Expression in plants and immunogenicity of a fusion protein containing an epitope from the swine transmissible gastroenteritis virus S protein

by Bailey, Andrea Elizabeth

EXPRESSION IN PLANTS AND IMMUNOGENICEY OF A FUSION PROTEIN CONTAINING AN EPITOPE FROM THE SWINE TRANSMISSIBLE GASTROENTERrrIS VIRUS S PROTEIN Andrea Elizabeth Baiiey University of Guelph, 2000 Advisor: Dr. L-R- Erickson One interesting possibility offered by recent advances in plant biotechnology is the production of antigens in plants for use as oraliy administered vaccines. Ln this work, a subunit vaccine was designed for production in transgenic aifalfa. A genetic consû-uct encoding a fusion protein containing a neutralizing epitope from the transmissible gastroenteritis virus (TGEV) was generated and introduced into tobacco and aifalfa. The fusion partner was a portion of the pollen-specific alfalfa protein P02. This P02-D protein was detected in plants using antibodies to P02, and was found to be more extensively glycosylated in alfalfa leaves than in tobacco leaves. However, as both the aifalfa and tobacco plants matured, the expression of P02-D diminished. To determine the imrnunogenicity of P02-D, crude protein extracts from transgenic leaf tissue were injected intraperitoneally (i-p.) into mice and the semm antibodies exarnined for reactivity with TGEV. Both TGEV-specific and TGEV neutralizing antibodies were detected.