Background & Objectives: Lipopolysaccharide (LPS) is the main antigenic structure expressed on the surface of smooth strains of Brucella. It has been shown that Outer membrane vesicle (OMV) of Neisseria meningitidis efficiently promote IgG and IgM response against the administrated antigen as an adjuvant. The aim of this study is to evaluate the effect of LPS-OMV noncovalent complex in producing of T helper 1 cytokine (IFN-γ) and T helper 2 cytokines (IL-4 and IL-10) in mice.

  Methods: LPS extracted by an optimized method based on hot phenol-water extraction. Groups of six BALB/c mice were injected subcutaneously with LPS alone, LPS with Freund adjuvant and LPS-OMV complex on 0, 14 and 28 days. Levels of IFN-γ, IL-4 and IL-10 were evaluated in spleen cell suspension supernatant by ELISA.

  Result: Immunization with B. abortus LPS significantly induced high level of IFN-γ in comparison to the other groups immunized with LPS-OMV and LPS+ adjuvant (p<0.05). In contrast, lower levels of IL-4 and IL-10 were elicited by LPS in the rest groups. Immunization with the non-covalent complex of B. abortus LPS-N. meningitidis serogroup B OMV caused a significant increase of IL-4 and IL-10 compared with the mice immunized with B. abortus LPS (p<0.05), while the titer of IFN-γ is still significantly higher than IL-4 and IL-10 (p<0.05).

  Conclusion: The raise of IFN-γ following the immunization with all of the compounds (LPS, LPS-OMV non-covalent complex and LPS+adjuvant) indicates the activation of Th₁ population that would be correlated to the clearance of the organism due to the amplification of anti-microbial activity of Polymorphonuclear cells. Low levels of IL-4 and IL-10 following the immunization with all compounds would be a sign of Th₁ responses dominancy or inhibition of Th₂ population proliferation and activity. Such a cytokine pattern would be a sign of the efficiency of brucellosis subunit vaccine because Th₂ responses basically have no role in the immune responses against Brucella and may lead to the persistence of intracellular infection.

  Background & Objective: Gene therapy and administration of recombinant protein are common approach in treatment of genetic disorders. But many obstacles including frequent administration of desired gene, random integration into the host genome and low expression of protein encourage scientists to design an episome which remains in high copy number in eukaryotic cells and produces desired protein in suitable manner by viral proteins. The aim of this study is designing and construction of a plasmid containing mutated large T antigen of SV40 to develop a safe vector with high replication.

  Methods: Suitable mutant for creating large T antigen was analyzed by MODELLER software and finally appropriate structures were selected. Target mutation was created in the nucleotide sequence of large T antigen by PCR method. Mutated large T antigen gene was cloned in to the IRES2-EGFP. All clones were analyzed by PCR, restriction analysis and sequencing. HEK293 and CHO cell lines were transfected by final construct and transfected cells were observed by fluorescent microscope for 40 days. Plasmid and genomic DNA were extracted from remained cells and overlap PCRs performed on them to confirm their circularity.

  Result: This plasmid, containing a mutated large T antigen of SV40, can be replicated in eukaryotic cells and then can be used in gene therapy and recombinant protein production with high safety.�

  Conclusion: The results of PCR, restriction analysis and sequencing confirm the authenticity of construct. The transfection of HEK293 and CHO cell lines showed replication of constructed plasmid in them.