¹Institute of Health Sciences, Marmara University, Istanbul, Türkiye
²Department of Basic Pharmaceutical Sciences, Faculty of Pharmacy, Marmara University, Istanbul, Türkiye
³University of Health Sciences, Kartal Koşuyolu High Speciality Educational and Research Hospital, Istanbul, Türkiye DOI : 10.29228/jrp.2022.00 SARS CoV-2 belongs to the Coronaviridae family and is an enveloped virus with a positive polarity singlestranded RNA genome. The virus's spike protein, embedded in the viral membrane, is the most important antigenic protein involved in binding the virus to the host cell receptor. This protein is the basic component of vaccines developed against the virus due to its antigenic character. Therefore, it is crucial to produce this protein heterologously. This study evaluated the potential of ExpiSf9 and Hi5 insect cells infected with recombinant baculoviruses carrying the spike gene to synthesize the spike protein. The synthesis of the spike protein in infected cells was analyzed using SDS-PAGE/silver staining, Western blotting, and immunofluorescence techniques. High levels of spike expression were detected in virusinfected cultures at 72 hours post-infection compared to cellular proteins. The immunostaining results showed that spike proteins were present in the cell cytosol as aggregates, indicating that the proteins were transported via the endoplasmic reticulum-Golgi transport pathway. The Western blot analysis revealed that the spike proteins undergo posttranslational modifications, such as glycosylation and proteolytic cleavage, in both insect and mammalian cells. Based on this data, it has been concluded that the baculovirus expression system is a suitable and cost-effective method for producing the spike protein. This protein can be used as an antigenic component in the subunit vaccine against Covid- 19. Keywords : Coronaviruses; SARS CoV-2; recombinant spike protein; Covid-19; baculovirus; insect cells