Materials and methods are provided for making plants (e.g., Nicotiana varieties) that are suitable for producing therapeutic polypeptides suitable for administration to humans and animals, particularly by making TAL effector endonuclease-induced mutations in genes encoding xylosyltransferases and fucosyltransferases.

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.

In certain embodiments, the present invention provides a poultry vaccine comprising an antigenic protein comprising a PlcC protein unit that is operably linked to a peptide linker that is operably linked to a NetB protein unit, where the vaccine is effective in stimulating a protective cellular and/or humoral immune response to C. perfringens. Methods are also provided for making the vaccine and for vaccinating poultry by administering such a vaccine.

A plant produced vaccine for Porcine Epidemic Diarrhea Virus (PEDV) is provided where the Spike protein of the virus is expressed in a plant by introducing into a plant a construct comprising a promoter preferentially directing expression to seed of said plant, a nucleoic acid encoding the Spike protein and a nucleic acid targeting expression to the endoplasmic reticulum of the plant. The plant expresses the S1 polypeptide at levels of at least 10 mg/kg of seed of said plant. When orally administered to an animal, a protective response is observed including a serum antibody response.

Nucleic acids encoding norovirus VP1 fusion proteins and VLPs comprising the norovirus VP1 fusion proteins are provided. Methods for norovirus VP1 fusion protein and norovirus VLP production in plants are also described. The VP1 fusion protein comprises, a first sequence encoding an S domain derived from a first norovirus strain, and a second sequence encoding a P domain derived from a second norovirus strain.

Materials and methods are provided for making plants (e.g., Nicotiana varieties) that are suitable for producing therapeutic polypeptides suitable for administration to humans and animals, particularly by making TAL effector endonuclease-induced mutations in genes encoding xylosyltransferases and fucosyltransferases.

The present invention relates to a method for increasing the expression and/or promoting correct folding of a heterologous polypeptide of interest in a plant cell, comprising co-expressing the heterologous polypeptide of interest with a polypeptide encoding a mammalian chaperone protein. The invention also relates to plant cells and plants, which either transiently or stably, co-express the heterologous polypeptide of interest and the chaperone protein.

A method of modifying a glycosylation pattern of a polypeptide-of-interest in a plant or plant cell is provided. The method comprising expressing in a plant or plant cell transformed to express at least one glycosidase in a subcellular compartment, a nucleic acid sequence encoding the polypeptide-of-interest, such that the at least one glycosidase and the polypeptide-of-interest are co-localized to the subcellular compartment of the plant or plant cell, thereby modifying the glycosylation pattern of the polypeptide-of-interest in the plant or plant cell.

A plant produced vaccine for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is provided where the Spike protein of the virus is expressed in a plant by introducing into a plant a construct comprising a promoter preferentially directing expression to seed of said plant, a nucleic acid encoding the Spike protein and a nucleic acid targeting expression to the endoplasmic reticulum of the plant. The plant expresses the 51 polypeptide at levels of at least 10 mg/kg of seed of said plant. When orally administered to an animal, a protective response is observed including a serum antibody response.

An antibody is provided that inhibits infection of cells with a norovirus. The antibody is a nanoantibody comprising a polypeptide described in (a), (b), or (c), and inhibiting infection of intestinal cells with HuNoV GII.4: (a) a polypeptide consisting of the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 5, SEQ ID NO: 9, or SEQ ID NO: 13; (b) a polypeptide consisting of an amino acid sequence comprising a substitution, deletion, insertion and/or addition of one or several amino acids with respect to the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 5, SEQ ID NO: 9, or SEQ ID NO: 13; and (c) a polypeptide consisting of an amino acid sequence having a sequence identity of 80% or more to the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 5, SEQ ID NO: 9, or SEQ ID NO: 13.