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.

A test strip for detecting a serotype O foot-and-mouth disease, the test strip including: a bottom board; a detection layer being disposed on the bottom board and including a detection line and a control line; an absorbent layer being disposed at one end of the detection layer close to the control line; a gold colloidal conjugate pad being disposed at the other side of the detection layer close to the detection line; and a sample pad is disposed on a top of the gold colloidal conjugate pad. The gold colloidal conjugate pad is coated with colloidal gold particles that are conjugated with a Staphylococcus protein A (SPA) marker. The detection line is coated or impregnated with serotype O FMDV-like particles, and the control line is coated or impregnated with rabbit IgG.

A method for preparing serotype O foot-and-mouth disease virus-like particles, the method including: construction of small ubiquitin-like modifier fusion expression vector, construction of recombinant expression vectors, construction of recombinant co-expression vector, expression and purification of proteins, and in-vitro assembly of serotype O foot-and-mouth disease virus-like particles. The disclosure also provides a test strip for detecting serotype O foot-and-mouth disease including a bottom board, and a detection layer disposed on the top of the bottom board. A detection line and a control line are disposed on the detection layer. An absorbent layer is disposed at one end of the detection layer close to the control line, and an immuno-gold pad is disposed at the other side of the detection layer close to the detection line. A sample pad is disposed on the top of the immuno-gold pad.

The present disclosure relates to hand, foot, and mouth disease vaccines and immunogenic compositions having one or more antigens from at least one virus that causes hand, foot, and mouth disease in humans, and methods of manufacture, formulation, and testing, and uses thereof.

A method for preparing serotype O foot-and-mouth disease virus-like particles, the method including: construction of small ubiquitin-like modifier fusion expression vector, construction of recombinant expression vectors, construction of recombinant co-expression vector, expression and purification of proteins, and in-vitro assembly of serotype O foot-and-mouth disease virus-like particles. The disclosure also provides a test strip for detecting serotype O foot-and-mouth disease including a bottom board, and a detection layer disposed on the top of the bottom board. A detection line and a control line are disposed on the detection layer. An absorbent layer is disposed at one end of the detection layer close to the control line, and an immuno-gold pad is disposed at the other side of the detection layer close to the detection line. A sample pad is disposed on the top of the immuno-gold pad.

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.

The present invention provides a recombinant foot and mouth disease virus (FMDV) capsid precursor protein comprising a modified VP1 protein and optionally further comprising a modified VP4 protein. The invention further relates to an isolated nucleic acid molecule and an expression vector comprising the nucleic acid molecule for recombinant expression of the modified capsid precursor protein. In further aspects, the invention relates to a virus-like particle (VLP) obtained from the modified capsid precursor protein and a vaccine for use in the protection of a subject against an infection with FMDV produced from the VLP.

The invention concerns a method of producing a foot and mouth disease virus (FMDV) virus-like particle (VLP) in a baculovirus expression system, the method comprising the steps of (i) infecting an insect cell with a baculovirus expression vector, (ii) culturing the insect cell in cell culture medium for 5 days or more post infection and (iii) harvesting the FMDV VLP from the cell culture medium. The invention further relates to a vaccine for use in the protection of a subject against an infection with FMDV, the vaccine being obtainable by the method of the invention.

The present disclosure relates to hand, foot, and mouth disease vaccines and immunogenic compositions having one or more antigens from at least one virus that causes hand, foot, and mouth disease in humans, and methods of manufacture, formulation, and testing, and uses thereof. Thus, there is a need to develop vaccines and immunogenic compositions for treating and/or preventing hand, food, and mouth disease, particularly in children. In order to meet this need, the present disclosure provides vaccines and immunogenic compositions for treating and/or preventing hand, foot, and mouth disease that include antigens from at least one virus that causes hand, foot, and mouth disease in humans, such as EV71, CA6, and CA16.

The invention concerns a method of producing a foot and mouth disease virus (FMDV) virus-like particle (VLP) in a baculovirus expression system, the method comprising the steps of (i) infecting an insect cell with a baculovirus expression vector, (ii) culturing the insect cell in cell culture medium for 4 days or more post infection, (iii) separating the insect cells from the cell culture to obtain cell-free cell culture medium, and (iv) harvesting the FMDV VLP from the cell-free cell culture medium. The invention further relates to a vaccine for use in the protection of a subject against an infection with FMDV, the vaccine being obtainable by the method of the invention.