重组人乳铁蛋白对小鼠沙门菌感染抑制效果

目的研究转基因水稻来源的重组人乳铁蛋白(rhLF)在小鼠体内抑制沙门菌感染的效果。方法选择Balb/c小鼠建立沙门菌感染模型; 将Balb/c小鼠按体重随机分为2组,即沙门菌对照组和rhLF干预组,每组12只;染菌前2h,rhLF干预组小鼠经口灌胃20 mg/mL rhLF 0.3 mL,对照组小鼠经口灌胃0.3 mL PBS;之后每天灌胃相同量的rhLF(6 mg/d)或PBS;每天观察小鼠一般情况;7 d后,心脏穿刺取小鼠血液观察菌血症,取肝脏和脾脏组织进行细菌计数分析,取肝脏、脾脏、肾脏和小肠进行病理观察。结果各组小鼠体重变化、生存情况在组间无明显差异(P>0.05);2组小鼠的肝脏重和肝体比值、脾脏重和脾体比值相似(P>0.05);rhLF干预组小鼠的血液、肝脏和脾脏的染菌率和染菌量与对照组相比,呈现降低趋势,但差异无统计学意义(P>0.05);病理分析显示rhLF干预组小鼠的炎症程度有减轻,但差异无统计学意义(P>0.05)。结论6 mg/d的rhLF不能明显减轻小鼠沙门菌感染的炎症程度。

Effect of recombinant human lactoferrin from transgenic rice on Salmonella enterica serovar Typhimurium infection in mice

ObjectiveTo study the effect of recombinant human lactoferrin(rhLF)from transgenic rice on Salmonella enterica serovar Typhimurium(ST)infection in mice.MethodsBalb/c mice was used to build ST infection model.According to body weight,the Balb/c mice were divided randomly into two groups:a ST infection group as control and a rhLF intervention group(12 mice in each group).Two hours before the infection with 0.3 mL of 1×10⁶ colony-forming unit(CFU)of ST,12 mice received 0.3 mL rhLF of 20 mg/mL and 12 received phosphate-buffered saline(PBS)by gavage.After the infection,the mice received rhLF(6 mg/day)or PBS by the same route,respectively,for 7 days.General behavior of the mice was observed daily.Seven days after the infection,blood samples of the mice were obtained through heart punctutre for determination of bacteriaemia.Liver and spleen of the mice were obtained for analysis of bacterial count and liver,spleen,kidney,and intestine tissues of the mice were obtained for pathology observation.ResultsThere was no significant differences in the body weight and survival between the control and rhLF groups(P>0.05).The wet liver weight and the ratio of liver to body weight,wet spleen weight,and the ratio of spleen to body weight were similar between two groups(P>0.05).Compared to the control,the infection rate and the bacteria quantity of blood,liver and spleen of the mice in rhLF group were lower than those of the control group; however,there were no statistical differences(all P>0.05).Pathological analysis showed that the inflammation of the mice in the rhLF group was alleviated,but no statistical differences existed(all P>0.05).ConclusionrhLF at concentration of 6 mg/day could not significantly reduce the degree of inflammation induced by ST infection in mice.