Novel nanoparticle fusion proteins comprising proteins or peptides fused to Dps (DNA binding protein from starved cells) proteins are provided which bring forth distinct advantages for development of new and improved vaccines, diagnostic tests, and other biomedical products.

The present invention provides a recombinant viral vector, an immunogenic composition containing the same, and the use thereof. The recombinant viral vector comprises a polynucleotide encoding a fusion peptide of CD4 helper T cell epitopes, the epitope fusion peptide comprising a cytomegalovirus epitope and/or an influenza virus epitope. The epitope fusion peptide and the recombinant viral vector provided by the present invention can improve the level of cellular immune response to a target immunogen, particularly to a weak immunogen, and overcome the immune tolerance of immune system to an antigen, particularly to a tumor antigen or an infection-related antigen. The products of the present invention are suitable for enhancing the efficacy of vaccines.

The disclosure relates to a polypeptide comprising, or consisting of, the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 9 or a sequence having at least 97%-100% sequence identity to one of SEQ ID NO: 1, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 9 for use as an immunogen for the purpose of eliciting an immune response in a subject susceptible to infection with a coronavirus. The disclosed polypeptide is further useful in reducing the severity of symptoms associated with a coronavirus infection. In addition to use in a protein-based vaccine, the polypeptide of the disclosure can be encoded by a nucleic acid/ribonucleic acid and used in a nucleic acid vaccine or viral vector vaccine.

Disclosed are peptides comprising a monomeric Fc fragment of an immunoglobulin recognized by a neonatal receptor (FcRn); an influenza HA protein; and a trimerization domain. Disclosed are compositions comprising one or more of the peptides described herein. Disclosed are nucleic acid sequences capable of encoding any one of the peptides described herein. Disclosed are methods for eliciting a protective immune response against influenza comprising administering to a subject an effective amount of a composition comprising a monomeric Fc fragment of an immunoglobulin recognized by a FcRn; an influenza HA protein; and a trimerization domain, wherein the administering is to a mucosal epithelium. Disclosed are methods of treating a subject exposed to influenza or at risk of being exposed to influenza comprising administering to the subject an effective amount of a composition comprising a monomeric Fc fragment of an immunoglobulin recognized by a FcRn; an influenza HA protein; and a trimerization domain, wherein the administering is to a mucosal epithelium.

Modified influenza virus neuraminidases are described herein that improve viral replication, thus improving the yield of vaccine viruses. Expression of such modified neuraminidases by influenza virus may also stabilize co-expressed hemagglutinins so that the hemagglutinins do not undergo mutation or decrease the need for HA binding to cells.

A method for synthesizing influenza virus-like particles (VLPs) within a plant or a portion of a plant is provided. The method involves expression of influenza HA in plants and the purification by size exclusion chromatography. The invention is also directed towards a VLP comprising influenza HA protein and plant lipids. The invention is also directed to a nucleic acid encoding influenza HA as well as vectors. The VLPs may be used to formulate influenza vaccines, or may be used to enrich existing vaccines.

The present invention provides, among other things, a novel and improved method for generating “mosaic” influenza antigenic polypeptides including hemagglutinin (HA) and neuraminidase (NA) polypeptides based on unique combination of epitope patterns that maximize exposure to epitopes present across multiple HA or NA sequences and therefore improved influenza strain coverage. In particular, the present invention provides engineered H1N1 influenza hemagglutinin (HA) polypeptides that are comprised of novel combinations of protective epitopes and antigenic regions from multiple H1N1 viral strains. Such engineered HA polypeptides have improved properties over HA polypeptides developed through conventional approaches that rely on consensus alignments of viral sequences.

This invention relates to chimeric virus-like particles (VLPs) assembled from a polypeptide comprising a papilloma virus (PV) L1 protein or L1/L2 protein and a target peptide comprising a CD8+ T cell epitope derived from a human pathogen. This invention also relates to methods using the chimeric VLPs as antigen-specific redirectors of immune responses.

This invention relates to chimeric virus-like particles (VLPs) assembled from a polypeptide comprising a papilloma virus (PV) L1 protein or L1/L2 protein and a target peptide comprising a CD8+ T cell epitope derived from a human pathogen. This invention also relates to methods using the chimeric VLPs as antigen-specific redirectors of immune responses.

The disclosure relates to the technical field of veterinary biological products, and discloses an avian influenza and fowl adenovirus type 4 bi-combined genetic engineering subunit vaccine. An antigen in the vaccine is a fusion antigen; the fusion antigen has a) avian influenza virus HA protein; b) fowl adenovirus fiber2 protein; c) a specific linker peptide located between the avian influenza virus HA protein and the fowl adenovirus fiber2 protein; the amino acid sequence of the specific linker peptide is as shown in SEQ ID NO:2. This vaccine contains the fusion antigen which can induce poultries to produce a high-level specific antibody to protect poultries from avian influenza and fowl adenovirus infection. Meanwhile, the disclosure also discloses a method for preparing the vaccine.