CpG基元在细菌DNA诱导小白鼠THP-1释放细胞因子中的作用

Roles of CpG motifs in the release of cytokines induced by bacterial DNA in rats

目的 探讨CpG基元在细菌DNA诱导的细胞因子释放中的作用。方法 实验前 1h经腹腔注射 60 0mg/kgD 氨基半乳糖 (D Galactoamine ,D GalN)敏化小鼠 ,采用纯化的大肠杆菌DNA(EscherichiacoliDNA ,ECDNA)、小牛胸腺DNA(CalfthymusDNA ,CTDNA)、含有CpG基元的硫代寡核苷酸 (CpG oligodeoxynucleotides ,CpGODN )和C与G序列颠倒的硫代寡核苷酸 (Non CpGODN )静脉给予小鼠 ,DNA的注射剂量为 3 0mg/kg ,ODN的剂量为 10nmol/只 ,观察ECDNA、DNA、CpGODN与CTDNA、NON CpGODN导致小鼠死亡情况的差异。体外培养THP 1细胞系 ,在THP 1细胞培养体系中加入上述制剂后 ,测定细胞因子TNF α、IL 6、IL 1β的释放情况 ,观察上述制剂诱导细胞因子释放能力的不同。 结果 ECDNA、CpGODN可诱导小鼠的死亡以及细胞因子的大量释放 ,而CTDNA、NON CpGODN则无此能力。结论 含有CpG基元的寡核苷酸具有诱导巨噬细胞大量释放细胞因子的作用 ,CpG基元在细菌DNA诱导的细胞因子释放中具有重要的作用 。

Objective To investigate the roles of CpG motifs in the release of cytokines induced by bacterial DNA. Methods Mice were sensitized with injection of D GalN (600 mg/kg) into the abdominal cavity 1 h before experiment. Mortality was observed after purified Escherichia coli DNA(EC DNA), calf thymus DNA(CT DNA), phosphorothioate backbone CpG oligodeoxy nucleotides (CpG ODN) and CG sequence inverted oligodeoxy nucleotides (non CpG ODN) were injected venously into mice. The injection dosage of DNA given was 30 mg/kg but ODN was 10 nmol/mouse. THP 1 cell lines were cultured in vitro . After the above reagents were added into the culture, TNF α, IL 6, IL 1β levels were detected to observe the different abilities of these reagents to induce the release of cytokines. Results EC DNA and CpG ODN could induce the death of mice and the large amount of release of cytokines, but CT DNA and Non CpG ODN could not. Conclusion CpG ODN has the ability to induce macrophage to release cytokines largely. CpG motifs, which may play an important role in the release of cytokines induced by bacterial DNA, may probably be the structural basis of bacterial DNA.