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Newcastle disease is a fatal viral disease which is highly contagious that affects most species of birds and is a major economic threat in the poultry industry. Both the HN and F glycoproteins of Newcastle disease virus (NDV) are essential for pathogenicity and virus infectivity. This study describes immunization of DNA vaccines encoding the HN, F or both the genes of New castle disease virus. In our previous study, the antigen expression of the insert genes has been validated in vitro by Western Blotting and Indirect Immunosenest. In this study, ELISA and HI analysis of the in vivo experiment on SPF (specific Pathogen Free) chickens showed the induction of humoral responses by the DNA vaccines. Our finding indicated that twice vaccination with pDNA was able to elicit significant antibody titers (P< 0.05) by either monocistronic (pIRES/HN and pIRES/F) or bicistronic (pIRES/F/HN) plasmid, after one week of second pDNA vaccination (booster). The results proposed that DNA immunization of chickens at second vaccination had enhanced the antibody response successfully. Also, it revealed that vaccination with the co-expression plasmid pIRES/HN/F can induce a stronger antibody response than vaccination with pIRES/HN or pIRES/F alone.

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Objective: The global HIV epidemic continues to expand and exceeding previous predictions. An effective vaccine represents the best hope to curtail the HIV epidemic. DNA vaccines induce humoral and cellular responses and mimic live vaccines without their pathogenic potential. The importance of CD8+ CTL responses in controlling HIV and SIV viremia has led to production of a series of vaccine candidates that effectively induce these responses. It is now widely believed that an HIV vaccine strategy must stimulate both a strong humoral (antibody) as well as cell-mediated (CTL) immune response.The p24 and gp41 play many important roles in host-virus interaction and pathogenesis. These proteins are considered as attractive vaccine candidate in which their immunogenecity and immunomodulatory effects have been confirmed. Materials and Methods: In this study, a construct, pcDNA3.1Hygro- (p24-gp41), was evaluated as a DNA vaccine candidate in Balb/C mice for generation of effective cellular immune responses. For immunizing, we used dendrosome, a novel family of vehicles for transfection and therapy. IFN-γ cytokine production and total antibody were detected by ELISA. Lymphoprolifration assay was performed by MTT test. Results: ELISA and MTT assays confirmed that the cited p24-gp41 fusion gene is able to enhance immune responses in mice. Conclusion: The construct that was used in this research can be a good candidate for DNA vaccine against HIV-1, if the future complementary tests demonstrate the same trends of immunogenic responses shown in this study.

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Aims: One of the challenges of today's world and also global health priorities is pandemicity of AIDS. Studies have shown that the scope and breadth of the immune responses induction are very effective to protect against HIV. Moreover, simultaneous induction of humoral and cellular immunity responses increases the effectiveness of candidate HIV vaccines. Hence, new approaches such as polyepitopic vaccine strategy and addition of different adjuvants in HIV vaccines’ formulations have been recently considered.
Materials and Methods: In the present study, eukaryotic expression vector (pcDNA3.1-tat/pol/gag/env) was transformed and amplified in the prokaryotic host cells E. coli (DH5α). After vector extraction, it was concentrated and formulated alone and in combination with Alum adjuvant and used as DNA candidate vaccines. DNA candidate vaccines were, then, subcutaneously injected to the BALB/c mice on 0, 14, and 28 days and elicited humoral and cellular immunity responses were finally evaluated.
Findings: The results showed that the candidate DNA vaccine could not efficiently induce immunity responses (both humoral and cellular responses) by subcutaneous route injection.
Conclusion: This observation can be due to a defect in each of the steps of vector harvesting by the target cell to express the surface presentation of the epitopes on the one hand, or the inefficiency of the subcutaneous injection method on the other. Therefore, other vaccines’ injection and deliveries routes along with addition of other adjuvants in vaccine’s formulations could induce immunity responses efficiently and increase vaccine efficacy.

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Objective: Toxoplasmosis can lead to severe pathological effects in both infected humans and animals. The various DNA vaccines against Toxoplasma compose of single or cocktail antigens have been investigated but they have partial protective against disease. In this study, we used pcROP1 as a DNA vaccine and aluminium phosphate and aluminium hydroxide to compare their efficacy as mineral adjuvants. Materials and Methods: BALB/c mice immunized with pcROP1 alone or with co-administration of Alpo4 or Alum and the effectiveness of these two adjuvants were compared using lymphocyte proliferation assay, cytokine and antibody assay and survival time. Results: The group co-administered alum elicited stronger humoral and Th1-type cellular immune responses than the group co-administered Alpo4, while immune response in group administered with pcROP1 alone is higher than them. When challenged with Toxoplasma gondii RH strain, mice immunized with or without alum had significantly higher survival rates, whereas there was no notable enhancement of survival rate in Alpo4 group (P≤0.05). Conclusions: Our result suggest that pcROP1 plus alum and aluminium phosphate not strongly potentiate the efficacy of this DNA.

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Objective: More than 99% of cervical cancers contain human papillomavirus (HPV), particularly the high-risk HPV type 16 (HPV-16). Among therapeutic HPV vaccines, DNA vaccines have emerged as a potentially promising approach. The main problem with DNA vaccination is the efficient delivery of the genes. A different delivery system has been used to bypass this problem. Archaeosomes have shown high stability during oxidative stress. In this study, we prepared the archaeosome Halobacterium salinarum polar lipid and used it as a delivery system and adjuvants for formulation with the E6/E7/L1 chimeric plasmid as an HPV vaccine candidate. Methods: The recombinant pIRES2-plasmid that contained an E6/E7/L1 chimeric gene of HPV were purified after extraction. Halobacterium salinarum total polar lipids were prepared according to a method by Bligh and Dyer. The archaeosome-pDNA complex was prepared by the addition of plasmid DNA to an archaeal lipid solution and the mixture kept at room temperature to allow for complex formation. Particle sizes and zeta potential of the samples were measured using dynamic light scattering. We measured the relative tumor volume after administration of TC-1 cells to C57BL/6 mice. Results: Zeta potential of the anionic archaeosomes was -6.84mV while archaeosome-pDNA complexes were -29 mV. The highly negative zeta potential of archaeosome-pDNA complexes demonstrated excellent loading of the plasmid on the nanoparticle surface and electrostatic stability. The results showed that the archaeosome-containing E6/E7/L1 chimeric gene significantly inhibited the rate of tumor growth in comparison with the control groups. Conclusion: Archaeosomes are easy and cost-economic to prepare and highly stable. They may hold tremendous promise as vaccine delivery vehicles