OBJECTIVETo study the expression of green fluorescent protein gene and immunogenicity of ES312 vaccine both mediated by Starburst polyamidoamine (PAMAM) dendrimers in vivo.

METHODSThe complex of green fluorescent protein or ES312 gene with Starburst PAMAM dendrimers were injected intramuscularly in Balb/c mice. The expression level and distribution of green fluorescent protein gene was detected by flow cytometer, Western blot and immunofluorescence assay. The immunogenicity of DNA vaccine was detected by enzyme-linked immunosorbent assay.

RESULTSThe expression of green fluorescent protein mediated by Starburst PAMAM dendrimers was found in heart, liver, spleen, lung, kidney, brain and injected muscle from 2 hours to 7 days after the vaccination. The highest expression level of the gene was detected in kidney, as well as in endothelial cells. The antibody response evoked by the DNA vaccine carried by the Starburst PAMAM dendrimers was significantly higher than that of the net DNA vaccination. Vaccination with Starburst PAMAM dendrimers elicited higher expression level of the gene in brain and kidney than with the net gene itself.

CONCLUSIONAs a novel non-viral DNA carrier with low self-antigenicity, Starburst PAMAM dendrimers have potential to mediate DNA transfer and expression in vivo.

Animals ; Biocompatible Materials ; pharmacology ; Dendrimers ; Drug Carriers ; pharmacology ; Female ; Green Fluorescent Proteins ; genetics ; pharmacokinetics ; Malaria Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Polyamines ; pharmacology ; Vaccination ; Vaccines, DNA ; immunology

In 1990, it was reported that the naked DNA encoding an antigen (so-called DNA vaccine) transduced directly into the muscle is able to induce immune responses just like antigen inoculation. Since then, a number of DNA vaccines against different diseases have been developed and shown to induce different levels of specific humoral and/or cell-mediated immunity. Efforts have been made to develop effective DNA vaccines against classical swine fever (CSF). This review covered the following aspects in the development and application of CSF DNA vaccines: construction and evaluation, application of adjuvants, combination with other vaccines and the existing problems and solutions.
Adjuvants, Immunologic ; pharmacology ; Animals ; Classical Swine Fever ; prevention & control ; Swine ; Vaccines, DNA ; biosynthesis ; immunology ; Viral Envelope Proteins ; genetics ; immunology ; Viral Vaccines ; biosynthesis ; immunology

Adjuvants, Immunologic ; pharmacology ; Animals ; Hepatitis B Surface Antigens ; immunology ; Hepatitis B Vaccines ; immunology ; Interleukin-15 ; pharmacology ; Killer Cells, Natural ; immunology ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; pharmacology ; Vaccines, DNA ; immunology

OBJECTIVETo investigate the adjuvant effect of co-stimulatory molecule CD137L on cellular responses to HBsAg DNA vaccination in mice.

METHODSEukaryotic expression vector containing the full length of mouse CD137L cDNA sequence (pcD137L) was transfected into NIH3T3 cells, and then the expression of CD137L mRNA and protein in the transfected cells were detected by RT-PCR, flow cytometry and immunofluorescence method, respectively. The BALB/c mice were co-immunized with pcD137L and HBsAg DNA vaccine (pcDS) by intramuscular injection. HBsAg-specific activity of splenic cytotoxic T lymphocyte (CTL) in the immunized mice was measured by LDH release assay. The splenic memory CD8+ T cells, and intracellular IFN-gamma and IL-4 of splenic lymphocytes and CD8+ T cells after immunization were detected by flow cytometry.

RESULTSThe NIH3T3 cells transfected with pcD137L efficiently expressed mouse CD137L mRNA and protein. HBsAg-specific CTL responses induced by the pcDS plus pcD137L group were much stronger than those induced by pcDS alone at a week after immunization (P<0.05). Compared to mice immunized with pcDS alone, CD44high and CD127(IL-7R) were all significantly up-regulated in memory CD8+ T cells from the mice immunized with pcDS combined CD137L both at a week and 12 weeks after immunization (P<0.05 and P<0.01). The pcDS plus CD137L group also elicited higher levels of IFN-gamma secreted by CD8+ T cells and splenic lymphocytes than pcDS alone at a week, 12 and 13 weeks after immunization, respectively (all P<0.01).

CONCLUSIONDNA, viral/immunol; Co-stimulatory molecule CD137L can enhance the Tc1 (type I) cell-mediated immunity, HBsAg-specific CTL and memory responses induced by HBsAg DNA vaccine, and may be an efficient adjuvant in priming HBV-specific T cell response.

4-1BB Ligand ; immunology ; pharmacology ; Adjuvants, Immunologic ; pharmacology ; Animals ; Female ; Hepatitis B Surface Antigens ; immunology ; Hepatitis B Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Vaccination ; methods ; Vaccines, DNA ; immunology

OBJECTIVETo study the effection of suppression murine melanoma growth by Intratumor injection of recombinant attenuated salmonella carrying heat shock protein 70 and herpes simplex virus thymidine kinase genes.

METHODSPlasmids PCMV-mtHSP70-IRES-TK were electro-transferred into salmonella typhimurium SL7207 to construct recombinant salmonella typhimurium. In vivo, Recombinant bacteria were injected into the mouse melanoma and the antitumor effection was observed. The survival period was recorded and safety analysis for this vaccine in each group.

RESULTSIn vivo, the mtHSP70/HSV-tk recombinant bacteria can suppress tumor growth significantly and extend survival. After recombinant Salmonella, 10(9) CFU/mL, was administered as an intratumoral injection, No diarrhea were observed. During therapy, body weight did not change markedly.

CONCLUSIONResults of the animal experiment suggests intratumor injection of recombinant attenuated salmonella typhimurium containing mtHSP70 and HSV-tk genes, has targeting ability against B16 tumor cell and could significantly inhibit tumor growth .

Animals ; Bacterial Proteins ; genetics ; immunology ; Cancer Vaccines ; genetics ; immunology ; pharmacology ; Genetic Therapy ; methods ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Melanoma, Experimental ; microbiology ; pathology ; therapy ; Mice ; Mice, Inbred C57BL ; Mycobacterium tuberculosis ; genetics ; Salmonella typhimurium ; genetics ; immunology ; Simplexvirus ; enzymology ; genetics ; Skin Neoplasms ; therapy ; Thymidine Kinase ; genetics ; immunology ; Vaccines, Attenuated ; genetics ; immunology ; pharmacology ; Vaccines, DNA ; genetics ; immunology ; pharmacology

Cholera toxin, which has been frequently used as mucosal adjuvant, leads to an irreversible activation of adenylyl cyclase, thereby accumulating cAMP in target cells. Here, it was assumed that beta2-adrenergic agonist salbutamol may have modulatory functions of immunity induced by DNA vaccine, since beta2-adrenergic agonists induce a temporary cAMP accumulation. To test this assumption, the present study evaluated the modulatory functions of salbutamol co-administered with DNA vaccine expressing gB of herpes simplex virus (HSV) via intranasal (i.n.) route. We found that the i.n. co-administration of salbutamol enhanced gB-specific IgG and IgA responses in both systemic and mucosal tissues, but optimal dosages of co-administered salbutamol were required to induce maximal immune responses. Moreover, the mucosal co-delivery of salbutamol with HSV DNA vaccine induced Th2-biased immunity against HSV antigen, as evidenced by IgG isotypes and Th1/Th2-type cytokine production. The enhanced immune responses caused by co-administration of salbutamol provided effective and rapid responses to HSV mucosal challenge, thereby conferring prolonged survival and reduced inflammation against viral infection. Therefore, these results suggest that salbutamol may be an attractive adjuvant for mucosal genetic transfer of DNA vaccine.
Adjuvants, Immunologic/*pharmacology ; Adrenergic beta-Agonists/immunology/*pharmacology ; Albuterol/immunology/*pharmacology ; Animals ; Antibodies, Viral/immunology ; Cercopithecus aethiops ; Cytokines/immunology ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Immunologic ; Herpes Simplex/immunology/*prevention & control ; Herpes Simplex Virus Vaccines ; Immunity, Mucosal/*drug effects/immunology ; Immunoglobulin A/immunology ; Immunoglobulin G/immunology ; Mice ; Simplexvirus/*immunology ; Th1 Cells/immunology ; Th2 Cells/immunology ; Vaccines, DNA/*immunology/pharmacology ; Vero Cells ; Viral Envelope Proteins/immunology

While currently therapeutic vaccines for chronic hepatitis B virus (HBV) infection are actively being developed to complement standard antiviral treatments, their immune activity, especially T cell activity, remains to be further improved. Here, we investigated the role of heat shock proteins HSP70 and gp96 on cellular and humoral immunity, using the main structure antigens of hepatitis core (HBcAg) and surface (HBsAg) as the DNA vaccine. By ELISPOT (enzyme linked immunospot assay), IFN-gamma intracellular staining, [3H]-thymidine incorporation and ELISA (enzyme linked immunosorbent assay) analyses, we showed that immunization with HBsAg/HBcAg DNA formulation along with HSP70 or gp96 induced significant increase of T-cell (about 1-6-fold) and antibody (about 20%-60%) immunity against HBsAg and HBcAg. These results may provide bases for designing HSP70- and gp96-based vaccines aimed at eliciting T-cell responses for therapeutic applications.
Adjuvants, Immunologic ; pharmacology ; Animals ; Female ; HSP70 Heat-Shock Proteins ; immunology ; Hepatitis B Core Antigens ; immunology ; Hepatitis B Surface Antigens ; immunology ; Hepatitis B Vaccines ; immunology ; Hepatitis B virus ; immunology ; Hepatitis B, Chronic ; immunology ; therapy ; Humans ; Immunoglobulin G ; immunology ; Membrane Glycoproteins ; immunology ; Mice ; Mice, Inbred BALB C ; T-Lymphocytes ; immunology ; Vaccines, DNA ; immunology

The aim of this study was to examine the efficacy of in ovo prime-boost vaccination against infectious bursal disease virus (IBDV) using a DNA vaccine to prime in ovo followed by a killed-vaccine boost post hatching. In addition, the adjuvant effects of plasmid-encoded chicken interleukin-2 and chicken interferon-gamma were tested in conjunction with the vaccine. A plasmid DNA vaccine (pcDNA-VP243) encoding the VP2, VP4, and VP3 proteins of the very virulent IBDV (vvIBDV) SH/92 strain was injected into the amniotic sac alone or in combination with a plasmid encoding chicken IL-2 (ChIL-2) or chicken IFN-gamma (ChIFN-gamma) at embryonation day 18, followed by an intramuscular injection of a commercial killed IBD vaccine at 1 week of age. The chickens were orally challenged with the vvIBDV SH/92 strain at 3 weeks of age and observed for 10 days. In ovo DNA immunization followed by a killed-vaccine boost provided significantly better immunity than the other options. No mortality was observed in this group after a challenge with the vvIBDV. The prime-boost strategy was moderately effective against bursal damage, which was measured by the bursa weight/body weight ratio, the presence of IBDV RNA, and the bursal lesion score. In ovo DNA vaccination with no boost did not provide sufficient immunity, and the addition of ChIL-2 or ChIFN-gamma did not enhance protective immunity. In the ConA-induced lymphocyte proliferation assay of peripheral blood lymphocyte collected 10 days post-challenge, there was greater proliferation responses in the DNA vaccine plus boost and DNA vaccine with ChIL-2 plus boost groups compared to the other groups. These findings suggest that priming with DNA vaccine and boosting with killed vaccine is an effective strategy for protecting chickens against vvIBDV.
Adjuvants, Immunologic/pharmacology ; Animals ; Antibodies, Viral/blood ; Birnaviridae Infections/immunology/prevention & control/*veterinary/virology ; Body Weight/immunology ; Bursa of Fabricius/immunology ; Chick Embryo ; *Chickens ; Histocytochemistry/veterinary ; Immunization/*veterinary ; Infectious bursal disease virus/genetics/*immunology ; Interferon-gamma/pharmacology ; Interleukin-2/pharmacology ; Organ Size/immunology ; Poultry Diseases/immunology/*prevention & control/virology ; RNA, Viral/chemistry/genetics ; Random Allocation ; Reverse Transcriptase Polymerase Chain Reaction/veterinary ; Specific Pathogen-Free Organisms ; Vaccines, DNA/*administration & dosage/immunology ; Vaccines, Inactivated/administration & dosage/immunology ; Viral Vaccines/*administration & dosage/immunology

We studied the immunogenicity of pseudorabies virus gC DNA vaccination by fusing the murine complement C3d receptor binding domain. First, pseudorabies virus gC gene was linked to four copies of C3d receptor binding domain (M284), and then cloned into the vector pcDNA3.1 to construct the recombinant plasmid sgC-M284. Through the experiment of immunized BALB/c mice, we found that the enzyme linked immunosorbent assay (ELISA) antibody titer for sgC-M284 was 17-fold higher than that for sgC alone, and protective rate of mice was augmented from 25% to 88% after lethal dose PrV (316 LD50) challenge. In addition, the IL-4 levels for sgC-M284 immunization approached that for the pseudorabies virus inactivated vaccine. In conclusion, we demonstrated murine C3d receptor binding domain fusion significantly increased Th2-biased immune response by inducing IL-4 production.
Adjuvants, Immunologic ; physiology ; Animals ; Antibody Formation ; immunology ; Binding Sites ; Cloning, Molecular ; Complement C3d ; genetics ; immunology ; Herpesvirus 1, Suid ; genetics ; immunology ; Interleukin-4 ; immunology ; Mice ; Mice, Inbred BALB C ; Pseudorabies Vaccines ; immunology ; Receptors, Complement 3d ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Swine ; Vaccines, DNA ; immunology ; Viral Envelope Proteins ; pharmacology ; Viral Fusion Proteins ; immunology

BACKGROUNDCholera toxin B subunit (CTB) was shown to be a potent adjuvant for protein immunogen, especially when inoculated through mucosal route. We aimed to optimize the expression approach for CTB and thereafter to determine the adjuvant effect on DNA vaccine.

METHODSWild type CTB coding gene was amplified and cloned into prokaryotic expression vector pET-30a, and the recombinant CTB was expressed in the presence of different concentration of chloramphenicol and isopropyl β-D-thiogalactoside. Purified recombinant CTB was mixed with HIV-1 AE2f tat-rev-integrase-vif-nef fusion gene DNA vaccine and female BALB/c mice were vaccinated with a DNA priming-recombinant vaccinia vectored vaccine boosting regimen through intramuscular injection. Interferon γ (IFN-γ) enzyme-linked immunospot (Elispot) assay was used to read out the specific T-cell immunity.

RESULTSChloramphenicol was essential for the efficient expression of recombinant CTB (rCTB) in pET-30a/BL21 (DE3) system and could be optimized at the concentration of 0.625 µg/ml in the presence of chloramphenicol. The purified rCTB could bind with GM1 efficiently. INF-γ Elispot data showed the T-cell response induced in CTB adjuvanted group ((734 ± 240) spot forming cells/10(6) splenocytes) was higher than that induced by non-adjuvanted ((520 ± 150) spot forming cells/10(6) splenocytes), all responses against different antigens were enhanced in parallel.

CONCLUSIONCTB could be efficiently expressed in the presence of chloramphenicol and purified CTB is functional and capable of enhancing the specific T cell responses elicited by DNA vaccine, the mechanism needs to be explored in the future.

Adjuvants, Immunologic ; pharmacology ; Animals ; Blotting, Western ; Chloramphenicol ; pharmacology ; Cholera Toxin ; metabolism ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; drug effects ; metabolism ; Female ; Mice ; Mice, Inbred BALB C ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Vaccines, DNA ; genetics ; immunology ; metabolism