双歧杆菌DNA对小鼠腹腔巨噬细胞的激活效应

Active effect of bifidobacteria DNA on peritoneal elicited macrophages of mice

目的 探讨双歧杆菌DNA对小鼠腹腔巨噬细胞的激活作用 ,为微生物DNA制剂开发应用于临床提供科学依据。方法 纯化提取双歧杆菌基因组DNA ,并鉴定DNA制品CpG基序甲基化程度。收集双歧杆菌DNA( 10 μg/ml)体外诱导培养 2 4h的小鼠腹腔巨噬细胞培养上清 ,采用ELISA法检测培养上清中TNF α、IL 12的含量 ,用Griess试剂检测其NO的含量 ;FACS检测巨噬细胞的吞噬功能。结果 实验组 (双歧杆菌DNA组 )巨噬细胞产生TNF α、IL 12及NO的水平分别为 12 0 .12± 13 .2 1pg/ml、4 0 5 .5 1± 5 1.80 pg/ml和 11.12± 1.0 1μmol/L ,巨噬细胞吞噬功能的平均荧光强度为 2 8.12± 3 .5 8;对照组 (PBS组 )分别为 5 .82± 1.5 4 pg/ml、10 .17± 1.2 7pg/ml、2 .14± 0 .2 8μmol/L和 9.3 2± 1.0 1,两组间各项指标比较均有显著性差异 (均P <0 .0 1)。结论 双歧杆菌DNA能激活巨噬细胞 ,可增强巨噬细胞TNF α、IL 12及NO产生的水平及吞噬功能。

Objective: To explore the active effect of bifidobacteria DNA on peritoneal elicited macrophages of mice(PEMφ). Methods: The DNA of bifidobacteria was purified, and the degree of unmethylated CG dinucleotides (CpG motifs) was tested. The culture supernatant of PEMφ, which had been exposed to bifidobacteria DNA(10(g/ml) for 24 hours, was collected and then TNF αand IL 12 were detected by ELISA method and the content of nitric oxide(NO)was determined by Griess reagent. The phagocytosis of the PEMφ was detected by FACS. Results: In the experimental group, the levels of TNF α, IL 12, NO and the phagocytosis of the PEMφ (bifidobacteria DNA group) were respectively 120.12±13.21 pg/ml,405.51±51.80 pg/ml,11.12±1.01 μmol/L and 28.12±3.58 Geo Mean, while those in the control group (PBS group) were 5.82±1.54pg/ml,10.17±1.27 pg/ml, 2.14±0.28 μmol /L and 9.32±1.01 Geo Mean. The differences were significantly obvious (P<0.01). Conclusion: Bifidobacteria DNA can activate PEMφ to secrete more TNF α,IL 12 and NO, and also enhance its phagocytosis significantly.