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.