High morbidity and mortality of influenza virus infection makes it an important disease world-wide. Mouse is a very well-studied animal model for this disease with similar manifestation to human disease. It would be desirable to induce mucosal as well as circulating immune responses to obtain protection from infection and to decrease the spread of the virus. Cell mediated immunity (proliferative and cytolytic responses) is needed for long-term immunity. A new type of influenza subunit vaccine which can be given orally or parenterally has been developed to induce mucosal and circulating immune responses. This vaccine consists of membrane proteins rolled up in a unique phospholipid structures called protein cochleates. BALB/c mice were immunized three times with influenza glycoprotein-containing cochleates orally or intramuscularly, or they were primed orally or intramuscularly followed by two boosts with the alternate routes. Proliferation assays of spleen cells, and ELISA for IgA, IgG, and IgM of the sera and saliva from these mice shown some differences in the immune responses induced by different immunization regimens. Mucosal administration of the formulation led to secretory IgA in saliva while parenteral immunization resulted in circulating IgG. Increased proliferative responses as well as IgG following 2nd and 3rd administration, indicated the effect of boosting in all immunization regimens. Oral immunization with influenza virus envelope glycoprotein-containing cochleates led to protection from infection in the lungs and trachea following intranasal challenge with the live virus.

Background: Brucella is a type of bacteria that causes a disease known as brucellosis in both humans and animals. Many different vaccine formulations are available for this disease; however, vaccines based on epitopes have shown to be effective, especially in combating this pathogen. In the present study, we designed a multi-epitope vaccine against brucellosis using a chimeric protein that combines segments from various Brucella proteins known to contain both B- and T-cell epitopes. Methods: In this study, a vaccine candidate was developed using multiple epitopes derived from various proteins, including OMP31, TF, BLS, SOD, BP26, and L9. These epitopes were selected based on their high density of both B-cell and T-cell epitopes. The construct of the vaccine candidate was inserted into a pEGFP-N1 vector and introduced into HEK-293T cells. Subsequently, the vaccine was tested on different groups of mice; some received the expressed protein in E. coli, while others received the DNA vaccine candidate. An ELISA assay was employed to evaluate the humoral immune response. Results: Both the MEB protein (Pro/Pro) and pCI-MEB plasmid/MEB protein (DNA/Pro) groups showed a specific humoral response. The anti-DNA vaccine antibody titer did not rise as high as that of the protein groups; however, the observed protection indicated the efficiency of the DNA vaccine in activating the immune system.  Conclusion: While the chimeric DNA vaccine candidate induced a weaker humoral response, it remained effective in protecting against virulent strains of B. abortus and B. melitensis in the challenge route.

Current therapeutic approaches in allergic diseases especially asthma generally focus on using immunological strategies. According to the importance of Fc RI in controlling allergic response we used two extracellular regions of Fc epsilon receptor I (Fc RI) beta subunit peptides to design two peptide-based vaccines. Probably these peptides vaccines by triggering the immune response to Fc RI can reduce the allergic symptoms through blocking the IgE specific receptor. Two extracellular parts of Fc RI beta subunit were made by peptide synthesizer and conjugated with keyhole limpet Hemocyanin. These conjugated peptides were used and evaluated as therapeutic vaccines in allergic airway inflammation mouse model. Total IgE and anti ovalbumin specific IgE were measured in mice serum and compared in vaccinated and unvaccinated allergic mice. Histamine, prostaglandin D2 (PGD2), IL-4 and IL-13 were measured in bronchoalveolar lavage (BAL) fluid of vaccinated allergic mice versus unvaccinated and histopathologic examination were performed in studied groups. After vaccination of mice with each of the peptide vaccines the specific antibodies titer increased significantly in vaccinated groups versus unvaccinated. In histopathologic study, lavage eosinophil percentage and peribronchial inflammation in lung sections of vaccinated groups was decreased (p<0. 05). Also the allergic components including total IgE, anti ovalbumin specific IgE, histamine, PGD2, IL-4, and IL-13 showed substantial decline in vaccinated allergic mice. Thus targeting the extracellular regions of Fc RI beta subunit by peptide-based vaccines and induction of specific antibodies against them can reduce allergic responses in allergic mice model.