Native PfRH5, PfRipr, and CyRPA interact to form a 200-kDa multiprotein complex in the parasite. (A) Schizont lysate analyzed by anion-exchange chromatography detected PfRH5, PfRipr, and CyRPA to coelute at 350 mM NaCl (peak 1). (B) SEC-200 analysis of peak 1 proteins detected PfRH5, PfRipr, and CyRPA in fractions (32–36) corresponding to 200 kDa. BN-PAGE of SEC fraction 34 (C) and culture supernatant (D) confirmed that PfRH5, PfRipr, and CyRPA coexisted as an intact 200-kDa native protein complex. *PI represents the corresponding preimmune sera. (E) SEC-200 analysis of culture supernatant also detected PfRH5, PfRipr, and CyRPA in fractions (35–38) corresponding to ∼200 kDa. β-Amylase and alcohol dehydrogenase (ADH) are SEC molecular weight standards.