Human respiratory syncytial virus vaccine antigen produced in plants

Human respiratory syncytial virus (RSV) is the primary cause of respiratory infection in infants worldwide. Currently there is no available vaccine, a lthough studies in animal models have demonstrated protective immunity indu ced by an epitope of the RSV G-protein representing amino acids 174-187. Tw o peptides containing amino acids 174-187 of the G-protein of the human RSV A2 strain (NF1-RSV/172-187 and NF2-RSV/170-191) were separately engineered as translational fusions with the alfalfa mosaic virus coat protein and in dividually expressed in Nicotiana tabacum cv. Samsun NN plants through viru s infection. RSV G-protein peptides were expressed in infected plant tissue s at significant levels within 2 wk of inoculation and purified as part of recombinant alfalfa mosaic virions. BALB/c mice immunized intraperitoneally with three doses of the purified recombinant viruses showed high levels of serum antibody specific for RSV G-protein and were protected against infec tion with RSV Long strain.-Belanger, H., Fleysh, N., Cox, S., Bartman, G., Deka, D., Trudel, M., Koprowski, H., Yusibov, V. Human respiratory syncytia l virus vaccine antigen produced in plants.