DNA vaccine provides a promising method for preventing and treating diseases. However, the low immunogenicity restricts its application. New approaches are urgent to be explored to enhance the immune response of DNA vaccine. MicroRNAs are endogenous, small non-coding RNAs which play parts in gene expression inhibition. In this study, microRNA-9 (miR-9) was found to inhibit the expression of the GLU-A-P antigen protein encoded by the anti-caries DNA vaccine. Mutation of miR-9 binding sites in the gene fragment encoding GLU-A-P antigen protein significantly increased the expression of antigen protein. Moreover, miR-9 sponge can improve the expression of the GLU-A-P antigen protein. The co-immunization with miR-9 sponge and anti-caries DNA vaccine significantly enhanced the specific immune response in vivo. In conclusion, attenuating the inhibition of endogenous miR-9 enhanced the antigen expression and immunogenicity of the anti-caries DNA vaccine.

中文翻译：

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通过减弱内源性miR-9的抑制作用来增强抗变形链球菌DNA疫苗的免疫原性。

DNA疫苗为预防和治疗疾病提供了一种有前途的方法。但是，低免疫原性限制了其应用。迫切需要探索新的方法来增强DNA疫苗的免疫反应。微小RNA是内源的，小的非编码RNA，其在基因表达抑制中起作用。在这项研究中，发现microRNA-9（miR-9）可以抑制抗龋齿DNA疫苗编码的GLU-AP抗原蛋白的表达。编码GLU-AP抗原蛋白的基因片段中miR-9结合位点的突变显着增加了抗原蛋白的表达。此外，miR-9海绵可以改善GLU-AP抗原蛋白的表达。与miR-9海绵和抗龋齿DNA疫苗共同免疫可显着增强体内的特异性免疫反应。结论，