Fig. 1.

Recombinant immunogens used in this study and reactivity with human antibodies. (A) Scheme of the engineered extracellular domains I to III of P. vivax AMA-1 as expressed by an adenovirus (AdPvAMA-1) or E. coli (PvAMA-1). SP, signal peptide; HASS, influenza virus hemagglutinin signal sequence. (B) AMA-1-containing bacterial lysates after IPTG (isopropyl-β-d-thiogalactopyranoside) induction (left panel), pure protein (middle panel), and specific reactivity with a P. vivax-positive human serum in an immunoblot assay (serum dilution, 1:2,000) (right panel). (C) Reactivity of the same serum (1:200 dilution) with HEK-293 cells infected with AdPvAMA-1 or a control adenoviral vector. Cells were visualized by fluorescence microscopy or phase-contrast light microscopy at a magnification of ×600.