干酪乳酸杆菌对新生大鼠Toll样受体2和甘露醇受体影响及其免疫调节作用的可能机制的探讨

The effect of probiotic lactobacillus casei to TLR2 and CD206 of the newborn SD mice and the mechanisms by which probiotic bacteria affect the immune system

目的通过观察干酪乳酸杆菌对新生鼠Toll样受体2(TLR2)和甘露醇受体(CD206)的影响,探讨其免疫调节作用的可能机制。方法64只新生SD大鼠随机分为对照组(32只)、干预组(32只),各组再以第1、2、3、4周为时间点分为4个亚组,干预组每天给予干酪乳酸杆菌活菌悬液(1×109CFU/只)治疗,共4周,每周取小肠进行TLR2及CD206免疫荧光染色,高倍镜下计数阳性细胞数,并进行统计分析。结果(1)TLR2和CD206阳性细胞随日龄增加而增加;(2)干预组TLR2和CD206阳性细胞数明显高于对照组(P<0.05)。结论新生鼠肠道中TLR2和CD206受体随周龄增加而增加,干酪乳酸杆菌能够激活肠道中TLR2及CD206细胞。

Objective To investigate the immune regulatory mechanism of probiotic lactobacillus casei by observing its effects on TLR2 and CD206 of newborn rats.Methods Sixty-four newborn SD rats were randomly divided into controlled group（n=32）and intervened group（n=32）,each of which were then separated into four groups according to the drug given time that was used in 1,2,3 and 4 weeks respectively.Probiotics（1×10^8·kg^-1·d^-1）was given to intervention group everyday for 4 weeks totally.First week,the small intestine of the first group was collected to determine the CD206 and TLR2 through immunofluorescence staining,and to count the positive cells under high-power microscope,and the same methods with the rest three groups.Results（1）The positive cells of CD206 and TLR2 from small intestine increased by day.（2）The positive cells of CD206 and TLR2 from intervention group were obviously higher than that of controlled group.Conclusion The receptors of CD206 and TLR2 from the small intestine of newborn rats increased by week,and Lactobacillus casei can activate CD206 and TLR2,which can then increase the mucosal immune response.