The E protein of dengue virus type Ⅱ was presented on ferritin of Helicobacter pylori to construct a novel dengue nanoparticle vaccine candidate,and the immunological indexes of the vac-cine were evaluated,aiming to provide new ideas for the development of dengue vaccine.The re-combinant plasmid of E-Ferritin was optimized and synthesized,and then transfected into HEK-293F cells.The recombinant protein was expressed,identified,purified and analyzed.Mice were im-munized with E-Ferritin nanoparticle vaccine by intramuscular injection on the hind limbs on the day 0,14 and 28.ELISA,neutralization test,flow cytometry and lymphocyte proliferation test were used to detect the levels of specific antibodies,neutralizing antibodies,CD3+,CD4+and CD8+T lymphocytes in spleen cells and the proliferation of spleen lymphocytes after specific stimulation.The target protein with a size of about 69 kDa was expressed in the cells with a single band.The purified protein concentration was 0.407 g/L,and the purity was 82.32％.The results from transmission electron microscopy showed that E-Ferritin protein could be recombined into a particle structure with a particle size of about 50 nm.The results of mouse immune experiments showed that E-Ferritin protein had good immunogenicity.The average specific antibody titer of E-ferritin protein in serum was 1∶92 160 after immunization 42 d.The main subclass of antibody was IgGl.The results of flow cytometry showed that E-Ferritin as an immunogen could induce higher levels of CD4+and CD8+T lymphocyte immune response.In lymphocyte proliferation test,the level of specific stimulation in the vaccine group was significantly higher than that in the non-specific stimulation group.In conclusion,the dengue virus envelope protein ferritin nanoparticle vaccine constructed in this study has good immunogenicity,which can provide reference for the de-velopment of new dengue vaccine candidates.

The SYBR Green Ⅰ real-time fluorescence quantitative PCR detection method was used to determine the prevalence of Japanese encephalitis virus(JEV)in mosquito vectors and cattle se-rum samples in Xinjiang.The E gene fragment of the JEV strain was amplified by PCR,cloned into a pEASY-Blunt vector,produced as a recombinant plasmid,and its sensitivity,specificity and re-producibility were verified.Between 2021 and 2022,serum samples were taken in the regions of Hami,Altay,Ili,Aksu,and Kashi in order to monitor the prevalence of JEV in livestock in Xin-jiang.The positive rate was discovered and evaluated using the established detection method.The established detection method showed a good linear relationship,and the detection interval was 4.03X102-4.03×109 copies/pL.The correlation coefficient was 0.995,the slope was-3.431,and the extreme value of the lower limit of sensitivity was 4.03 × 102 copies/pL.This method has no specific amplification for Zika virus(ZIKV)and Dengue virus(DENV).The intra group coefficient of variation of reproducibility was 0.53％-1.27％,and the inter group coefficient of variation was 0.48％-1.43％.Using this method to detect serum samples from livestock in Xinjiang from 2021 to 2022,the total positive rate was 3.28％,with positive detection rates in horses,cows,and sheep being 2.35％,6.77％,and 3.74％respectively,the virus was identified as Type Ⅰ JEV.A SYBR Green Ⅰ real-time PCR method for the detection of genotype 1 JEV was established.JEV was de-tected in the serum of horses,cattle and sheep in Xinjiang,with a total positive rate of 3.11％.