Tobacco NT-1 or BY-2 (Bright Yellow-2) cell lines in suspension are incubated with Agrobacterium tumefaciens containing a plasmid with the genes for the autoantigen and a selective agent such as an herbicide (Bialaphos) or antibiotic. Then, the cell suspension is placed on a plate containing a selective media, and resistant calli are regenerated in 10-14 days. A callus consists of an actively dividing non-organized mass of undifferentiated cell tissue induced by hormones. Elite callus lines expressing the highest levels of antigen are selected and resuspended in liquid media to obtain a transgenic NT1 or BY-2 cell culture, which is freeze-dried, pulverized and made into capsules for oral vaccination.
