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Intranasal immunization with plasmid DNA encoding spike protein of SARS-coronavirus/polyethylenimine nanoparticles elicits antigen-specific humoral and cellular immune responses

Byoung-Shik Shim13, Sung-Moo Park23, Ji-Shan Quan14, Dhananjay Jere1, Hyuk Chu5, Man Ki Song3, Dong Wook Kim3, Yong-Suk Jang6, Moon-Sik Yang6, Seung Hyun Han37, Yong-Ho Park2, Chong-Su Cho1 and Cheol-Heui Yun18*

  • * Corresponding author: Cheol-Heui Yun

  • † Equal contributors

Author Affiliations

1 Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea

2 Department of Microbiology, College of Veterinary medicine, Seoul National University, Seoul 151-921, Republic of Korea

3 Laboratory Science Division, International Vaccine Institute, Seoul 151-818, Republic of Korea

4 College of Pharmacy, Yanbian University, Jilin Province 133000, PR China

5 Division of Zoonoses, Center for Immunology & Pathology, National Institute of Health, Korea Center for Disease Control & Prevention, Seoul 122-701, Republic of Korea

6 Division of Biological Sciences and The Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju 561-756, Republic of Korea

7 Department of Oral Microbiology & Immunology, Dental Research Institute, and BK21 Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea

8 Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921, Republic of Korea

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BMC Immunology 2010, 11:65  doi:10.1186/1471-2172-11-65

Published: 31 December 2010



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.


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.


These results showed that intranasal immunization with PEI/pci-S nanoparticles induce antigen specific humoral and cellular immune responses.