Genetic immunization with Hantavirus vaccine combining expression of G2 glycoprotein and fused interleukin-2 Huang Hao1,3, Li Xiu2, Zhang Zehua1, Jia Min1, Hu Hongbo1, Wu Zhihong1, Zhu Zhenhua1, Wan Xiaohong1 and Huang Hanju*1

In this research, we developed a novel chimeric HTNV-IL-2-G2 DNA vaccine plasmid by genetically linking IL-2 gene to the G2 segment DNA and tested whether it could be a candidate vaccine. Chimeric gene was first expressed in eukaryotic expression system pcDNA3.1 (+). The HTNV-IL2-G2 expressed a 72 kDa fusion protein in COS-7 cells. Meanwhile, the fusion protein kept the activity of its parental proteins. Furthermore, BALB/c mice were vaccinated by the chimeric gene. ELISA, cell microculture neutralization test in vitro were used to detect the humoral immune response in immunized BALB/c mice. Lymphocyte proliferation assay was used to detect the cellular immune response.The results showed that the chimeric gene could simultaneously evoke specific antibody against G2 glycoprotein and IL-2. And the immunized mice of every group elicited neutralizing antibodies with different titers. Lymphocyte proliferation assay results showed that the stimulation indexes of splenocytes of chimeric gene to G2 and IL-2 were significantly higher than that of other groups. Our results suggest that IL-2-based HTNV G2 DNA can induce both humoral and cellular immune response specific for HTNV G2 and can be a candidate DNA vaccine for HTNV infection. Introduction The Hantaan virus (HTNV) is a member of the genus Hantavirus of the family Bunyaviridae and a causative agent of hemorrhagic fever with renal syndrome (HFRS) [1,2]. More than 100,000 cases of HFRS are reported annually, with a mortality rate between 2% and 10% [3]. However, no effective vaccine has been developed to prevent this disease. HTNV is a spherical, enveloped virus with a genome consisting of three segments of single-stranded, negativesense RNA. The three segments are designated as large (L), medium (M), and small (S) segments that encode RNAdependent RNA polymerase, respectively [4]]. It is indicated that the glycoprotein (GP), which was encoded by M segment, could elicit organism to produce neutralizing antibody and could protect infected animal and human Published: 22 October 2008 Genetic Vaccines and Therapy 2008, 6:15 doi:10.1186/1479-0556-6-15 Received: 29 May 2008 Accepted: 22 October 2008 This article is available from: http://www.gvt-journal.com/content/6/1/15 © 2008 Hao et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.