Bio-mineralization has emerged as a promising strategy to enhance vaccine immunogenicity. This study optimized the calcium phosphate (CaP) mineralization process of foot-and-mouth disease virus-like particles (FMD VLPs) to achieve high mineralization efficiency and scalability. Key parameters, including concentrations of Ca²⁺, HPO₄^2-, NaCl, and VLPs, as well as stirring speed, were systematically optimized. Stability of the scaled-up reaction system and immunogenicity of the mineralized vaccine were evaluated. Optimal conditions [25.50 mmol/L Ca(NO₃)₂, 15 mmol/L Na₂HPO₄, 300 mmol/L NaCl, 0.75 mg/mL VLPs, and 1 500 r/min] yielded CaP-mineralized VLPs (VLPs-CaP) with high mineralization efficiency, uniform morphology, and a favorable particle size. Scaling up the reaction by 25 folds maintained consistent mineralization efficiency and particle characteristics. Immunization in mice demonstrated that VLPs-CaP induced higher titers of specific antibodies and neutralizing antibodies than unmineralized VLPs (P < 0.05). Higher IgG2a/IgG1 ratio and enhanced IFN-γ secretion (P < 0.05) further indicated robust cellular immune responses. We establish a stable and scalable protocol for VLPs-CaP, providing a theoretical and technical foundation for developing high-efficacy VLPs-CaP vaccines.
Vaccines, Virus-Like Particle/immunology* ; Immunogenicity, Vaccine ; Calcium Phosphates/chemistry* ; Foot-and-Mouth Disease Virus ; Biomineralization ; Particle Size ; Animals ; Mice ; Antibodies, Neutralizing/blood* ; Antibodies, Viral/blood* ; Immunity, Cellular

Vaccination is a crucial strategy for the prevention and control of infectious diseases. Virus-like particles (VLPs), composed of structural proteins, have garnered significant attention as a novel type of vaccine due to their excellent safety and immunogenicity. However, similar to most vaccine antigens, VLPs exhibit insufficient thermal stability, which not only restricts the widespread application of vaccines but also increases the risk of vaccine inactivation. This study aims to enhance the stability and shelf life of VLPs derived from type A foot-and-mouth disease virus (FMDV) by employing vacuum freeze-drying technology. The optimal lyoprotectant formulation was determined through single-factor and combinatorial screening. Subsequently, the correlation between the immunogenicity of the freeze-dried vaccine and the content of FMDV VLPs was evaluated via a mouse model. The stability of FMDV VLPs before and after freeze-drying was further assessed by storing them at 4, 25, and 37 ℃ for varying time periods. Results indicated that the lyoprotectant formulation No.1, composed of 7.5% trehalose, 0.1% Tween 80, 50 mmol/L glycine, 1% sodium glutamate, and 3% polyvinylpyrrolidone (PVP), effectively preserved the content of FMDV VLPs during the vacuum freeze-drying process. The immunization trial in mice revealed that the levels of specific antibodies, immunoglobulin G1 (IgG1), interleukin-4 (IL-4), and neutralizing antibodies induced by freeze-dried FMDV VLPs were comparable to those induced by non-freeze-dried FMDV VLPs. The heat treatment results showed that the storage periods of freeze-dried FMDV VLPs at 4, 25, and 37 ℃ were significantly longer than those of non-freeze-dried FMDV VLPs. In conclusion, the selected lyoprotectant formulation effectively improved the stability of FMDV VLPs vaccines. This study provides valuable insights for enhancing the stability of novel subunit vaccines.
Freeze Drying/methods* ; Animals ; Foot-and-Mouth Disease Virus/immunology* ; Mice ; Vaccines, Virus-Like Particle/chemistry* ; Foot-and-Mouth Disease/immunology* ; Vacuum ; Drug Stability ; Mice, Inbred BALB C ; Viral Vaccines/immunology*

This study developed ferritin-based nanoparticles carrying the African swine fever virus (ASFV) p30 protein and evaluated their immunogenicity, aiming to provide an experimental basis for the research on nanoparticle vaccines against ASFV. Initially, the gene sequences encoding the p30 protein and SpyTag were fused and inserted into the pCold-I vector to create the pCold-p30 plasmid. The gene sequences encoding SpyCatcher and ferritin were fused and then inserted into the pET-28a(+) vector to produce the pET-F-np plasmid. Both plasmids were expressed in Escherichia coli upon induction. Subsequently, the affinity chromatography-purified p30 protein was conjugated with ferritin in vitro, and the p30-ferritin (F-p30) nanoparticles were purified by size-exclusion chromatography. The morphology and structural integrity of F-p30 nanoparticles were examined by a particle size analyzer and transmission electron microscopy. Mice were immunized with F-p30 nanoparticles, and the humoral and cellular immune responses were assessed. The results showed that F-p30 nanoparticles were successfully prepared, with the particle size of approximately 20 nm. F-p30 nanoparticles were efficiently internalized by bone marrow-derived dendritic cells (BMDCs) cells in vitro. Compared with the p30 protein alone, F-p30 nanoparticles induced elevated levels of specific antibodies and cytokines in mice and stimulated the proliferation of follicular helper T cell (T_FH) and germinal center B cell (GCB) in lymph nodes as well as CD4⁺ and CD8⁺ T cells in the spleen. In conclusion, we successfully prepared F-p30 nanoparticles which significantly enhanced the immunogenicity of p30 protein, giving insights into the development of vaccines against ASFV.
Animals ; Nanoparticles/chemistry* ; Mice ; African Swine Fever Virus/genetics* ; Ferritins/chemistry* ; Swine ; Viral Vaccines/genetics* ; African Swine Fever/immunology* ; Mice, Inbred BALB C ; Viral Proteins/genetics* ; Escherichia coli/metabolism* ; Dendritic Cells/immunology* ; Immunogenicity, Vaccine ; Antibodies, Viral/blood* ; Female ; Capsid Proteins/genetics*

Pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection emerged in Wuhan City, Hubei Province, China in December 2019. By Feb. 11, 2020, the World Health Organization (WHO) officially named the disease resulting from infection with SARS-CoV-2 as coronavirus disease 2019 (COVID-19). COVID-19 represents a spectrum of clinical manifestations that typically include fever, dry cough, and fatigue, often with pulmonary involvement. SARS-CoV-2 is highly contagious and most individuals within the population at large are susceptible to infection. Wild animal hosts and infected patients are currently the main sources of disease which is transmitted via respiratory droplets and direct contact. Since the outbreak, the Chinese government and scientific community have acted rapidly to identify the causative agent and promptly shared the viral gene sequence, and have carried out measures to contain the epidemic. Meanwhile, recent research has revealed critical aspects of SARS-CoV-2 biology and disease pathogenesis; other studies have focused on epidemiology, clinical features, diagnosis, management, as well as drug and vaccine development. This review aims to summarize the latest research findings and to provide expert consensus. We will also share ongoing efforts and experience in China, which may provide insight on how to contain the epidemic and improve our understanding of this emerging infectious disease, together with updated guidance for prevention, control, and critical management of this pandemic.
Amino Acid Motifs ; Animals ; Antiviral Agents ; Betacoronavirus ; genetics ; China ; epidemiology ; Communicable Disease Control ; methods ; Coronavirus Infections ; diagnosis ; epidemiology ; physiopathology ; prevention & control ; therapy ; Humans ; Immunization, Passive ; Medicine, Chinese Traditional ; Pandemics ; Pneumonia, Viral ; diagnosis ; epidemiology ; physiopathology ; therapy ; Protein Domains ; Spike Glycoprotein, Coronavirus ; chemistry ; Viral Vaccines

Rotavirus is the leading causal agent of severe acute gastroenteritis in children aged <5 years. A specific pharmacologic agent for the treatment of rotavirus-infected children is lacking. In China, only the Luo Tewei oral vaccine (Lanzhou Institute of Biological Products, Shanghai, China), which is produced from Lanzhou lamb rotavirus vaccine (LLR), is available. Studies have hypothesized that the genotype of LLR is G10P[12], To identify the genotype of LLR by reverse transcription-polymerase chain reaction, we showed that the VP7 and VP4 genotypes of LLR were G10 and P[15], respectively, based on sequencing, alignment and phylogenetic analyses. In conclusion, we identified the genotype of rotavirus strain LLR to be G10P[15].
China ; Genotype ; Humans ; Molecular Sequence Data ; Phylogeny ; Rotavirus ; chemistry ; classification ; genetics ; isolation & purification ; Rotavirus Infections ; virology ; Rotavirus Vaccines ; chemistry ; classification ; genetics ; isolation & purification ; Sequence Homology, Amino Acid ; Viral Proteins ; chemistry ; genetics

To evaluate the immunities of biodegradable microsphere as a release delivery system for DNA vaccine against Infectious Bursal Disease Virus, in our study, silk fibroin/chitosan microsphere adjuvant was prepared with a precipitation/coacervation method. Both glutaraldehyde and Na2SO4 solution were used in cross-linking. No immune chicken were intramuscularly inoculated at 14 day-old and boosted 2 weeks later. The results show that glutaraldehyde destroyed the DNA activity of the vaccine whereas Na2SO4 solution did not. Factors of the chitosan concentration 0.5% (pH 5.0), silk fibroin concentration 0.6%, plasmid DNA (500 microg/mL) dissolved in 2% Na2SO4 solution were optimized to produce microsphere, with a loading capacity of 89.14%. The average particle size of SF-CS/pCI-VP2/4/3 microsphere is 1.98 microm, and it can protect the loading DNA vaccine from DNase I digestion. Data from anti IBDV ELISA antibodies in the serum show that immunization activity of the microsphere groups were generally higher than plasmid vaccine group (P < 0.05), and the SF/CS compound microspheres group was better than that of sole CS microsphere group. The developed SF/CS microspheres are a very promising vaccine delivery system.
Adjuvants, Immunologic ; chemistry ; Animals ; Birnaviridae Infections ; prevention & control ; veterinary ; Chickens ; Chitosan ; chemistry ; Fibroins ; chemistry ; Infectious bursal disease virus ; Microspheres ; Plasmids ; Poultry Diseases ; prevention & control ; Vaccines, DNA ; chemistry ; Viral Vaccines ; chemistry

Dengue virus (DENV) is a re-emerging disease transmitted by the Aedes mosquitoes and has become a major public health problem in southern China. Currently, no antiviral drug or effective vaccine exist to control this disease. The chimeric DENV structural protein vaccine cannot elicit balanced levels of protective immunity to each of the four viral serotypes; therefore, non-structural protein components may be required to construct an effective DENV vaccine. The Dengue virus non-structural 1 (DENV NS1) protein plays a critical role in viral pathogenesis and protective immunity. Therefore, immunity to Dengue 1-4 NS1 subtypes may be crucial for the prevention of severe disease. This review attempts to provide an overview about the structure and function of DENV NS1.
Animals ; Dengue ; immunology ; prevention & control ; virology ; Dengue Vaccines ; chemistry ; genetics ; immunology ; Dengue Virus ; chemistry ; genetics ; immunology ; Humans ; Viral Nonstructural Proteins ; chemistry ; genetics ; immunology

Antibodies, Monoclonal ; chemistry ; immunology ; Antigens, Viral ; chemistry ; genetics ; immunology ; Binding Sites ; Capsid Proteins ; chemistry ; genetics ; immunology ; Epitopes ; chemistry ; genetics ; immunology ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Hepatitis E ; immunology ; prevention & control ; virology ; Hepatitis E virus ; chemistry ; immunology ; Humans ; Molecular Docking Simulation ; Mutagenesis, Site-Directed ; Peptide Mapping ; Protein Binding ; Recombinant Proteins ; chemistry ; genetics ; immunology ; Viral Hepatitis Vaccines ; administration & dosage ; biosynthesis

OBJECTIVETo evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine.

METHODSIn a multicenter, double-blind, randomized, placebo-controlled trial, participants received two doses of split-virion formulation containing 15 μg hemagglutinin antigen, with or without aluminum hydroxide (Al-OH). We classified the participants into six age categories (>61 years, 41-60 years, 19-40 years, 13-18 years, 8-12 years, and 3-7 years) and obtained four blood samples from each participant on days 0, 21, 35, and 42 following the first dose of immunization. We assessed vaccine immunogenicity by measuring the geometric mean titer (GMT) of hemagglutination inhibiting antibody. We used a two-level model to evaluate the fixed effect of aluminum Al-OH and other factors, accounting for repeated measures.

RESULTSThe predictions of repeated measurement on GMTs of formulations with or without Al-OH, were 80.35 and 112.72, respectively. Al-OH significantly reduced immunogenicity after controlling for time post immunization, age-group and gender.

CONCLUSIONThe Al-OH adjuvant does not increase but actually reduces the immunogenicity of the split-virion pH1N1 vaccine.

Adjuvants, Pharmaceutic ; chemistry ; Adolescent ; Adult ; Aluminum Hydroxide ; chemistry ; Antibodies, Viral ; blood ; Child ; Child, Preschool ; China ; Data Interpretation, Statistical ; Double-Blind Method ; Female ; Hemagglutination Inhibition Tests ; Humans ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza Vaccines ; adverse effects ; chemistry ; immunology ; Influenza, Human ; epidemiology ; immunology ; prevention & control ; virology ; Male ; Middle Aged ; Models, Statistical ; Pandemics ; Young Adult

Codon ; Computational Biology ; methods ; Evolution, Molecular ; Influenza A virus ; classification ; genetics ; Influenza Vaccines ; immunology ; Molecular Biology ; Phylogeny ; RNA, Viral ; chemistry ; Viral Proteins ; chemistry