Provided, herein, in certain embodiments are virus-like particles such as synthetic enveloped VLPs or synthetic membrane VLPs. In some embodiments, the VLPs comprise a lipid bilayer. In some embodiments, the VLPs comprise a purified antigen anchored to the lipid bilayer. Some embodiments relate to vaccines comprising the VLP, methods of using the vaccine, and methods of making the vaccine or VLP.

The present invention is directed to methods and compositions of RNA nanostructures for replication and/or subgenomic expression of gene modulating single-stranded RNA by RNA-directed RNA polymerase-like proteins and the use of such nanostructures for use in a variety of organisms.

The present disclosure provides compositions and methods for detecting the presence of neutralizing antibodies in a sample. Unlike conventional assays, the methods provided herein do not require the use of live virus or virus pseudoparticles to identify neutralizing antibodies.

Disclosed herein include methods, compositions, and kits suitable for use in vaccination. There are provided, in some embodiments, nucleic acid compositions (e.g., mRNA vaccine, DNA vaccine) comprising a polynucleotide encoding a fusion protein. The fusion protein can comprise an antigenic polypeptide (AP) and an endosomal sorting complex required for transport (ESCRT)-recruiting domain (ERD). A plurality of fusion proteins can be capable of self-assembling into an enveloped nanoparticle (ENP) secreted from a cell in which the fusion proteins are expressed. There are provided, in some embodiments, populations of ENPs.

The present invention relates i.a. to a recombinant avian coronavirus spike protein or fragment thereof comprising a mutation at amino acid position 267 to Cysteine. Further, the present invention relates to an immunogenic composition comprising an avian coronavirus with such spike protein.

The present invention provides a SARS-CoV-2 chimeric VLP vaccine composition and an expressing vector and use thereof. The chimeric SARS-CoV-2 VLP comprises a VLP skeleton formed by the M1 protein and the M2 protein of influenza virus, and the chimeric spike protein of SARS-CoV-2, expressed on the surface of the VLP skeleton, the transmembrane domain of which is replaced by the transmembrane domain of a HA of influenza virus. The present invention also provides a recombinant vector expressing the chimeric SARS-CoV-2 VLP, and the use of the chimeric SARS-CoV-2 VLP for eliciting an immune response against SARS-CoV-2 variants.

Severe Acute Respiratory Syndrome Coronavirus 2 antigen virus-like particles (VLPs) and recombinant immune complexes (RICs) are described, along with methods of making said VLPs and RICs in plants and using said VLPs and RICs to induce an immune response in a subject.

The present invention provides myxoma viral vectors that encode severe acute respiratory syndrome coronavirus 2 antigens and that can facilitate expression and secretion of virus-like particles (VLPs). Also provided are methods of making said VLPs in mammalian cells and using said VLPs and myxoma viral vectors to induce an immune response in a subject.

This disclosure relates to methods of promoting immune responses against coronavirus, such as SARS-CoV-2, and compositions related thereto. In certain embodiments, this disclosure relates to methods of vaccinating for coronavirus comprising administering to the subject a composition disclosed herein. In certain embodiments, the composition comprises a recombinant virus such as recombinant MVA that encodes a coronavirus spike protein. In certain embodiments, the coronavirus spike protein comprises a proline mutation at position 986. In certain embodiments, the coronavirus spike protein comprises a proline mutation at position 987.

The present disclosure provides expression vectors and bacterial sequence-free vectors, such as ministring DNA (msDNA), for producing virus-like particles (VLPs) as well as compositions and methods thereof. In some aspects, the methods include treating viral infections in subjects with the vectors, compositions, and VLPs.