Abstract: The present invention relates to expression and assembly of foreign multimeric proteins—e.g., antibodies—in plants, as well as to transgenic plants that express such proteins. In one of several preferred embodiments, the generation and assembly of functional secretory antibodies in plants is disclosed. The invention also discloses compositions produced by the transgenic plants of the present invention and methods of using same.

Abstract: Polypeptide targeting molecules are provided for use in delivering imaging agents to epithelial tissue. Upon delivery, the imaging agent(s) may remain within an epithelial cell or may undergo transepithelial transport via transcytosis. The targeting molecules may be used, for example, for diagnostic techniques. The polypeptide may be produced by recombinant methods, and forms a closed covalent loop, contains at least three peptide domains having &bgr;-sheet character which are separated by domains lacking &bgr;-sheet character, specifically binds to a basolateral factor attached to a basolateral domain of an epithelial surface causing uptake of a linked imaging agent into cells of the epithelial surface, and is not a full length dimeric Iga. Preferably, the polypeptide is a J chain polypeptide, or a J chain polypeptide linked to an immunoglobulin heavy chain without an immunoglobulin light chain.

Abstract: Targeting molecules for use in delivering biological agents to non-polarized epithelial cells are disclosed. Upon delivery, the biological agent(s) are lethal to the epithelial cell. The targeting molecules may be used, for example, for the eradication of metastatic epithelial cells.

Abstract: Targeting molecules for use in delivering imaging agents to epithelial tissue are disclosed. Upon delivery, the imaging agent(s) may remain within an epithelial cell or may undergo transepithelial transport via transcytosis. The targeting molecules may be used, for example, for diagnostic techniques. The targeting molecule is a polypeptide, which may be produced by recombinant methods, that forms a closed covalent loop, contains at least three peptide domains having .beta.-sheet character which are separated by domains lacking .beta.-sheet character, specifically binds to a basolateral factor attached to a basolateral domain of an epithelial surface causing uptake of a linked imaging agent into cells of the epithelial surface, and is not a full length dimeric Iga. Preferably, the polypeptide is a J chain polypeptide, or a J chain polypeptide linked to an immunoglobulin heavy chain without an immunoglobulin light chain.

Abstract: The present invention relates to expression and assembly of foreign multimeric proteins--e.g., antibodies--in plants, as well as to transgenic plants that express such proteins. In one of several preferred embodiments, the generation and assembly of functional secretory antibodies in plants is disclosed. The invention also discloses compositions produced by the transgenic plants of the present invention and methods of using same.

Abstract: The present invention contemplates a transgenic plant having somatic and germ cells containing at least two mammalian genes coding for polypeptides capable of autogenously associating with each other to form a biologically active multimer. In addition, the invention describes a method for producing a glycopolypeptide multimer by introducing first and second mammalian genes encoding the constituent parts of the multimer into first and second respective members of a plant species, generating a progeny from the first and second plant species members, and isolating the glycopolypeptide multimer from the progeny plant.

Abstract: The present invention contemplates glycopolypeptide multimers having a polypeptide that contain an immunoglobulin amino acid residue sequence and an oligosaccharide that comprises a core pentasaccharide and N-acetylglucosamine-containing outer branches, such that the multimer is free from sialic acid. The production of passive immunity in an animal by administering a sialic acid free glycopolypeptide multimer is also contemplated. In addition, the invention describes a method for producing a glycopolypeptide multimer by introducing first and second mammalian genes encoding the constituent parts of the multimer into first and second respective members of a plant species, generating a progeny from the first and second plant species members, and isolating the glycopolypeptide multimer from the progeny plant.