[Prokaryotic expression of chimeric trimer protein [3M[2]e-HA2-NP] derived from conserved domains of influenza virus A/H1N1 as a promising universal subunit vaccine]

Background and Aim: Influenza A virus is an important respiratory pathogen which can cause high rates of morbidity and mortality during seasonal epidemics and pandemics. Current vaccines are not capable of producing effective immunity against different influenza virus subtypes. Designing universal vaccines using conversed domains of influenza virus antigens can overcome this limitation. The ectodomain of influenza M[2] protein [M[2]e], the hemagglutinin stalk domain [HA2], and nucleoprotein [NP] are the most conserved sequences among subtypes of influenza A viruses. The aim of this study was to attach part of the NP gene into the binary structure of 3M[2]e-HA2 and assessment of expression of a chimer trimer protein in prokaryotic system. This recombinant protein is considered as a promising antigenic candidate for a universal vaccine production

Materials and Methods: First, part of the NP gene segment of human influenza A/H1N1[PR/8/34]was amplified by PCR using designed specific primers. This amplified gene was cloned into pGEM-TEasy cloning vector. Then, the confirmed segment of NP gene was subcloned into PET28a/3M[2]e-HA2 recombinant expression vector, downstream of the HA2 segment. After confirmation of cloning, the chimer protein was expressed in E.coli BL21[DE3]

Results: The results of colony PCR, restriction enzyme digestion and sequencing indicated that the NP gene segment was correctly cloned into PET28a/3M[2]e-HA2. Chimer protein expression was analyzed by SDS-PAGE and confirmed by Western blotting

Conclusion: Design and production of recombinant protein [3M[2]e-HA2-NP] could be an important step towards the development of a universal influenza vaccine

Phylogenetic comparison of influenza virus isolates from three medical centers in Tehran with the vaccine strains during 2008-2009

Influenza virus is a major infectious pathogen of the respiratory system causing a high degree of morbidity and mortality annually. The worldwide vaccines are decided and produced annually by The Worldwide vaccines are decided and produced annually by World Health Organization and licensed companies based on the samples collected from all over the world. The aim of this study was to determine phylogenecity and heterogenecity of the circulating influenza isolates during 2008-2009 outbreaks in Tehran, compare them with the vaccine strains that were recommended by WHO for the same period. Nasopharyngeal swabs [n=142] were collected from patients with influenza and influenza-like illness. Typing and subtyping of the isolates were performed using multiplex RT-PCR and phylogenetic analysis was carried out for hemagglutinin genes of the isolates. Fifty out of 142 samples were positive for influenza A virus, and no influenza B virus was detected. Phylogenetic analyses revealed that the A/H1N1 isolates were related closely to A/Brisbane/59/2007, and the A/H3N2 isolates were close to A/Brisbane/10/2007 vaccine strains. The findings of the present study demonstrate that the A/H1N1 was the predominant subtype of human influenza virus among the patients studied in Tehran during 2008-2009 winter seasons. In addition, some amino acid variation was found in Tehran/2008/H1N1 isolates from the 2008-2009 vaccine strain, but the H3N2 isolates showed higher genetic resemblance to the vaccine strain

Isolation and cloning of human papillomavirus 16 L1 gene from Iranian isolate

To isolate and construct cloning and expression vectors containing human papillomavirus [HPV16-L1] gene as target for application as recombinant vaccine. The study was performed in 2007 in Tarbiat Modares University, Tehran, Iran. Four genital specimens DNAs were amplified with the use of HPV type-specific primers based on HPV-16 L1, E6, and E7 genes. The polymerase chain reaction products were cloned into suitable cloning and expression vectors and were confirmed by restriction enzyme analysis and sequencing. The desired plasmids were sequenced and indicated 99% homology with those submitted full length L1 sequences in the GenBank. The results showed that there was 99% homology between our product and those mentioned in the GenBank. Nowadays empty viral capsids, termed virus-like particles, are synthesized with the use of microbial or cellular expression systems. Therefore, it can be concluded that the Iranian HPV16 full length L1 sequence is very similar to the other sequences in the GenBank and it can be used as a candidate gene in prophylactic vaccine for cervical cancer