title: Immunogenicity of recombinant GP5 protein of porcine reproductive and respiratory syndrome virus expressed in tobacco plant.
abstract: The aim of the study was to evaluate the immunogenicity of the ORF5-encoded major envelop glycoprotein 5 (GP5) of porcine reproductive and respiratory syndrome virus (PRRSV) expressed in tobacco plant as a potential pig oral vaccine in protection against PRRSV infection. Six-week-old PRRSV-free pigs were fed four times orally with 50g of chopped fresh GP5 transgenic tobacco leaves (GP5-T) (GP5 reaching 0.011% of total soluble protein) or wild-type tobacco leaves (W-T) each on days 0, 14, 28, and 42. Samples of serum, saliva, and peripheral blood mononuclear cells (PBMCs) were collected on days -1, 6, 13, 20, 27, 34, 41, and 48 after the initial oral vaccination. A similar vaccination-dependent gradual increase in the responses of serum and saliva anti-PRRSV total IgG and IgA, respectively, and in the levels of PRRSV-specific blastogenic response of PBMCs was seen in GP5-T-treated pigs; all statistically significant elevations occurred after the 2nd vaccination and were revealed after 20 days post-initial oral vaccination (DPIOV). Pigs fed on GP5-T also developed serum neutralizing antibodies to PRRSV at a titer of 1:4-1:8 after the 4th vaccination by 48 DPIOV. No detectable anti-PRRSV antibody responses and PRRSV-specific blastogenic response were seen in W-T-treated pigs. The present study has demonstrated that pigs fed on GP5-T could develop specific mucosal as well as systemic humoral and cellular immune responses against PRRSV. The results also support that transgenic plant as GP5-T can be an effective system for oral delivery of recombinant subunit vaccines in pigs.
authors.affiliation: Graduate Institute of Veterinary Medicine, School of Veterinary Medicine, Taipei 106, Taiwan, ROC.
authors.forename: Min-Yuan
authors.initials: MY
authors.lastname: Chia
authors.forename: Shih-Hsuan
authors.initials: SH
authors.lastname: Hsiao
authors.forename: Hui-Ting
authors.initials: HT
authors.lastname: Chan
authors.forename: Yi-Yin
authors.initials: YY
authors.lastname: Do
authors.forename: Pung-Ling
authors.initials: PL
authors.lastname: Huang
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Chang
authors.forename: Yi-Chieh
authors.initials: YC
authors.lastname: Tsai
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Lin
authors.forename: Victor Fei
authors.initials: VF
authors.lastname: Pang
authors.forename: Chian-Ren
authors.initials: CR
authors.lastname: Jeng
mesh_terms: D000284:Administration, Oral; D000818:Animals; D057134:Antibodies, Neutralizing / Q000096:biosynthesis / Q000097:blood; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood; D001483:Base Sequence; D019149:Bioreactors; D004279:DNA, Viral / Q000235:genetics; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D018928:Immunity, Mucosal; D007071:Immunoglobulin A, Secretory / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood; D008213:Lymphocyte Activation; D008297:Male; D030821:Plants, Genetically Modified; D019318:Porcine Reproductive and Respiratory Syndrome / Q000276:immunology / Q000517:prevention & control; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics* / Q000276:immunology*; D012463:Saliva / Q000276:immunology; D034421:Sus scrofa; D013552:Swine; D014026:Nicotiana / Q000235:genetics*; D022462:Vaccines, Edible / Q000008:administration & dosage / Q000235:genetics; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000235:genetics*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004279:DNA, Viral; D007071:Immunoglobulin A, Secretory; D007074:Immunoglobulin G; D022462:Vaccines, Edible; D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C114789:glycoprotein 5, PRRSV