Design, Synthesis and In Vivo Evaluation of a Candidate Fusion Epitopic Construct Vaccine Based on M۲e, HA۱, HA۲, NA and NP Fragments of the Highly Pathogenic Avian H۵N۱ Influenza Virus

The H۵N۱ subtype of Influenza virus, have a very high pathogenicity and lethality in humans and animals, and the need to develop new vaccines with a wide range of effects against this pathogen seems to be very crucial. Today, a highly regarded solution to this problem is to design and produce recombinant vaccines using the conserved peptide of influenza viruses. By searching in international databases, the peptide sequence of M۲e fragment of H۵N۱ viruses isolated from Iran and a variety of conserved peptide sequences of fragments of HA۱, HA۲, NA and NP of other H۵N۱ virus was obtained for both MHC receptors in mice. Then these fragments along with a PADRE sequence were connected by bioinformatics programs to design a fusion epitopic construct construct. Afterwards the designed construct was optimized for expression in E.coli BL۲۱. After expression, and purifications of fusion epitopic construct, it was injected subcutaneously (SC) into the hindlimb muscles of ۶ – ۸ old week female BALB/c mice. Three weeks after the end of the second immunization, both groups of immunized and control mice were weighed and checked for any side effects at the injection sites. Eventually the mice were euthanized and blood was collected from their heart to determine the total IgG antibody before and after immunization by ELISA. No local inflammation or complications were observed at the SC injection sites until the end of the experiment and autopsy of mice showed no bleeding or lesions in organs especially liver and spleen. The weight of the mice did not change significantly during the immunization period. The total IgG level measured by average OD value in the serum of immunized mice showed five times more (۵.۸۸۱ ng/ml) compared to the control group (۱.۱۴۳ ng/ml). Our results demonstrated a highly significant IgG antibody response following SC administration of immunogenic recombinant peptide in mice.

کلیدواژه ها:

influenza virus ، H۵N۱ ، fusion epitopic construct ، vaccine ، IgG