Therapeutic HIV vaccine was considered as a hopeful curative method for AIDS patients. However, there is still no suitable HIV animal model for vaccine study since the difference in the immune system between human and animals. To evaluate the therapeutic effect of combined immunization strategy with multiple vector vaccines in macaque models. Plasmid DNA, recombinant Ad5 and MVA vaccines which expressing SIV gag and env genes were constructed. Sequential and repeated immune strategy were applied to immunize mice with these three vaccines. Cellular immune responses in mice immunized with these three vaccines were measured by ELISPOT test in vitro and CTL assay in vivo. The results were analyzed and compared with different antigen combination, order of vaccines and intervals to choose a suitable immunization strategy for macaque immunization in future. It indicated that strong SIV-Gag/Env-specific cellular immune responses were induced by these three vector vaccines. It laid a foundation for evaluating the therapeutic effect of combined immunization strategy with multiple vector vaccines in SIV infected macaque models.
AIDS Vaccines ; administration & dosage ; genetics ; immunology ; Adenoviridae ; genetics ; metabolism ; Animals ; Antibodies, Viral ; immunology ; Female ; Gene Products, env ; administration & dosage ; genetics ; immunology ; Gene Products, gag ; administration & dosage ; genetics ; immunology ; Genetic Vectors ; genetics ; metabolism ; HIV Infections ; immunology ; prevention & control ; virology ; Humans ; Immunization ; Mice ; Mice, Inbred BALB C ; Simian Immunodeficiency Virus ; genetics ; immunology ; Vaccines, DNA ; administration & dosage ; genetics ; immunology

To optimize the immunization strategy against HIV-1, a DNA vaccine was combined with a recombinant vaccinia virus (rTV) vaccine and a protein vaccine. Immune responses against HIV-1 were detected in 30 female guinea pigs divided into six groups. Three groups of guinea pigs were primed with HIV-1 DNA vaccine three times, boosted with rTV at week 14, and then boosted with gp140 protein at intervals of 4, 8 or 12 weeks. Simultaneously, the other three groups of animals were primed with rTV vaccine once, and then boosted with gp140 after 4, 8 or 12 weeks. The HIV-1 specific binding antibody and neutralizing antibody, in addition to the relative affinity of these antibodies, were detected at different time points after the final administration of vaccine in each group. The DNA-rTV-gp140 immune regimen induced higher titers and affinity levels of HIV-1 gp120/gp140 antibodies and stronger V1V2-gp70 antibodies than the rTV-gp140 regimen. In the guinea pigs that underwent the DNA-rTV-gp140 regimen, the highest V1V2-gp70 antibody was induced in the 12-week-interval group. However, the avidity of antibodies was improved in the 4-week-interval group. Using the rTV-gp140 immunization strategy, guinea pigs boosted at 8 or 12 weeks after rTV priming elicited stronger humoral responses than those boosted at 4 weeks after priming. In conclusion, this study shows that the immunization strategy of HIV-1 DNA vaccine priming, followed by rTV and protein vaccine boosting, could strengthen the humoral response against HIV-1. Longer intervals were better to induce V1V2-gp70-specific antibodies, while shorter intervals were more beneficial to enhance the avidity of antibodies.
AIDS Vaccines ; administration & dosage ; genetics ; immunology ; Animals ; DNA, Viral ; administration & dosage ; genetics ; immunology ; Female ; Guinea Pigs ; HIV Infections ; immunology ; prevention & control ; virology ; HIV-1 ; genetics ; immunology ; Humans ; Immunization ; methods ; Vaccines, DNA ; administration & dosage ; genetics ; immunology ; Vaccinia virus ; genetics ; immunology ; env Gene Products, Human Immunodeficiency Virus ; administration & dosage ; genetics ; immunology

This study aimed to investigate the immune adjuvant effect and mechanism induced by chitosan nanoparticles carrying pJME/GM-CSF. In this study, plasmid DNA (pJME/GM-CSF) was encapsulated in chitosan to prepare chitosan-pJME/GM-CSF nanoparticles using a complex coacervation process. Immunohistochemistry was used to detect the type of infiltrating cells at the site of intramuscular injection. The phenotype and functional changes of splenic DCs were measured by flow cytometry after different immunogens were injected intramuscularly. The killing activity of CTLs was assessed using the lactate dehydrogenase (LDH) release assay. The preparation of chitosan-pJME/GM-CSF nanoparticles matched the expected theoretical results. Our results also found that, after pJME/GM-CSF injection, the incoming cells were a mixture of macrophages, neutrophils, and immature DCs. Meanwhile, pJME/GM-CSF increased the expression of MHC class II molecules on splenic DCs, and enhanced their Ag capture and presentation functions. Cell-mediated immunity was induced by the vaccine. Furthermore, chitosan-pJME/GM-CSF nanoparticles outperformed the administration of standard pJME/GM-CSF in terms of DC recruitment, antigen processing and presentation, and vaccine enhancement. These findings reveal that chitosan could be used as delivery vector for DNA vaccine intramuscular immunizations, and enhance pJME/GM-CSF-induced cellular immune responses.
Adjuvants, Immunologic ; administration & dosage ; Animals ; Chitosan ; administration & dosage ; immunology ; Dendritic Cells ; immunology ; virology ; Encephalitis Virus, Japanese ; genetics ; immunology ; Encephalitis, Japanese ; immunology ; prevention & control ; virology ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; administration & dosage ; genetics ; immunology ; Humans ; Immunity, Cellular ; Japanese Encephalitis Vaccines ; administration & dosage ; genetics ; immunology ; Mice ; Mice, Inbred BALB C ; Nanoparticles ; administration & dosage ; Spleen ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; virology ; Vaccines, DNA ; administration & dosage ; genetics ; immunology

This study aimed to evaluate the efficacy of fructose-1,6-bis phosphate aldolase (SMALDO) DNA vaccination against Schistosoma mansoni infection using different routes of injection. The SMALDO has been cloned into the eukaryotic expression vector pcDNA3.1/V5-His TOPO-TA and was used in injecting Swiss albino mice intramuscularly (IM), subcutaneously (SC), or intraperitoneally (IP) (50 microg/mouse). Mice vaccinated with non-recombinant pcDNA3.1 served as controls. Each group was immunized 4 times at weeks 0, 2, 4, and 6. Two weeks after the last booster dose, all mice groups were infected with 80 S. mansoni cercariae via tail immersion. At week 8 post-infection, animals were sacrificed for assessment of parasitological and histopathological parameters. High anti-SMALDO IgG antibody titers were detected in sera of all vaccinated groups (P<0.01) compared to the control group. Both the IP and SC vaccination routes resulted in a significant reduction in worm burden (46.2% and 28.9%, respectively, P<0.01). This was accompanied by a significant reduction in hepatic and intestinal egg counts (41.7% and 40.2%, respectively, P<0.01) in the IP group only. The number of dead eggs was significantly increased in both IP and IM groups (P<0.01). IP vaccination recorded the highest significant reduction in granuloma number and diameter (54.7% and 29.2%, respectively, P<0.01) and significant increase in dead miracidia (P<0.01). In conclusion, changing the injection route of SMALDO DNA vaccination significantly influenced the efficacy of vaccination. SMALDO DNA vaccination via IP route could be a promising protective and anti-pathology vaccine candidate against S. mansoni infection.
Animals ; Antibodies, Helminth/blood ; Disease Models, Animal ; Female ; Fructose-Bisphosphate Aldolase/genetics/*immunology ; Histocytochemistry ; Immunoglobulin G/blood ; Injections, Intramuscular ; Injections, Intraperitoneal ; Injections, Subcutaneous ; Mice ; Parasite Load ; Schistosoma mansoni/enzymology/genetics/*immunology ; Schistosomiasis mansoni/immunology/parasitology/pathology/*prevention & control ; Vaccination/methods ; Vaccines, DNA/administration & dosage/genetics/*immunology ; Vaccines, Synthetic/administration & dosage/genetics/immunology

To control coccidiosis without using prophylactic medications, a DNA vaccine targeting the gametophyte antigen Gam56 from Eimeria maxima in chickens was constructed, and the immunogenicity and protective effects were evaluated. The ORF of Gam56 gene was cloned into an eukaryotic expression vector pcDNA3.1(zeo)+. Expression of Gam56 protein in COS-7 cells transfected with recombinant plasmid pcDNA-Gam56 was confirmed by indirect immunofluorescence assay. The DNA vaccine was injected intramuscularly to yellow feathered broilers of 1-week old at 3 dosages (25, 50, and 100 microg/chick). Injection was repeated once 1 week later. One week after the second injection, birds were challenged orally with 5x10(4) sporulated oocysts of E. maxima, then weighed and killed at day 8 post challenge. Blood samples were collected and examined for specific peripheral blood lymphocyte proliferation activity and serum antibody levels. Compared with control groups, the administration of pcDNA-Gam56 vaccine markedly increased the lymphocyte proliferation activity (P<0.05) at day 7 and 14 after the first immunization. The level of lymphocyte proliferation started to decrease on day 21 after the first immunization. A similar trend was seen in specific antibody levels. Among the 3 pcDNA-Gam56 immunized groups, the median dosage group displayed the highest lymphocyte proliferation and antibody levels (P<0.05). The median dosage group had the greatest relative body weight gain (89.7%), and the greatest oocyst shedding reduction (53.7%). These results indicate that median dosage of DNA vaccine had good immunogenicity and immune protection effects, and may be used in field applications for coccidiosis control.
Animals ; Antibodies, Protozoan/blood ; Antigens, Protozoan/genetics/*immunology ; Cell Proliferation ; Chickens ; Coccidiosis/immunology/pathology/*prevention & control ; Disease Models, Animal ; Eimeria/genetics/*immunology ; Injections, Intramuscular ; Lymphocytes/immunology ; Protozoan Vaccines/administration & dosage/genetics/*immunology ; Vaccination/methods ; Vaccines, DNA/administration & dosage/genetics/*immunology

This paper is aimed to investigate the transcription and expression of BCR-ABL-pIRES-SEA fusion gene vaccines in vivo in mice. The reconstructed plasmids (BCR-ABL-pIRES-SEA) which were developed previously in our laboratory were injected into the skeletal muscles of BALB/c mice at 14d intervals for three cycles. The transcription and expression of BCR-ABL and staphylococcal enterotoxin A (SEA) in injection site were detected using RT-PCR and immunohistological methods. The BCR-ABL/SEA mRNA and protein could be identified in the injection site of BCR-ABL-pIRES-SEA vaccinated mice. The reconstructed BCR-ABL-pIRES-SEA plasmids can effectively express gene production in the skeletal muscles of mice and have the common features of DNA vaccine.
Animals ; Enterotoxins ; genetics ; immunology ; metabolism ; Fusion Proteins, bcr-abl ; genetics ; immunology ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Muscle, Skeletal ; metabolism ; Plasmids ; immunology ; RNA, Messenger ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Vaccines, DNA ; administration & dosage ; immunology

To investigate the adjuvant effect of granulocyte macrophage colony stimulating factor (GM-CSF) in Flaviviridae virus DNA vaccines. After DNA immunization, the antibody levels of serum from mice were detected by ELISA and indirect immunofluorescence assay. Co-immunization of GM-CSF suppressed the immune responses induced by DV1 and DV2 candidate vaccines whereas enhanced the immune response induced by HCV C and E1 DNA vaccines. As genetic adjuvant for DNA vaccines, GM-CSF might display complex diversity on the immune responses: an augmentation or suppression due to different immunogens. Therefore, GM-CSF should be used with some cautions in clinic.
Adjuvants, Immunologic ; administration & dosage ; Animals ; Antibodies, Viral ; immunology ; DNA, Viral ; administration & dosage ; genetics ; immunology ; Dengue ; immunology ; prevention & control ; virology ; Dengue Vaccines ; administration & dosage ; genetics ; immunology ; Dengue Virus ; genetics ; immunology ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; administration & dosage ; immunology ; Hepacivirus ; genetics ; immunology ; Hepatitis C ; immunology ; prevention & control ; virology ; Humans ; Immunization ; Mice ; Mice, Inbred BALB C ; Vaccines, DNA ; administration & dosage ; genetics ; immunology ; Viral Vaccines ; administration & dosage ; genetics ; immunology

OBJECTIVE: To determine the immune-protective effect of Japan Schistosoma (Chinese mainland strain) 23 kD membrane protein-heat shock protein (SjC23-Hsp70) DNA vaccine plus adjuvantinduced interleukin-12 (IL-12) plasmid DNA on Schistosoma japonicum infection in water buffalos. METHODS: Forty-five health water buffalos (8-10 months old) in non-endemic area of schistosomiasis were randomly assigned into group A (SjC23-Hsp70+IL-12, 300 μg), group B (SjC23+IL-12, 300 μg) and group C (pVAX+IL-12, 300 μg), 15 in each group. Each buffalo was immuned by shoulder intramuscular injection for 3 times, at an interval of 28 days. Twenty-eight days after the last immunization, each buffalo was infected with 1000 Japan cercariae of Schistosoma. Fecal examinations were conducted 2 days and 1 day before the perfusion, and on the day of perfusion. The number of hatching miracidia and eggs per gram feces was recorded. Fifty-six days after the infection, the buffalos were sacrificed and perfused via the descending aorta. The recovered adult worms and eggs in the liver tissue were counted. RESULTS: We compared group A and B with group C: the estrogen reduction rate was 45.7% and 26.61%; bug reduction rate was 44.51% and 25.84%; the fecal egg reduction rate was 41.1% and 31.63%; the miracidium reduction rate was 48.11% and 38.07%; and the liver egg reduction rate was 43.39% and 31.95%. The above rates in group A were higher than those in group B (P<0.05). CONCLUSION SjC23-Hsp70 DNA vaccine combined with IL-12 may have a significant immunoprotective effect on buffalos.
Animals ; Antigens, Helminth ; immunology ; Buffaloes ; Cattle ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Helminth Proteins ; immunology ; Immunization ; methods ; Interleukin-12 ; genetics ; immunology ; Membrane Proteins ; immunology ; Schistosomiasis japonica ; immunology ; prevention & control ; veterinary ; Vaccines, DNA ; administration & dosage ; immunology ; Vaccines, Synthetic ; immunology

To develop a new Hepatitis C virus (HCV) DNA vaccine ,We explored strategies for optimizing the immunogenicity of HCV DNA vaccine in fusion with dendritic cell-targeting molecules (scDEC, a single-chain antibody against the murine DC cell surface molecule DEC205). We constructed the DNA vaccine plasmids expressing the HCV non-structural protein NS3 alone or in combination with DEC205 as a fusion protein and identified the expression of the molecules of interest by transient transfection of 293 cells with the resultant DNA vaccine plasmids. Then BALB/C mice were immunized with these plasmids by the injection in combination with electroporation. The NS3-specific IgG antibody(ELISA) and cellular immunity (IFN-gamma ELISPOT) were analyzed post twice immunization. Our results showed that: the single-chain antibody against DEC205 fused with vaccine antigen NS3 significantly enhanced the immunogenicity of new HCV DNA vaccine, the intradermal injection in combination with electroporation using caliper electrodes resulted in most robust NS3-specific antibody and T cell immune response. In conclusion,immune response for the HCV NS3 protein-encoding DNA vaccine was enhanced significantly when targeting antigen NS3 to DCs by scDEC. The present strategy could merit further study in the context of other prophylactic and therapeutic DNA based vaccines.
Animals ; Cell Line ; Dendritic Cells ; immunology ; virology ; Enzyme-Linked Immunospot Assay ; Female ; HIV Antibodies ; immunology ; Hepacivirus ; genetics ; immunology ; Hepatitis C ; immunology ; prevention & control ; virology ; Humans ; Mice ; Mice, Inbred BALB C ; Vaccines, DNA ; administration & dosage ; genetics ; immunology ; Viral Nonstructural Proteins ; administration & dosage ; genetics ; immunology

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.
Animals ; Antigens, Protozoan/administration & dosage/genetics/*immunology ; CD8-Positive T-Lymphocytes/*immunology ; COS Cells ; Cercopithecus aethiops ; Humans ; Lymphocyte Activation ; Malaria, Vivax/*immunology/parasitology ; Membrane Proteins/administration & dosage/genetics/*immunology ; Mice ; Mice, Inbred BALB C ; Plasmodium vivax/genetics/*immunology ; Protozoan Proteins/administration & dosage/genetics/*immunology ; Protozoan Vaccines/administration & dosage/genetics/*immunology ; Vaccines, DNA/administration & dosage/genetics/*immunology