title: Intranasal immunization with plasmid DNA encoding spike protein of SARS-coronavirus/polyethylenimine nanoparticles elicits antigen-specific humoral and cellular immune responses.
abstract: BACKGROUND
  Immunization with the spike protein (S) of severe acute respiratory syndrome (SARS)-coronavirus (CoV) in mice is known to produce neutralizing antibodies and to prevent the infection caused by SARS-CoV. Polyethylenimine 25K (PEI) is a cationic polymer which effectively delivers the plasmid DNA.
  
  
  RESULTS
  In the present study, the immune responses of BALB/c mice immunized via intranasal (i.n.) route with SARS DNA vaccine (pci-S) in a PEI/pci-S complex form have been examined. The size of the PEI/pci-S nanoparticles appeared to be around 194.7 ± 99.3 nm, and the expression of the S mRNA and protein was confirmed in vitro. The mice immunized with i.n. PEI/pci-S nanoparticles produced significantly (P < 0.05) higher S-specific IgG1 in the sera and mucosal secretory IgA in the lung wash than those in mice treated with pci-S alone. Compared to those in mice challenged with pci-S alone, the number of B220+ cells found in PEI/pci-S vaccinated mice was elevated. Co-stimulatory molecules (CD80 and CD86) and class II major histocompatibility complex molecules (I-Ad) were increased on CD11c+ dendritic cells in cervical lymph node from the mice after PEI/pci-S vaccination. The percentage of IFN-γ-, TNF-α- and IL-2-producing cells were higher in PEI/pci-S vaccinated mice than in control mice.
  
  
  CONCLUSIONS
  These results showed that intranasal immunization with PEI/pci-S nanoparticles induce antigen specific humoral and cellular immune responses.
authors.affiliation: Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Byoung-Shik
authors.initials: BS
authors.lastname: Shim
authors.forename: Sung-Moo
authors.initials: SM
authors.lastname: Park
authors.forename: Ji-Shan
authors.initials: JS
authors.lastname: Quan
authors.forename: Dhananjay
authors.initials: D
authors.lastname: Jere
authors.forename: Hyuk
authors.initials: H
authors.lastname: Chu
authors.forename: Man Ki
authors.initials: MK
authors.lastname: Song
authors.forename: Dong Wook
authors.initials: DW
authors.lastname: Kim
authors.forename: Yong-Suk
authors.initials: YS
authors.lastname: Jang
authors.forename: Moon-Sik
authors.initials: MS
authors.lastname: Yang
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Han
authors.forename: Yong-Ho
authors.initials: YH
authors.lastname: Park
authors.forename: Chong-Su
authors.initials: CS
authors.lastname: Cho
authors.forename: Cheol-Heui
authors.initials: CH
authors.lastname: Yun
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D000917:Antibody Formation / Q000187:drug effects; D000954:Antigens, Surface / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000821:virology; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004247:DNA / Q000008:administration & dosage / Q000276:immunology*; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000821:virology; D000939:Epitopes / Q000276:immunology; D007109:Immunity / Q000187:drug effects / Q000276:immunology*; D007111:Immunity, Cellular / Q000187:drug effects / Q000276:immunology; D056724:Immunity, Humoral / Q000187:drug effects / Q000276:immunology; D007114:Immunization / Q000379:methods*; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D053758:Nanoparticles / Q000737:chemistry*; D010957:Plasmids / Q000008:administration & dosage / Q000276:immunology*; D011094:Polyethyleneimine / Q000494:pharmacology*; D064370:Spike Glycoprotein, Coronavirus; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000821:virology; D014759:Viral Envelope Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000954:Antigens, Surface; D000939:Epitopes; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; C578557:spike glycoprotein, SARS-CoV; D011094:Polyethyleneimine; D004247:DNA