Construction and immunogenicity analysis of a recombinant baculovirus targeting the N protein of SARS-CoV-2

Objectives: This study aimed to construct recombinant baculoviruses capable of expressing the nucleocapsid N protein of SARS-CoV-2 and to assess the effects of co-administration with sodium butyrate on its expression and immunogenicity.

Results: The recombinant BmNPV expressed green fluorescent protein in BmN cells and N protein in mammalian cells. The addition of sodium butyrate significantly enhanced the expression of N protein in HEK293T cells. Following intramuscular injection of recombinant BmNPV into mice, specific antibodies against the N protein were detectedon day 7, 21, and 35. Co-administration with sodium butyrate (1000 mg/kg body weight) significantly enhanced the immunogenicity of the recombinant virus.

Conclusions: Recombinant BmNPV expressing the SARS-CoV2 N protein successfully inducedthe anti-N immunogenicity in mice, providing a solid foundationfor the development of novel subunit vaccines against SARS-CoV-2.