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Objective:To investigate the effects of different chimerism strategies and different immune ways on the two antigen-dominant regions of Xinjiang hemorrhagic fever virus (XHFV) glycoprotein.Methods:The 5' end was added or not added with interleukin-2 (IL-2) signal peptide and the general-purpose auxiliary T cell epitopes as different design strategies. GcⅠ and GcⅡ and the epitopes previously identified on GcⅠ (Gc 233-248, Gc 241-256 and Gc 281-296) were fused and constructed into the eukaryotic expression vector pVAX1 and the prokaryotic expression vector pET-28a. The recombinant prokaryotic plasmid transformed into E.coli BL21 was induced and purified, and the recombinant eukaryotes were extracted by indirect immunofluorescent assay. BALB/c mice were immunized by protein immunity, gene immunity, and DNA prime-protein boost immunity. The IgG antibody level was measured by ELISA. The immune effect was evaluated by the proliferation of T-lymphocytes and the content of cytokines in the spleen. Results:The results of double enzyme digestion and sequencing showed that eight recombinant plasmids were successfully constructed, and the recombinant eukaryotes were successfully expressed in vitro by fluorescence microscopy. After three times of immunization, the IgG level and the proliferation of T-lymphocytes in the spleen of mice in the experimental group were significantly higher than those in the control group ( P<0.01). The mass concentration test results of Th2 cytokines IL-4 and Th1 cytokines interferon-gamma (IFN-γ) revealed that the response of the DNA prime-protein boost immunity was biased to Th1. Conclusions:The multi-epitope chimeric vaccine of XHFV glycoprotein was successfully constructed, and the target antigen could be expressed effectively in vivo. The immune groups stimulated stronger humoral and cellular immune responses compared with the control group. Among them, the immune effect of pVAX1-ST(GcⅠe+GcⅡ) combined with recombinant protein r(GcⅠe+GcⅡ) was the best, and it is expected to be a new candidate vaccine for XHFV.
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Abstract@#Globally, non-pharmacological interventions, such as keeping social distance and wearing masks, are the primary prevention and control strategy in the early stage of the coronavirus disease 2019 (COVID-19) pandemic. The successful development and the urgency use of the COVID-19 vaccines in some countries brings a new stage of combining immunization with non-pharmacological interventions in the fight with COVID-19. For the shortage of vaccines, the immunization strategies vary in countries. To end the pandemic, 47%-85% of the population should be immunized with effective COVID-19 vaccines, thus we should boost the yield of vaccines, formulate scientific immunization strategies, promote the mass immunization, improve the willingness of vaccination, and increase the equity of vaccine allocation; meanwhile, we should strengthen the surveillance of virus variation, vaccine effectiveness and safety, and keep on the vaccine research to copy with the potential threat of the virus variation.
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Health care workers have higher risk of influenza infection because of their occupational exposure to infected patients. Infection of the health care workers may not only result in the increasing risk of the nosocomial infection and family transmission, but also disrupt the health services due to absence from work. Health care workers were recommended as a priority group of influenza vaccinationin more than 40 countries and regions in the world. In recent years, domestic surveys show that the influenza vaccine coverage among health care workers was low. This paper outlines the current status and related policies of influenza vaccination among health care workers in China and global. Additionally, we analyzed and discussed the proper immunization strategy of influenza vaccine for medical staff in China.
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In 2016, the World Health Assembly endorsed the Global Health Sector Strategy on viral hepatitis, with aim to eliminate viral hepatitis as a public health threat by 2030, which may reduce the number of new cases of chronic hepatitis B by 90% (0.1% HBsAg prevalence among children) and mortality rate by 65%. In order to achieve this goal, blocking mother-to-child transmission of hepatitis B virus (HBV) is of paramount importance, especially in underdeveloped areas with high prevalence of HBV. In this paper, we discussed the status of chronic HBV infection and its serological and virological characteristics in women of childbearing age in China as well as the optimal dose of immunoglobulin in the combined passive-active immunoprophylaxis in infants born to HBsAg-positive mothers. In addition, the strategies for preventing mother-to-child transmission of HBV in terms of post-immunization testing, increased-dose vaccination (certainty/uncertainty) and follow-up of these infants.
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The aim of this study is to investigate the immune effects of BCG primary immunization and IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine booster immunization on mice .We randomly divided the mice into 7 groups ,namely PBS negative controls ,BCG controls ,pcAg85A controls ,BCG primary immunization combined with Ag85A booster immunization controls ,BCG primary immunization combined with Ag85A and IL-12 booster immunization controls , BCG primary immunization combined with IL-12 booster immunization controls ,and BCG primary immunization combined with pcDNA3 .1 booster immunization controls .Implementing the immune in procedure of BCG primary immunization and cytokine IL-12 booster immunization combined with mycobacterium tuberculosis Ag85A DNA ,we observed the immune effect on mice by detecting the mice serum total IgG , specific lymphocyte proliferation and cytokine levels in 4 ,6 ,8 weeks after the last immunization .Comparing the mice immunized in the strategy of BCG primary immunization and cytokine IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine strengthening immunization to the mice in other groups by other immune ways ,we found that ,in BCG/Ag85A+ IL-12 groups ,IgG in-creased significantly (P＜ 0 .05) ,specific lymphocyte prolifera-ted significantly ,and after strengthening immunization IFN-γlevels ,IL-2 levels and IL-4 levels in the three periods were 128 .2 ±20.4,190.2±16.51,244.2±39.14 ;146.2±17.29,271.6±16.36and16.36±28.12 ;68.6±6.62,96.6±5.5and5.5± 10 .71 ,respectively ,which were higher than those in other groups (P＜0 .05) .It’s suggested that the immunization way of BCG primary immunization and cytokine IL-12 combined with Mycobacterium tuberculosis Ag85A DNA vaccine booster immu-nization could significantly enhance the humoral and cellular immunity of the bodies ,and provide the basis for further study on protective effect test in animals .
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Objective: To optimize the Shenzhen universal infant hepatitis B immunization method. Methods: To analyze the long effectiveness of different immunization strategies and disease transition after hepatitis B virus infection by using cost-effectiveness method through decision-tree and Markov models among the Shenzhen newborns cohort in 2010 based on the local parameters. Results:Through the current strategies, the program of screening all pregnant women for HBsAg and vaccinating newborns of single-positive mothers combing with HBIG and vaccine would not only prevent more new cases, hepatic carcinoma and related deaths; but also gain more living years and QALYs. From the social prospect, it will save about RMB 40 million compared with the current program. Conclusion: It is suggested that Shenzhen Government should amend the current universal infant hepatitis B immunization program to gain more economic and social benefits.
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Objective To investigate the boosting efficiency of a subunit vaccine consisting of the fusion protein Ag85B-Mpt64190-198-Mth8.4 (AMM) , dimethyl-dioctyldecyl ammonium bromide (DDA) and BCG polysaceharide nucleic acid (BCG-PSN) on the primed inoculation with BCG. Methods The AMM subunit vaccine was composed of fusion protein AMM, adjuvant DDA and BCG-PSN. The first mouse experi-mental group was immunized with BCG first, then boosted with the AMM subanit vaccine in the 10th week. The second experimental group was boosted with the AMM subunit vaccine in the 8th week and the 10th week respectively with a two weeks interval after the primed with BCG. Two control groups were treated re-spectively with physiological saline alone and BCG alone. After the primed inoculation, ELISPOT and ELISA were used for the detection of the cell-mediated and humoral immune response in week 14 and week 22 re-spectively. Furthermore, the immunized mice were challenged with live BCG to mimic tuberculosis infection in the 22nd week after the primed inoculation. Subsequently the T cell typing and humoral response were de-tected by flow cytometry and ELISA, respectively. Results ( 1 ) The level of secreting IFN-γ: 14 weeks af-ter the primed inoculation,with the stimulation of the specific antigen-Ag85B, the number of cells secreting IFN-γ in the second experimental group (135±14) was more than BCG alone immunized group (19±16), t = 10. 98, P < 0.01. In the 22nd week, the number of cells secreting IFN-γ in the second experimental group (208±11) was still more than BCG alone group (57±18), t =6.43, P <0.01. (2) The level of humoral immune response: the IgG1 antibody titer in the second experimental group was obviously higher than that in the first experimental group. However, the ratio of IgG2a to IgG1, as the index reflecting the Thl-type immune response, in the experimental group 2 was lower than that in the experimental group 1. (3) The contents of CD4+ CD25+ T cells after challenged with live BCG strain: the first and the second ex-perimental groups were both higher than the BCG alone group (t1 = 3.08, t2 = 3.16, P < 0.05 ). Conclu-sion Boosting the BCG-pfimed mice with tuberculosis AMM subunit vaccine twice can induce higher level of cell-mediated and humoral immune response than BCG alone, which could activate the regulative immune response at the same time.
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Objective To explore the immunization strategy at the endgame of poliomyelitis eradication in China.Methods To search the related study databases by the mean of evidence based medicine,and to investigate the update status of production and usage of polio vaccine in China.The general prospective analysis was conducted on aspects of the comparison of different immunization strategies,the feasibility of oral poliovirus vaccine(OPV)switching to Sabin strain inactivated poliovirus vaccine(Sabin-IPV)and the Sabin-IPV immunization schedule.Results The immunization strategy of OPV switching to IPV should be considered to choose in China because the domestic Sabin-IPV products will be registered soon and the switching feasibility is already provided with the conditions of police,technique,vaccine supply,and other guarantee.The routine immunization of Sabin-IPV can be carried out referring to the update OPV immunization schedule.Conclusion The study on immunization strategy at the endgame of poliomyelitis eradication should be further enhanced and the preparation of OPV switching Sabin-IPV should be considered in China.
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Objective:To investigate the immune efficacy after sequential immunization with Mycobacterium tuberculosis DNA vaccine encoding mature form of Ag85B(pTB30m)and Mycobacterium tuberculosis H37Ra in mice.Methods:Much of highly pure plasmid DNA(pTB30m)extracted by alkaline lysis method was confirmed by restriction endonuclease digestion.Then,its DNA concentration and purity were determined by UV spectrophotometry.At various intervals(4weeks,8weeks)after sequential immunization,ELISA was used to detect the level of the serum antibody against PPD.Also,the spleen lymphocytes of mice were cultured with PPD in vitro.Lymphocyte transformation was detected by MTT assay.Results:Prepared pTB30m was highly pure and came to the needed concentration.Compared with Group Naive control,the specific antibody levels against PPD and the stimulation index(SI)of spleen lymphocytes were all statistically higher in Group DNA-85B/H37Ra(P0.05),as compared with Group DNA-85B/BCG,Group H37Ra and Group BCG,However,compared with Group H37Ra and Group BCG,the SI of mice was significantly larger in Group DNA-85B/H37Ra(P