Research progress on vaccines against human respiratory syncytial virus / 中国生物制品学杂志

@#Human respiratory syncytial virus(hRSV)is one of the main pathogens that cause lower respiratory tract infection in infants and the elderly.hRSV genome contains 10 genes with a full length of 15 222 bp,encoding 11 proteins(9structural proteins and 2 non-structural proteins).Different proteins play different roles in the pathogenesis of hRSV.With the in-depth research on the biological and structural characteristics of hRSV,various types of hRSV vaccines have been developed,making rapid progress.For example,hRSV attenuated live vaccine hRSV ?NS2/?1313/I1314L has entered Phase II clinical trial,and hRSV subunit protein vaccine Pre-F-GCN4t has entered Phase III clinical trial.In this paper,the biological characteristics of hRSV and the types of hRSV vaccines with rapid progress are reviewed so as to provide a reference for the development of hRSV vaccines in China.

Bilateral choroidal effusion following vaccination against SARS-CoV-2 virus

An 80-year-old systemically stable female presented with sudden blurring of vision post the first dose of Covishield™, a non-replicating viral vector vaccine. On examination, she was found to have bilateral serous choroidal effusions. A thorough systemic and ocular workup was performed to rule out other causes of choroidal effusion. The effusions resolved with tapering doses of oral and systemic steroids. To the best of our knowledge, at the time of submission, this is the first case of choroidal effusion being reported after the coronavirus disease 2019 (COVID-19) vaccine.

Development and application of real-time qPCR assay for detecting Sendai virus gene copy number / 中华实验和临床病毒学杂志

Objective@#To develop a real-time quantitative PCR (qPCR) assay for detecting Sendai virus gene copy number.@*Methods@#The recombinant plasmid was constructed and a reference used to establish the real-time qPCR method with the TaqMan probe and verified for reproducibility and sensitivity.@*Results@#The linear range of the developed real-time qPCR assay was 1.024 × 103 ~5 × 1010 copies/μl, with an R2 value of more than 0. 99. The standard recovery of the tested samples was 84.56%~119.48%.@*Conclusions@#Compared with traditional hernagglutination assay for particle number detection, this method has higher sensitivity, better repeatability and high quantitative accuracy. It can be used for the detection of particle number of vaccine with sendai virus as the carrier, so as to detect the specific activity of vaccine products.

Application of lysis system in bacterial vector vaccines / 生物工程学报

Recombinant bacterial vector vaccines have been widely used as carriers for the delivery of protective antigens and nucleic acid vaccines to prevent certain infectious diseases because of their ability to induce mucosal immunity, humoral immunity and cellular immunity. However, protective antigens and nucleic acids recombined into bacterial vector vaccines are difficult to be released into host cells because of the presence of bacterial cell wall. Vaccine strains that are residual in animals or livestock products may also cause environmental contamination and spread of the vaccine strains. The effective solution for these problems is to construct an auto-lysis system that can regulate the vaccine strains to grow normally in vitro while lysis in vivo. The lysis systems that have been applied in germs mainly include: the lysis system based on regulated delayed peptidoglycan synthesis, the lysis system based on the regulation of bacteriophage lysis protein and the lysis system based on the toxin-antitoxin system. In addition, a potential lysis system based on bacterial Type Ⅵ Secretion System (T6SS) is also expected to be a new method for the construction of auto-lysis strains. This review will focus on the regulatory mechanisms of these bacterial lysis systems.

Advance in the development of modified vaccinia virus Ankara (MVA)vectors for novel influenza vaccines / 中国人兽共患病学报

Influenza,caused by influenza virus,is a respiratory infectious disease with a serious hazard to human health.Prevention of influenza through vaccine development is the most effective strategy.It is important to build a rapid response platform for research and production of influenza vaccine.As virus vectors,live vaccine provides a new prevention and treatment way for infectious disease.Modified vaccinia virus Ankara(MVA) is a replication-deficient viral vector that is safe and can encode one or more foreign antigens and induce humoral and cellular immune response.MVA holds great promise as a vaccine platform.In this review,we discuss the use of MVA for vaccine development against influenza virus.

Advances in the study of tuberculosis live vector vaccines / 中国人兽共患病学报

Currently,the BCG is used to prevent tuberculosis,but the immune effect is not ideal due to varied reasons.The existence of drug-resistant strains of tuberculosis and the increased prevalence and incidence of AIDS have leaded to the increased incidence of TB year by year.Therefore,the development of new tuberculosis vaccine is imminent In this paper,the latest research results in recent years for tuberculosis live vector vaccines were summarized,which provide a theoretical reference for further research and development of new TB vaccines.

Newcastle disease virus vectored vaccines as bivalent or antigen delivery vaccines

Recent advances in reverse genetics techniques make it possible to manipulate the genome of RNA viruses such as Newcastle disease virus (NDV). Several NDV vaccine strains have been used as vaccine vectors in poultry, mammals, and humans to express antigens of different pathogens. The safety, immunogenicity, and protective efficacy of these NDV-vectored vaccines have been evaluated in pre-clinical and clinical studies. The vaccines are safe in mammals, humans, and poultry. Bivalent NDV-vectored vaccines against pathogens of economic importance to the poultry industry have been developed. These bivalent vaccines confer solid protective immunity against NDV and other foreign antigens. In most cases, NDV-vectored vaccines induce strong local and systemic immune responses against the target foreign antigen. This review summarizes the development of NDV-vectored vaccines and their potential use as a base for designing other effective vaccines for veterinary and human use.

A review of vaccine development and research for industry animals in Korea

Vaccination has proven to be the most cost-effective strategy for controlling a wide variety of infectious diseases in humans and animals. For the last decade, veterinary vaccines have been substantially developed and demonstrated their effectiveness against many diseases. Nevertheless, new vaccines are greatly demanded to effectively control newly- and re-emerging pathogens in livestock. However, development of veterinary vaccines is a challenging task, in part, due to a variety of pathogens, hosts, and the uniqueness of host-susceptibility to each pathogen. Therefore, novel concepts of vaccines should be explored to overcome the limitation of conventional vaccines. There have been greatly advanced in the completion of genomic sequencing of pathogens, the application of comparative genomic and transcriptome analysis. This would facilitate to open opportunities up to investigate a new generation of vaccines; recombinant subunit vaccine, virus-like particle, DNA vaccine, and vector-vehicle vaccine. Currently, such types of vaccines are being actively explored against various livestock diseases, affording numerous advantages over conventional vaccines, including ease of production, immunogenicity, safety, and multivalency in a single shot. In this articles, the authors present the current status of the development of veterinary vaccines at large as well as research activities conducted in Korea.

Comparison of the immune effects of Coxsackievirus B3 VP1 protein, rAd/VP1 and pcDNA3/VP1 in mice / 中华微生物学和免疫学杂志

Objective To compare the immune effects of Coxsackievirus B3 (CVB3) capsid protein VP1 expressed bacterially, recombinant adenovirus rAd/VP1 and recombinant plasmid pcDNA3/VP1which express VP1 protein in mice. Methods After expressed in prokaryotic cells, VP1 protein was purified. Recombinant adenovirus rAd/VP1 and recombinant plasmid pcDNA3/VP1 were amplified and extracted. Six to 8-week-old, male BALB/c mice were divided into four groups randomly. Each group contained 18 mice. The mice of pcDNA3/VP1 group or VP1 protein group were immunized intramuscularly with three injections at three weeks apart, of recombinant plasmid pcDNA3/VP1 at a dose of 100 μg/mouse or recombinant protein VP1 at a dose of 50 μg/mouse. The mice of rAd/VP1 group were immunized intramuscularly twice at two weeks interval with rAd/VP1 at a dose of 1.2 × 107 PFU. The control group was mock-immunized with 100 μl of PBS intramuscularly. Mice were bled from the retroorbital sinus plexus every two weeks after each immunization. ELISA and micro-neutralization test were used to detect levels of CVB3-specific IgG antibody and neutralizing antibody titers in the sera of immunized mice. Three weeks after the last immunization, the cytotoxic T lymphocyte(CTL) killing activity of spleen lymphocytes was detected with CCK-8 assay. Subsequently, virus titers in the sera of immunized mice were determined by the 50% cell culture infective dose( CCID50 ) assay on HeLa cell monolayers and percentage of animals surviving were observed after lethal CVB3 attack over a period of 21 days. Results The titers of specific IgG antibody and neutralizing antibody in sera of VP1 protein immunized mice were higher than other groups( P ＜0.05 ). While CTL killing activity of spleen lymphocytes of VP1 protein immunized mice was lower than mice in rAd/VP1 group( P ＜0. 05). Virus titers in sera of VP1 protein immunized mice were lower than the mice in pcDNA3/VP1 or rAd/VP1 groups ( P ＜ 0.05 ), while survival rate was significantly higher than these two groups ( P ＜ 0.05 ).Conclusion VP1 protein induced higher level of humoral immune response and acquired obvious immune protection effects in mice. The immunizing potency of VP1 protein vaccine surpassed plasmid pcDNA3/VP1or recombinant adenovirus rAd/VP1. It appeared to be a promising candidate among the three different vaccines.

The immunological effect of Ad/MDC-VP1 combined with DNA vaccine against Coxsackievirus infection / 中华微生物学和免疫学杂志

Objective To construct recombinant adenovirus Ad/MDC-VP1 and investigate its im-muno-boosting effect of the mice primed with the experimental DNA vaccine against Coxsackievirus infection. Methods The recombinant adenovirus Ad/MDC-VP1 was constructed and packaged. The Western blot analysis was used to verify the target protein. BALB/c mice were divided into four groups: Ad/MDC-VP1 group, pcDNA3/MDC-VP1 group, pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost group and PBS group. The mice in each group were immunized intramuscularly. The titers of serum IgG and neutralizing antibody were tested by ELISA and trace neutralization assay, respectively. The lymphocytes proliferation activity and specific CTL cytotoxic activity were tested by CCK-8 assay. The mice in each group were challenged with le-thal dose of Coxsackievirus, and the assay of the serum virus titers and the observation of protection efficacy against Coxsackievirus infection were carried out. Results The recombinant adenovirus Ad/MDC-VP1 was successfully constructed and the target protein was expressed. It was observed that the titers of CVB3 VP1 specific antibody, lymphocyte stimulation index, CTL cytotoxicity activities and protection rate of the pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost group were much higher than those of the rest groups( P < 0.05), and the titer of serum virus was lower after CVB3 challenged ( P < 0.05 ). Conclusion Both the cellular and humoral immune responses in mice could been significantly enhanced by the pcDNA3/MDC-VP1 prime-Ad/MDC-VP1 boost strategy.

Progress in Vaccine Development of Hepatitis C Virus / 中国生物工程杂志

Hepatitis C virus (HCV) accounts for the majority of cases of transfusion acquired hepatitis and may cause chronic hepatitis, cirrhosis and hepatocellular carcinoma. Currently, there is no vaccine against HCV and treatment is expensive and not always effective.The adaptive host immune response in viral clearance of HCV infection was described and the recent progress in vaccine development of HCV, focusing on the fields of DNA vaccine candidates, recombinant viral vectored vaccine candidates and combined (prime-boost) vaccine candidates were summarized. Some challenges and limitations of developing a HCV vaccine were also analysed. In summary, a promising approach of developing an experimental HCV vaccine to induce extremely potent and broad T-cell responses based on prime-boost strategy was presented.