Method for producing antibodies in plant cells
AssigneeMonsanto Company
InventorsDavid R. Russell, James T. Fuller
Life of this patent
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Abstract
A method for producing antibodies in plant cells including the steps of providing a genetic construct that encodes a secretable mammalian single chain antibody, delivering copies of the construct into a liquid suspension culture of tobacco cells, selecting for cells that have acquired the genetic construct, allowing the antibody to accumulate in the liquid to a concentration over 25 mg/l and isolating the antibody away from the tobacco cells.
Claims14
A method for obtaining a conformationally active mammalian antibody from plant cells in culture, comprising the steps of:
- providing an expressible DNA construct comprising an expressible selectable marker gene and, in 5' to 3' order, a promoter that promotes transcription in tobacco cells in cell culture, a plant signal sequence that encodes a peptide that directs secretion of a protein from the tobacco cells, a DNA sequence that encodes a secretable mammalian single chain antibody, and a transcription terminator functional in the tobacco cells;
- transforming tobacco suspension cells with the DNA construct;
- selecting for transgenic tobacco cells that have acquired the selectable marker of the DNA construct;
- culturing the transgenic tobacco cells in a liquid suspension culture under conditions such that the cells secrete the mammalian single chain antibody encoded by the DNA construct into the liquid culture to a concentration over 25 mg/l, the accumulated mammalian single chain antibody comprising more than 10% of the total secreted protein in the medium;
- and
- isolating the accumulated single chain mammalian antibody away from the tobacco cells.
A method for preparing a conformationally active single chain mammalian antibody, comprising the steps of:
- transforming NT1 tobacco suspension cells with a DNA construct, the DNA construct comprising an expressible selectable marker gene and, in 5' to 3' order, a Cauliflower Mosaic Virus 35S promoter, a signal sequence selected from the group consisting of a 26 amino acid long signal sequence from a tobacco extensin gene, a 21 amino acid long signal sequence from the tobacco extensin gene, and a signal sequence from a cotton GK12 cDNA clone, a coding region encoding the single chain mammalian antibody, and a transcription terminator functional in the NT1 cells;
- selecting for cells expressing the selectable marker gene;
- culturing the transformed NT1 tobacco cells in a liquid medium under conditions which allow the single chain mammalian antibody encoded by the DNA construct to accumulate in the liquid to a concentration over 25 mg/l, the accumulated mammalian single chain antibody comprising more than 10% of the total secreted protein in the medium;
- and
- isolating the accumulated single chain mammalian antibody away from the NT1 cells.
Dependencies are inferred from the claim text.