Roles of CpG motifs in the release of cytokines induced by bacterial DNA in rats / 第三军医大学学报

ABSTRACT

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 ?, IL 6, IL 1? 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.