Résumé
The impending influenza virus pandemic requires global vaccination to prevent large-scale mortality and morbidity, but traditional influenza virus vaccine production is too slow for rapid responses. In this study, bacterial system has been developed for expression and purification of properly folded HA1 antigen as a rapid response to emerging pandemic strains. Here, a recombinant H5N1 [A/Indonesia/05/05] hemagglutinin globular domain, the synthesized HA1 [1-320 amino acids], was amplified and cloned into pET-28a bacterial expression vector. Then, his-tagged HA1 protein was expressed in Escherichia coli BL21 under 1 mM IPTG induction. The protein expression was optimized under a time-course induction study and further purified using Ni-NTA chromatography. Migration size of protein was detected at 40 KDa by Western blot using anti-His tag monoclonal antibody and demonstrated no discrepancy compared to its calculated molecular weight. Since most antigenic sites are in the HA1 domain of HA, using this domain of influenza virus as antigen is of great importance in vaccine development. The ability of the antibody stimulation against HA1 expressed in bacterial cells is also examined using enzyme-linked immunosorbent assay [ELISA] analysis. Upon immunization of rabbits, oligomeric HA1 elicited potent neutralizing antibodies and high levels of serum antibody binding to HA1. Our findings suggest that HA1-based vaccines can be produced efficiently in bacterial systems and can be easily upscaled in response to a pandemic influenza virus threat
Résumé
Background: Foot -and- mouth disease [FMD] is endemic in Iran. Molecular techniques for diagnosis of persistent infection or carrier animals have shown a potential ability to improve the detection of a low genome copy number in samples
Objectives:The purpose of this study is to evaluate the frequency of foot and mouth disease viral carriers in slaughtered sheep in Mashhad industrial abattoir using RT-PCR
Methods: Samples were isolated from tonsil of 94 slaughtered sheep analyzed by RT-PCR experiment for the detection of FMD, identification of FMD virus serotypes and at the end nucleic acid sequencing were performed
Results: The results showed that the 23 samples [24/5 percent] were positive for the presence of FMD virus RNA, of which 89.9% of cases are type O and 3 cases of FMD samples did not respond. The results of the 1D genome sequencing of the nucleic acid virus showed that FMD virus of sheep [O/IRN/100/2010Sheep], has 92/02% similarity with the virus [O/IRN/67/2001-2005] and 88/42% similarity with the virus [O/IRN/15/2004-2008]
Conclusions: This study showed that the percentage of FMDV sheep carriers in Mashhad slaughterhouse was remarkable. Estimation of the frequency of carrier state in cattle and small ruminants is recommended as a monitor of control plan in the region