Fig. 1

Construction of the HD-Ad_RBD vaccine. A HD-Ad_RBD vaccine schematic. ITR, adenovirus inverted terminal repeat; Pa, adenovirus packaging signal; CBA-P, chicken beta actin gene promoter with CVM enhancer; UbC-int, the first intron of the human ubiquitin C gene; SP, the human cystatin-S signal peptide; RBD, receptor binding domain of the SARS-CoV-2 spike protein; PolyA, transcription termination signal of the Bovine Growth Hormone gene; Stuffer DNA, noncoding human DNA used to make the vector genome large enough to be packaged. B Western blot analysis of RBD expression and secretion. Epithelial cells A549 and IB3 were transfected with HD-Ad_RBD at the indicated dosages and cell lysates and culture supernatants were prepared and subjected to Western blot analysis using anti-RBD antibodies