• IMMUNE NETWORK
• /
• v.9 no.5
• /
• pp.169-178
• /
• 2009

DNA immunization induces B and T cell responses to various pathogens and tumors. However, these responses are known to be relatively weak and often transient. Thus, novel strategies are necessary for enhancing immune responses induced by DNA immunization. Here, we demonstrated that co-immunization of influenza virus nucleoprotein (NP) gene significantly enhances humoral and cell-mediated responses to codelivered antigens in mice. We also found that NP DNA coimmunization augments in vivo proliferation of adoptively transferred antigen-specific CD4 and CD8 T cells, which enhanced protective immunity against tumor challenge. Our results suggest that NP DNA can serve as a novel genetic adjuvant in cocktail DNA vaccination.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2002.11b
• /
• pp.157-157
• /
• 2002

The toxicity of GX-12, a naked DNA vaccine developed by research team of Dong-A Pharmaceutical Company, Green Cross Company and Genexine for the treatment of HIV infection, was investigated in Sprague-Dawley rats. In single-dose intramuscular/oral acute toxicity studies, animals were treated 0, 250, 1000 or 4000 $\mu\textrm{g}$/kg/$m\ell$ in sodium phosphate buffer.(omitted)

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2002.11b
• /
• pp.201-201
• /
• 2002

GX-12 is a naked DNA vaccine developed by Dong-A pharmaceutical company for the treatment of mv infection. GX-12 consists of four separate plasmids. This study was performed to evaluate the biodistribution and expression of GX-12 mRNA in gonadal tissues, and to investigate the histopathological changes in rats after repeated intramuscular injection.(omitted)

• Korean Journal of Veterinary Research
• /
• v.32 no.4
• /
• pp.597-603
• /
• 1992

To elucidate the molecular genetical properties of the canine parvoviruses isolated from the diseased puppies in the regions of Kyunggi and Chungnam provinces, the replicative form (RF) DNA of four field isolates were compared with those of two attenuated vaccine strains and a reference strains of CPV by restriction endonuclease analysis (REA). REA by Hinf I showed that three CPV isolates except CPV-V15 had an identical banding pattern with two vaccine strains, one standard strain and feline panleukopenia virus (FPLV). In CPV-V15 strain the fourth fragment of DNA with 800 bp was deleted. REA by Bgl II and Pst I indicated that CPV-V15 and FPLV had a bigger second fragment than those of the other strains of CPV. Meanwhile REA by Bam HI revealed that all the field isolates and vaccine strains used in this experiment showed similar banding patterns.

• Archives of Pharmacal Research
• /
• v.26 no.6
• /
• pp.493-498
• /
• 2003

In this study we have investigated the pharmacokinetics and tissue distribution of GX-12, a multiple plasmid DNA vaccine for the treatment of HIV-1 infection. Plasmid DNA was rapidly degraded in blood with a half-life of 1.34 min and was no longer detectable at 90 min after intravenous injection in mice. After intramuscular injection, plasmid DNA concentration in the injection site rapidly declined to less than 1 ％ of the initial concentration by 90 min post-injection. However, sub-picogram levels (per mg tissue) were occasionally detected for several days after injection. The relative proportions of the individual plasm ids of GX-12 remained relatively constant at the injection site until 90 min post-injection. The concentration of plasmid DNA in tissues other than the injection site peaked at 90 min post-injection and decreased to undetectable levels at 8 h post-injection. The rapid in vivo degradation of GX-12 and absence of persistence in non-target tissues suggest that the risk of potential gene-related toxicities by GX-12 administration, such as expression in non-target tissues, insertional mutagenesis and germline transmission, is minimal.

• BMB Reports
• /
• v.31 no.5
• /
• pp.432-443
• /
• 1998

The poliovirus Sabin 1 strain has features that make it a particularly attractive live recombinant mucosal vaccine vehicle. Sabin 1 cDNA was manipulated to have multiple cloning sites and a viral specific 3C-protease cutting site at the N-terminal end of the polyprotein. The gene for the N-terminal 169 amino acids of the HIV-1 p24 was cloned into the multiple cloning site of the manipulated Sabin cDNA. A recombinant progeny virus was produced from HeLa cells when it was transfected with the RNA synthesized from the p24-Sabin chimeric cDNA. The recombinant progeny virus expresses substantial amounts of the HIV-1 p24 protein, which was clearly detected in the infected cell lysates and culture supernatants in Western blot experiments with rabbit anti-p24 serum and AIDS patients' sera. Differing from the Mahoney strain, the recombinant Sabin 1 poliovirus maintained the foreign gene stably during the subsequent passages. Replication capacity was about 1 to 1.5 log lower than that of the wild-type Sabin 1. Other physicochemical stability characteristics of the recombinant virus were similar to that of the wild-type Sabin 1. These results suggest that the manipulated Sabin 1 poliovirus can be used as a live viral vaccine vector for the development of mucosal vaccines.

• Journal of the korean veterinary medical association
• /
• v.46 no.12
• /
• pp.1100-1105
• /
• 2010

• Journal of the korean veterinary medical association
• /
• v.47 no.1
• /
• pp.67-80
• /
• 2011

• Parasites, Hosts and Diseases
• /
• v.49 no.1
• /
• pp.85-90
• /
• 2011

Relatively little has been studied on the AMA-1 vaccine against Plasmodium vivax and on the plasmid DNA vaccine encoding P. vivax AMA-1 (PvAMA-1). In the present study, a plasmid DNA vaccine encoding AMA-1 of the reemerging Korean P. vivax has been constructed and a preliminary study was done on its cellular immunogenicity to recipient BALB/c mice. The PvAMA-1 gene was cloned and expressed in the plasmid vector UBpcAMA-1, and a protein band of approximately 56.8 kDa was obtained from the transfected COS7 cells. BALB/c mice were immunized intramuscularly or using a gene gun 4 times with the vaccine, and the proportions of splenic T-cell subsets were examined by fluorocytometry at week 2 after the last injection. The spleen cells from intramuscularly injected mice revealed no significant changes in the proportions of CD8$^+$ T-cells and CD4$^+$ T-cells. However, in mice immunized using a gene gun, significantly higher (P<0.05) proportions of CD8$^+$ cells were observed compared to UB vector-injected control mice. The results indicated that cellular immunogenicity of the plasmid DNA vaccine encoding AMA-1 of the reemerging Korean P. vivax was weak when it was injected intramuscularly; however, a promising effect was observed using the gene gun injection technique.

• IMMUNE NETWORK
• /
• v.11 no.5
• /
• pp.268-280
• /
• 2011

Background: Dengue virus, which belongs to the Flavivirus genus of the Flaviviridae family, causes fatal dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) with infection risk of 2.5 billion people worldwide. However, approved vaccines are still not available. Here, we explored the immune responses induced by alternating prime-boost vaccination using DNA vaccine, adenovirus, and vaccinia virus expressing E protein of dengue virus type 2 (DenV2). Methods: Following immunization with DNA vaccine (pDE), adenovirus (rAd-E), and/or vaccinia virus (VV-E) expressing E protein, E protein-specific IgG and its isotypes were determined by conventional ELISA. Intracellular CD154 and cytokine staining was used for enumerating CD4+ T cells specific for E protein. E protein-specific CD8+ T cell responses were evaluated by in vivo CTL killing activity and intracellular IFN-${\gamma}$ staining. Results: Among three constructs, VV-E induced the most potent IgG responses, Th1-type cytokine production by stimulated CD4+ T cells, and the CD8+ T cell response. Furthermore, when the three constructs were used for alternating prime-boost vaccination, the results revealed a different pattern of CD4+ and CD8+ T cell responses. i) Priming with VV-E induced higher E-specific IgG level but it was decreased rapidly. ii) Strong CD8+ T cell responses specific for E protein were induced when VV-E was used for the priming step, and such CD8+ T cell responses were significantly boosted with pDE. iii) Priming with rAd-E induced stronger CD4+ T cell responses which subsequently boosted with pDE to a greater extent than VV-E and rAd-E. Conclusion: These results indicate that priming with live viral vector vaccines could induce different patterns of E protein-specific CD4+ and CD8+ T cell responses which were significantly enhanced by booster vaccination with the DNA vaccine. Therefore, our observation will provide valuable information for the establishment of optimal prime-boost vaccination against DenV.