Isfahan University of Medical Sciences Journal of Isfahan Medical School 1027-7595 39 617 2021 05 22 Recombinant Expression of Hemagglutinin Protein of Iranian Swine influenza A (H1N1) in the Insect Cells Using Baculovirus System Recombinant Expression of Hemagglutinin Protein of Iranian Swine influenza A (H1N1) in the Insect Cells Using Baculovirus System 181 188 12281 10.22122/jims.v39i617.13912 FA Journal Article 2022 04 01 <strong>Background:</strong> Influenza virus, which is a decisive agent of influenza, attracted interest because of the event of the annual epidemic among a wide range of animal and human hosts. This study aimed to express the hemagglutinin protein of Iranian swine Influenza A (H1N1) through a baculovirus system in SF9 cells to produce a new recombinant vaccine. <strong>Methods:</strong> Hemagglutinin gene of Swine H1N1 virus was amplified with specific primers containing restriction enzymes site, and then cloned. Afterward, the vector was transformed to DH10Bac using Bac-to-Bac system in order to produce a recombinant bacmid. Hemagglutinin expression and its biological activity were assessed using molecular and immunization tests. <strong>Findings:</strong> The target rHA in length, 1710 bp, was produced and expressed in transfected SF9 cells with a size of ~66 kDa. The infected cells expanded in size and their nucleus, and desiccated from the surface of the cell culture as a granular. They could absorb chick red blood cells (RBCs), and appear as cell aggregates forty-eight post-infection. The fact that infected cells were unable to form cell clamp showed the test's accuracy and inhibition of hemodesorption activity. The amount of protein obtained was 10.76 µg/100 µl, equal to 0.1 mg/ml. <strong>Conclusion:</strong> The baculovirus expression system could express the recombinant protein in the insect cell. Therefore, it may be a well-suited alternative to produce a new generation of the vaccine instead of egg-based and cell-culture-based generation vaccines. <strong>Background:</strong> Influenza virus, which is a decisive agent of influenza, attracted interest because of the event of the annual epidemic among a wide range of animal and human hosts. This study aimed to express the hemagglutinin protein of Iranian swine Influenza A (H1N1) through a baculovirus system in SF9 cells to produce a new recombinant vaccine. <strong>Methods:</strong> Hemagglutinin gene of Swine H1N1 virus was amplified with specific primers containing restriction enzymes site, and then cloned. Afterward, the vector was transformed to DH10Bac using Bac-to-Bac system in order to produce a recombinant bacmid. Hemagglutinin expression and its biological activity were assessed using molecular and immunization tests. <strong>Findings:</strong> The target rHA in length, 1710 bp, was produced and expressed in transfected SF9 cells with a size of ~66 kDa. The infected cells expanded in size and their nucleus, and desiccated from the surface of the cell culture as a granular. They could absorb chick red blood cells (RBCs), and appear as cell aggregates forty-eight post-infection. The fact that infected cells were unable to form cell clamp showed the test's accuracy and inhibition of hemodesorption activity. The amount of protein obtained was 10.76 µg/100 µl, equal to 0.1 mg/ml. <strong>Conclusion:</strong> The baculovirus expression system could express the recombinant protein in the insect cell. Therefore, it may be a well-suited alternative to produce a new generation of the vaccine instead of egg-based and cell-culture-based generation vaccines. https://jims.mui.ac.ir/article_12281_fb51aea2099d8fbdfe50a5cd69ff8e50.pdf