Fig. 1
Schematic representation of BDES constructs and the expression of functional proteins. a The pfcsp genes were cloned from P. falciparum (PfCSP19–373; PfCSP1) or synthesized with codon-optimization (synthesized PfCSP19–377; sPfCSP2). Both pfcsp genes were fused to the N-terminus of the gp64 gene (gp6421–512) and the transmembrane region of the vsv-g gene (VSV-G421–511; G). Expression of the PfCSP gene cassette was driven by a dual promoter (pCMV and pPolh). In the “Spider” type of BDES construct, but not in the “Spier” type construct, the human daf gene (hDAF) was displayed on virions under the control of the p10 promoter. b AcNPV-WT (non-recombinant control), BES-GL3-Spider (hDAF-displayed control), BDES-PfCSP1-gp64, BDES-sPfCSP2-Spier, and BDES-sPfCSP2-Spider (lanes 1–5, respectively) were lysed and subjected to the immunoblots with anti-PfCSP, anti-hDAF, or anti-VP39 Abs. (c–j) The morphologies of BDES-sPfCSP2-Spider (c–f) and BDES-sPfCSP2-Spier (g–j) are shown by transmission electron microscopy. The viral particles were reacted with a nonspecific mouse IgG (c, g), anti-FLAG mAb (d, h), anti-PfCSP mAb (e, i), or anti-DAF mouse mAb (f, j), and then incubated with a 5 nm colloidal gold-conjugated secondary Ab. Bars, 100 nm; Arrows, colloidal gold signals