Recombinant Expression of Hemagglutinin Protein of Iranian Swine influenza A (H1N1) in the Insect Cells Using Baculovirus System

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.

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.

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 postinfection. 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.

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-culturebased generation vaccines.