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Background: The importance of VP2 protein of canine parvovirus to bind to human cancer cells and to detect the virus in veterinary detection kits has motivated a lot of research on the production of this protein. In this project, a surface gene of canine parvovirus (VP2) was cloned and expressed in a prokaryotic vector system and its expression was optimized in a specific cell-free prokaryotic expression system. Materials and Methods: In this experimental study, plasmid pET-21aVP2 was constructed by cloning the PCR product of VP2 gene of canine parvovirus into the plasmid expression pET-21a vector. The best sequence was analyzed through PCR and it was followed by confirmation with sequencing and restriction digestion. To produce VP2 protein, plasmid pET-21aVP2 was transferred into Escherichia coli, Rosetta (DE3) strain, and the expression of this protein was induced by IPTG. The production of VP2 protein in both systems was evaluated using SDS PAGE technique. The expressed protein was checked with monoclonal antibody against VP2 protein by Western blotting technique. Results: Successful cloning of VP2 protein was confirmed by enzymatic digestion and sequencing. The expression of VP2 protein in bacterial and cell-free prokaryotic systems was verified by SDS PAGE and the specific band in Western blotting also confirmed the VP2 protein. Conclusion: The results of this study showed that VP2 gene was amplified in the cloning phases and it was successfully cloned in the expression vector. Protein expression was confirmed in both bacterial and cell-free prokaryotic systems.

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Background: Parvovirus 4 (PARV4) was first discovered in 2005, in a hepatitis B virus–infected injecting drug user (IDU). To date, the best evidence about PARV4 transmission is parenteral roots and comes from IDU individuals. It seems that the prevalence of the virus in the normal population is very low. In this study, we investigated the prevalence of PARV4 virus among patients with chronic HCV infection compared with healthy controls and related risk factors among these groups.

Materials and Methods: A total of 206 patients, including 103 patients with chronic HCV infection and 103 healthy controls, were studied by use of nested-PCR and also real-time PCR techniques.

Results: AST enzyme levels with a mean of 40.45+34.84 and 18.58+5.9 in patients and healthy group respectively and the amount of enzyme ALT among patients with a mean of 40.45+35.75 and 21.50+11.35 in patients and healthy group respectively, were reported. Finally, after screening all DNA samples from patients and controls, we discovered that none of these people are infected with the PARV4 virus.

Conclusion: This study is the first to investigate the occurrence of PARV4 among HCV patients in Iran. The results show that, the virus is not important in Iranian population, even in patients with blood born infections such as HCV and further studies in other areas and various groups are required.