The relative immunogenicity of DNA vaccines delivered by the intramuscular needle injection, electroporation and gene gun methods

China-US Vaccine Research Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
Vaccine (Impact Factor: 3.62). 05/2008; 26(17):2100-10. DOI: 10.1016/j.vaccine.2008.02.033
Source: PubMed


Immunogenicity of DNA vaccines varies significantly due to many factors including the inherent immunogenicity of the protein antigen encoded in the DNA vaccine, the optimal immune responses that can be achieved in different animal models and in humans with different genetic backgrounds and, to a great degree, the delivery methods used to administer the DNA vaccines. Based on published results, only the gene gun-mediated delivery approach has been able to elicit protective levels of immune responses in healthy, adult volunteers by DNA immunization alone without the use of another vaccine modality as a boost. Recent results from animal studies suggest that electroporation is also effective in eliciting high level immune responses. However, there have been no reports to identify the similarities and differences between these two leading physical delivery methods for DNA vaccines against infectious disease targets. In the current study, we compared the relative immunogenicity of a DNA vaccine expressing a hemagglutinin (HA) antigen from an H5N1 influenza virus in two animal models (rabbit and mouse) when delivered by either intramuscular needle immunization (IM), gene gun (GG) or electroporation (EP). HA-specific antibody, T cell and B cell responses were analyzed. Our results indicate that, overall, both the GG and EP methods are more immunogenic than the IM method. However, EP and IM stimulated a Th-1 type antibody response and the antibody response to GG was Th-2 dominated. These findings provide important information for the further selection and optimization of DNA vaccine delivery methods for human applications.


Available from: Shan Lu
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    • "However, on their own DNA plasmid vaccines have exhibited very limited immunostimulatory capacity and often induced suboptimal immune responses. Recent advances in DNA delivery such as intramuscular, skin or intradermal electroporation (Selby et al., 2000; Widera et al., 2000; Brave et al., 2010; Vasan et al., 2011; Kopycinski et al., 2012) or use of other physical delivery methods such as gene gun and biojector devices (Drape et al., 2006; Wang et al., 2008a; Graham et al., 2013), together with concurrent use of cytokine adjuvants including IL-2, IL- 12, and IL-15 (Winstone et al., 2011; Kalams et al., 2012, 2013) have greatly improved the immunogenic potential of DNA vaccines . In particular, IL-12 was shown to significantly augment the frequency, magnitude and breadth of Gag-specific immune responses in healthy volunteers immunized with a recombinant DNA vaccine expressing HIV-1 Gag (Kalams et al., 2012, 2013). "
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    Frontiers in Microbiology 08/2014; 5(439):439. DOI:10.3389/fmicb.2014.00439 · 3.99 Impact Factor
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    • "The relative immunogenicity of DNA vaccines expressing HBs-L and HBs-L(T) were examined in Balb/C mice by electroporation as previous described [34]. The same amount of DNA vaccine expressing either HBs-L or HBs-L(T) was administered individually to mice at Weeks 0, 2, and 4. Compared to the HBs-L DNA vaccine, the HBs-L(T) DNA vaccine induced HBsAg-specific antibody responses earlier and with higher titers (Fig 2). "
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    • "Although the mechanism underlying which is unclear, we think the HA may play roles in this discrepancy between the results of Heinen et al.’s and ours. Another possible reason should be taken into consideration is that gene gun immunization induces more strong immune response that the conventional needle injection method, which was used in Heinen et al.’s study [37]. It is necessary to study whether the DNA vaccines we developed here will confer protection in pig models. "
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