中文摘要：

目的 研究使用乳凝集素（Lactadherin）对SD新生大鼠感染轮状病毒（RV）腹泻的病情及肠道分泌细胞因子IL-6、TNF-α、IFN-γ的影响,探讨乳凝集素对新生大鼠感染RV的预防和治疗作用.方法 将100只7日龄SD新生大鼠随机分为4组,人工喂养至10日龄.给10日龄的新生大鼠喂服RV培养液作为RV感染组,RV感染前和后喂服0.25 mg/只的乳凝集素作为乳凝集素预防组和乳凝集素治疗组,正常对照组喂服同剂量不含病毒的细胞培养液.分别于感染病毒后不同时间点观察大鼠临床症状及腹泻情况,酶联免疫吸附法检测肠内容物上清细胞因子IL-6、TNF-α、IFN-γ的浓度变化.结果 对照组新生大鼠未出现腹泻,其余三组在感染病毒后1 d相继出现腹泻,病毒感染组大鼠在感染病毒后第3天腹泻最严重,感染后第7天腹泻症状结束.乳凝集素治疗组和乳凝集素预防组大鼠腹泻程度轻于病毒感染组,病程较病毒感染组缩短.病毒感染组新生大鼠体重在感染后第3天起和对照组相比有差异（P〈0.05）,而乳凝集素预防组和乳凝集素治疗组与对照组相比无差异.病毒感染组肠道IL-6、TNF-α浓度在病毒感染后第3天达高峰,之后呈降低趋势.病毒感染组IFN-γ浓度在感染后第5天达高峰.乳凝集素预防组和乳凝集素治疗组的IL-6、TNF-α浓度水平显著低于病毒感染组（P〈0.05）,且IFN-γ在病毒感染后第3天达高峰.结论 乳凝集素能够改善RV感染新生大鼠腹泻严重程度、缩短腹泻病程,降低肠道内IL-6、TNF-α浓度及提高IFN-γ的浓度,提示乳凝集素对新生大鼠RV感染有预防和治疗作用.

英文摘要：

Objective To study the influences of Lactadherin on the diarrhea disease and the intestinal cytokines IL-6, TNF-αγ, IFN-γ of newborn rats infected with rotavirus and to explore the potential effects of Lactadherin in the prevention and treatment of rotavirus infection. Methods One-hundred seven-day-old SD rats, artificial feeding to 10 days,were randomly divided into four groups, rotavirus infection group, lactadherin pretreated and rotavirus infection group, rotavirus infection and lactadherin treated group, and the control group. The clinical manifestation of newborn rats were observed at different time points. The levels of IL-6, TNF-α and IFN-γ in the intestinal content supernatant were detected by ELISA. Results Rats of control group didn＇t appear diarrhea,while other groups developed diarrhea by 24 hours. Rats of rotavirus infection group developed the most severe diarrhea on the post-infection day 3, and ended on the post-infection day 7. Lactadherin pretreated rats and lactadherin treated rats had milder diarrhea and shorter duration than those of the retavirus infection group. The weight of rotavirus infected rats had the difference compared with the control group from the post-infection day 3, which were not observed in lactadherin pretreated group and lactadherin treated group. The level of IL-6 and TNF-α in the intestinal contents of rotavirus infection group reached a peak on the post-infection day 3, while IFN-γ on post-infection day 5. The levels of IL-6 and TNF-α in lactadherin pretreated group and lactadherin treated group were significantly lower than those in rotavirus infection group. The concentration of IFN-γ in lactadherin pretreated group and lactadherin treated group reached a peak on the post-infection day 3. Conclusions Lactadherin improves the severity of rotavirus diarrhea in newborn rats, down-regulate the levels of IL-6 and TNF-α and boost the level of IFN-γ in intestinal tract after infection. It may play a certain role on the prevention and treatment of newborn rats w