Designing of A Multi-epitope Recombinant Protein, Consisting of Several Conserved Epitopes from Hemagglutinin Protein of the H1N1 and H5N1 Strains of Influenza Virus by Immunoinformatics Approaches

Introduction: According to marked advances in bioinformatics studies, development of influenza vaccines has been greatly modified in many studies. In this study, we have designed a multi-epitope recombinant protein, consisting of several conserved epitopes from Hemagglutinin protein of the H1N1 and H5N1 strains of Influenza virus by immunoinformatics approaches. Materials and Methods: The registered sequences of hemagglutinin proteins from H1N1 and H5N1 strains have been analyzed and selected epitopes have been chosen and directed for further analysis. After investigation of immunological and physicochemical parameters, the selected regions were fused together by linkers and sequence of target constructs was determined following codon optimization. The target construct has been integrated into BamHI/XhoI cleavage sites of PET32a+ expression vector. Results: A physicochemical analysis revealed that the designed recombinant protein has 214 amino acid with molecular weight of 22.451 kDa. The isoelectric point was determined as 7.25 , solubility of 100% and  Extinction coefficient of 60170 M-1cm-1.finally, after codon optimization, the Codon Adaptation Index (CAI) was calculated as 0.95. Discussion: According to these results, it has been predicted that designed multiepitop recombinant protein has reasonable and unique immunological properties. The expressed protein could be used for future immunological studies against type A influenza virus