FIG. 2.

Codon usage is critical for B19V capsid protein production. (A) Schematic diagram of plasmid construction. (B) Immunoblotting of VP2 production in CD36⁺ EPCs, CD34⁺ HSCs, and three different cell lines. Following transfection with individual plasmids, whole-cell lysates were prepared at 48 hpt and subjected to 4 to 20% SDS-PAGE, followed by immunoblotting with anti-VP2 antibody (MAb 8293). (C) IF assay. Cells transfected with pcDNA(p6)-optVP2 were immunostained with anti-VP2 antibody (MAb 8292) specific for a conformational epitope and then fluorescein isothiocyanate (FITC)-conjugated secondary antibody (green), followed by 4′,6-diamidino-2-phenylindole (DAPI) nuclear counterstaining. (D) Immunoblotting. 293T cells and CD36⁺ EPCs were transfected with pcDNA(p6)-optVP2 and subjected to immunoblotting with the anti-VP2 antibody (MAb 8293).