Expression of the GLFGAIAGF epitope of HA۲ protein of Influenza A virus in multiple display on filamentous M۱۳ phage

Background and Aim : Influenza A viruses (IAVs) are one of the primary cause of respiratory diseases. Influenza virus genome fragmentation, antigenic alteration partial and general due to point mutations and genetic rearrangement between the genomes of two influenza viruses that simultaneously infect one cell, modify the sequence of genes that encode HA and NA, creating new strains of the influenza virus. New strains of the virus have become a public health problem around the world by creating epidemics or pandemics. Studies have shown that the GLFGAIAGF epitope (residues ۱-۹) of HA۲ sequence is conserved in all strains of the influenza virus. Using this sequence, we can generate a new generation of vaccines containing protected peptides and eliminate the problem of drifting or shifting influenza A viruses. As this epitope has very low immunogenic potency, so it is not sufficient to protect against serious infections with new IAV strains. Filamentous phage M۱۳ can be used as display carriers and elevate the immunogenicity of foreign peptides. There are ۲۷۰۰ copies of pVIII per M۱۳ phage, so this system is capable of displaying a large number of foreign antigenic peptides to be inserted near the gpVIII N-terminus, followed by a hybrid phage in which the major pVIII protein exhibits the peptide epitope. Methods : In this study, a gene containing N-terminal epitope of HA۲ (۱-۹) which is conserved among all subtypes of IAVs, and gVIII gene of phages M۱۳ (from KM۱۳) was designed, synthesized and joined to each other by Assembly PCR technique. The HA۲ (۱-۹)-gVIII pIT۲ vector was transformed into competent E. coli TG۱ cells. The biological activities of hybrid phage were accessed after expression and purification. Results : The biological activities of hybrid phage were accessed after expression and purification. The sequencing result revealed that recombinant HA۲ (۱-۹)-gVIII genes have been cloned correctly in pIT۲ vector. The expression of GLFGAIAGF on the surface of phages M۱۳ was confirmed in Tricine-SDS-PAG, ELISA and Western blot using anti-HA۲ polyclonal antibody. Conclusion : This hybrid bacteriophage could be a good candidate for displaying HA۲ antigen and immunization.

کلیدواژه ها:

Phage display ، Influenza A virus ، HA۲ (۱-۹) ، M۱۳ phage ، gVIII.