牛源致病性Escherichia coli O8对小鼠小肠结构及免疫相关细胞的影响

为研究小鼠感染牛源致病性大肠杆菌(Escherichia coli)O8后小肠结构和免疫相关细胞的变化,用试验观察小鼠感染后的患病症状,采集小鼠小肠组织样品,HE和PAS染色后观察其病理切片,测定小肠结构中肠绒毛长度、隐窝深度、肠绒毛长度/隐窝深度(V/C)值、肌层厚度及免疫相关细胞肠上皮淋巴细胞和杯状细胞的数量。结果表明,小鼠感染牛源致病性E.coli O88~12h出现患病症状;24h出现明显患病症状,个别小鼠死亡;36~48h小鼠患病症状更加严重,死亡小鼠增多;72h不再出现死亡小鼠,未死亡小鼠精神状态和行动能力全面好转。小鼠感染牛源致病性E.coli O8后,小肠肠绒毛长度、V/C值、肌层厚度、肠上皮淋巴细胞和杯状细胞数量先减少后增多,隐窝深度先增大后减小。小鼠感染牛源致病性E.coli O8后0~72h小肠各指标出现规律性变化,其中,36h小鼠感染最严重,72h开始恢复。

Effect of pathogenic Escherichia coli O8 from cow feces on the small intestinal structure and immunity-associated cells of mice

The study was conducted to investigate the effect of pathogenic Escherichia coli O₈ form cow feces on the small intestinal structure and immunity-associated cells of mice.Clinical symptoms of mice challenged with pathogenic E.coli O₈ were observed by animal experiment.Small intestinal samples were collected and the pathological sections were observed by HE and PAS staining.Length of villus (V),depth of crypt (C),V/C value,thickness of muscularis,and the number of intraepithelial lymphocyte (IEL) and goblet cell (GC) were detected.The results showed that mice appeared clinical symptoms 8-12 h after challenged with E.coli O₈.Mice appeared obvious clinical symptoms 24 h after challenged with E.Coli O₈,and some mice died.Mice appeared more serious clinical symptoms 36-48 h after challenged with E.coli O₈,and more mice died.Mice recovered 72 h after challenged with E.coli O₈,and no more mice died.The length of villus,V/C value,the thickness of muscularis,and the numbers of IEL and GC were decreased at the beginning and then increased.However,the depth of crypt was increased at the beginning and then decreased.Small intestinal indexes of mice appeared regular changes 0-72 h after challenged with E.coli O₈,the most serious infection time of mice was 36 h,and they recovered gradually after 72 h.