎无明显病变,IL-12p35KO和IL-12p40KO小鼠肾脏均发生严重积水和脓肿,且各组小鼠膀胱、尿道组织病变程度与肾脏病变程度成正相关。结论雌性小鼠在IL-12缺失情况下,衣原体经生殖道感染后可经泌尿生殖道组织上行感染导致肾脏病变。

Objective To explore the manner in which intravaginal infection with Chlamydia muridarumcauses renal lesions in the absence of Il-12. Methods C57 BL/6 Jwild-type(wt)and mice deficient in IL-12 p35(IL-12 p35 KO)and IL-12 p40(IL-12 p40 KO)were intravaginally inoculated with 1 × 104 IFUs of live C.muridarum.Ten mice in each group were sacrificed on day 45,87,and 100 after infection.Kidney,urinary tract,bladder,lung,liver,spleen,and heart tissues were isolated and added to pre-cooled SPG,homogenized using a tissue homogenizer,sonicated,diluted,and used to infect HeLa cells.After 24 hours of culturing,an indirect immunofluorescence assay was performed to count the number of Chlamydiainclusion bodies in each type of tissue.The tissues of the other 5 mice were subjected to H&E staining for pathological examination. Results On day 45,87,and 100,live Chlamydia was not detected in the lung,liver,spleen,or heart tissues in wt,IL-12 p35 KO,or IL-12 p40 KO mice.Chlamydia was not detected in the kidney,urinary tract,or bladder tissue of wt mice,but high numbers were detected in IL-12 p35 KO and IL-12 p40 KO mice.On day45,4.12×104 Chlamydia were found in kidney tissue,4.30×104 were found in urethra tissue,and 2.88×104 were found in bladder tissue from IL-12 p35 KO mice.Similarly,4.54×105 Chlamydia were found in kidney tissue,3.48×105 were found in urethra tissue,and 1.21×105 were found in bladder tissue from IL-12 p40 KO mice.On day 87,6.92 ×103,3.0 × 103,and 105 Chlamydia were detected in IL-12 p40 KO mice;on day 100,2.16 × 104,30,and 23 Chlamydia were detected.These numbers were significantly higher than those in IL-12 p35 KO mice,which were 35,20,and 13 on day 87 and 32,12,and 2 on day 100.The kidney,urethra,and bladder tissues of each group mice were examined pathologically,and the extent of pathological changes in each tissue was blindly determined.There were few obvious lesions in the kidneys of wt mice,but severe hydronephrosis and abscesses were evident in the kidneys of IL-12 p35 KO and IL-12 p40 KO mice.Lesions of the bladder and urethra were observed in each group.The extent of those lesions correlated with the extent of renal lesions. Conclusion In the absence of IL-12,intravaginal infection with C.muridarum can cause renal lesions when the infection ascends through the genitourinary tract.