卡介菌基因组 DNA和卡介菌多糖核酸免疫调控活性的比较(英文)

Comparative immunoregulatory property analysis of genomic DNA and polysaccharide nucleic acid fraction from Mycobacterium bovis Bacillus Calmette-Guérin

目的 :比较研究卡介菌 (Mycobacterium bovis Bacillus Calm ette- Guérin,BCG)基因组 DNA(BCG- DNA)和卡介菌多糖核酸 (BCG- PSN)的免疫调控活性。 方法 :制备高纯度的 BCG- DNA,小鼠脾细胞 (splenocyte)和人外周血单个核细胞 (pe-ripheral blood m ononuclear cell,PBMC)分别与 BCG- DNA和 BCG- PSN共同培养 72 h,采用 EL ISA方法检测细胞培养上清中 IFN -γ的水平。结果 :所制备的 BCG- DNA纯度较高 ,DNA含量达 95 .3%。琼脂糖电泳显示 :BCG- DNA片断大小集中于2 0 0～ 2 5 0 bp。EL ISA结果表明 BCG- DNA与 BCG- PSN均可显著激活小鼠脾细胞和人外周血单个核细胞 ,有效诱导 IFN-γ的产生 (P<0 .0 1 )。当浓度达 1 0μg/ m l以上时 ,BCG- DNA免疫调控作用优于 BCG- PSN(P<0 .0 1 )。 结论 :BCG- DNA可显著诱导 Th1型细胞因子 IFN-γ的产生 。

Objective:To compare the immunomodulatory property of ge nomic DNA from Mycobacterium bovis Bacillus Calmette Guérin (BCG DNA) and polysaccharide nucleic acid fraction from Mycobacterium bovis Bacil lus Ca lmette Guérin (BCG PSN).Methods:Highly purified BCG DNA was isolated.Murine splenocyte or human peripheral blood mononuclear cell (hPBMC) were incubated with BCG DNA or BCG PSN. IFN γ in cell cultures was tested b y ELISA.Results:BCG DNA was extracted; the concentrat ion of DNA was 95.3%. Agarose electrophoresis showed that the size of BCG DNA is 200 250 bp.ELISA test showed that both BCG DNA and BCG PSN could ac tivate murine splenocytes and hPBMC,and significantly increase IFN γ level ( P <0.01).Moreover,BCG DNA induced higher levels of IFN γ compared to BCG PS N when the concentration≥10 μg/ml ( P <0.01),and such effect was dose de pendent.Conclusion:Compared with BCG PSN,BCG DNA can signi fi cantly induce typical Th1 cytokine(IFN γ) in vitro , and it is a poten t Th1 immunoregulator.