The present invention provides attenuated P. multocida strains that elicit an immune response in animal P. multocida, compositions comprising said strains, methods of vaccination against P. multocida, and kits for use with such methods and compositions. The invention further provides novel, genetically-engineered mutations in P. multocida hyaD and nanPU genes, which are useful in the production of novel attenuated P. multocida bacterial strains.

The present disclosure describes deoptimized foot and mouth viruses and their use for prophylactic and therapeutic treatment of mammalian subjects. The recombinant viruses provided herein include alterations in several genomic regions as well as Differentiating Infected from Vaccinated Animals (DIVA) markers.

The present invention relates to modified poxviral vectors and to methods of making and using the same. In particular, the invention relates to recombinant modified vaccinia virus Ankara-based (MVA-based) vaccine against FMDV infection and to related products, methods and uses. Specifically, the present invention relates to genetically engineered (recombinant) MVA vectors comprising at least one heterologous nucleotide sequence encoding an antigenic determinant of a FMDV protein. The invention also relates to products, methods and uses thereof, e.g., suitable to induce a protective immune response in a subject.

A method of producing purified FMDV VLPs, comprising contacting cells containing FMDV VLPs with a lysis buffer and allowing the cells to lyse, the lysis buffer comprising 10-20 mM Tris-HCl, 150-200 mM NaCl, 3 mM MgCl.sub.2, and 1% Triton X-100, wherein the lysis buffer does not contain EDTA; centrifuging a solution; and removing a supernatant from the solution, the supernatant containing the purified FMDV VLPs.

The present invention provides a Hansenula engineering fungus that efficiently expresses CA10 virus-like particles and use thereof. The engineering fungus comprises a recombinant vector carrying P1 and 3CD genes of the CA10 virus, and the starting strain of the engineering fungus is uracil auxotroph. The Hansenula AU-0501, P1 and 3CD genes are optimized according to preferred codons of Hansenula. The present invention also provides a preparation method of CA10 virus-like particles, comprising: culturing engineering fungi, expressing CA10 virus-like particles, and separating and purifying virus-like particles by ultrafiltration and three-step chromatography. The CA10 virus-like particles provided by the present invention and the vaccine prepared therefrom have good immunogenicity, safety and biological activity, the process is simple, the chromatography method is adopted for purification, and large-scale preparation and purification can be realized to obtain a VLP protein stock solution with high purity (greater than 99%), which can be used to prepare a vaccine to prevent CA10 infection, with good economic value and application prospects.

A method of producing purified FMDV VLPs, comprising contacting cells containing FMDV VLPs with a lysis buffer and allowing the cells to lyse, the lysis buffer comprising 10-20 mM Tris-HCl, 150-200 mM NaCl, 3 mM MgCl.sub.2, and 1% Triton X-100, wherein the lysis buffer does not contain EDTA; centrifuging a solution; and removing a supernatant from the solution, the supernatant containing the purified FMDV VLPs.

The present disclosure belongs to the technical field of biological products for veterinary medicine, and specifically relates to a recombinant foot-and-mouth disease virus (FMDV) with a reduced immunosuppressive activity, a preparation method and use thereof, and a recombinant vaccine strain. According to the present disclosure, it is firstly discovered that FMDV 3B protein has an immunosuppressive function, and key sites for exerting the immunosuppressive function are found. A recombinant FMDV vaccine strain with a lost immunosuppressive function in FMDV 3B protein is constructed by introducing amino acid mutations into three repeated copies of FMDV 3B protein.

Provided is a method to generate a recombinant virus that can stably express target proteins. The recombinant virus of the present invention is useful for producing an immunogenic composition or vaccine.

Provided herein is a nucleic acid comprising consensus amino acid sequence of foot-and-mouth disease FMDV VP1-4 coat proteins of FMDV subtypes A, Asia 1, C, O, SAT1, SAT2, and SAT3 as well as plasmids and vaccines expressing the sequences. Also provided herein is methods for generating an immune response against one or more FMDV subtypes using the vaccine as described above as well as methods for deciphering between vaccinated mammals with the vaccine and those that are infected with FMDV.

Synthetic alphavirus-derived replicon expression systems comprising nucleic acid sequences encoding at least one modified nonstructural protein, and synthetic nucleic acid sequences encoding at least one heterologous protein are described. Methods of producing at least one heterologous protein in a cell, or of inducing an immune response in a subject by administering and/or expressing the synthetic alphavirus-derived replicon expression systems are provided.