The Immune Effect Of CpG ODN Adjuvant On Rabies Vaccine

Objective Rabies is caused by rabies virus,the mortality rate of patients is 100%.Rabies vaccination is still the main protective measure.Purified Vero cell rabies vaccine(PVRV)is currently the mainstream vaccine.Human diploid cell rabies vaccine(HDCV)is recognized as a highly safe rabies vaccine.But the price of HDCV is very expensive due to the lack of extensive industrialization,so the cost of HDCV in many developing countries cannot afford.In addition,rabies passive immune agents lack of supply,and post exposure vaccination programs mostly shot four or five;immunity effect of Rabies vaccine for animals on dogs was not optimal,and neutralizing antibody titers in 27% of the immunized dogs were insufficient to defense the infection.In view of this,shorten the programs and reduce the amount of each antigen immune injection is the main direction of vaccine development.To find a way to enhance the immune effect of rabies vaccine adjuvants for vaccines used for humans and animalshave the potential commercial value.Methods Cp G oligodeoxynucleotides(Cp G ODN)is a synthesized nucleotide sequence containing unmethylated cytosine and guanine,and is a kind of immune adjuvant that has good effect.This study used the rapid fluorescent focus inhibition test(RFFIT)to detect rabies virus neutralizing antibody(RVNA)in mice injected with different doses of Cp G ODN.The detection of cytokines in spleen cells of mice was detected by enzyme-linked immunosorbent assay(ELISPOT)and real time quantitative PCR method.To evaluate the safety of different doses of Cp G ODN adjuvants from the morphological changes of spleen and pathological changes after hematoxylin and eosin stain in mice.The above experimental study was performed to determine the optimal dose of Cp G ODN in mice.The optimization of the optimal dose of Cp G ODN combined with a commercially available rabies vaccine antigen and immune procedure: RV group,(RV+Cp G ODN)(1/2RV+Cp G ODN),(1/4RV+Cp G ODN),(1/8RV+Cp G ODN)group,Essen.Balb/C mice were immunized on day thirty-fifth after the first immunization of blood RFFIT detection of RVNA serum titer of centrifugal separation.Optimization of experimental rabies vaccination program for Cp G ODN City: two needle,three needle,four needle,five needle immune procedure,divided into two groups containing adjuvant two needles(0,3 days),three needles(0,3,7days),four(0,3,7,14 days),five needle group(0,3,7,14,28 days)acupuncture group and without adjuvant five needle group(0,3,7,14,28 days),the diluted vaccine was 5 ?g / Cp G ODN as adjuvant,immune Balb/C mice,blood samples were collected thirty-fifth days after the first immunization.Neutralization of RVNA was detected using RFFIT.Study on the protective effect of the vaccine is exposed to rabies after sale of Cp G ODN combined with CVS-11,Balb/c in mice after infection with Cp G,ODN combined with different amount of rabies vaccine(RV,1/2RV,1/4RV,1/8RV)immune program ESSEN injection,to evaluate the protective effect of mice after exposure to Balb/c.Results the positive rate of ODN antibody and positive turn time of Cp G and rabies vaccine group were higher than that of control group in mice.Thirty-fifth days after the first immunization,the titer of neutralizing antibody in low and middle dose group increased by 5-6 times and 3-4 times,respectively.Cp G ODN adjuvant can significantly enhance the Th1 type immune response of rabies vaccine,and promote the secretion of IFN-? in mouse spleen cells,while the cytokine IL-4 secretion of Th2 immune response has no obvious change.the difference was statistically significant.The high dose group of mice spleen enlargement,the white pulp in the periarterial lymphatic sheath thickening,tingible body macrophages increased number of paracortical tingible body macrophages increased in number,while the low and middle dose group of mice spleen enlargement,the white pulp in the periarterial lymphatic sheath normal spleen white pulp.The neutralizing antibody titer of the(1/4 RV+Cp G ODN)group was slightly higher than that of the non adjuvant rabies vaccine group(1/2RV+Cp G ODN).Cp G ODN combined with rabies vaccine immunization program 4 mice immunized mice produced the highest neutralizing antibody titer.The survival rate of RV+Cp G rabies vaccine group was 50% higher than that of the control group without adjuvant vaccine,the difference was statistically significant.Conclusions Cp G ODN can have a significant effect on the immune efficiency of rabies vaccine in mice and can enhance the immune effect of rabies vaccine to protect mice after exposure.So,Cp G ODN is a kind of potential rabies vaccine adjuvant.