Expression of PfGARP on the surface of CHO-K1 cells. (A) Malaria proteins, PfGARP-M and EBA-175, were inserted into pRE4 vector, a chimeric construct of HSVgD1, and expressed on the surface of mammalian CHO-K1 cells. Location of epitopes for ID3 and DL6 are shown in the vector cartoon, which was adapted from Chitnis and Miller.²⁸  (B) IF analysis of CHO-K1 cells transfected with PGARP-M, EBA-175, and empty vector confirming the surface expression of the respective proteins using mouse anti-ID3 mAb and goat anti-mouse immunoglobulin G antibody with Alexa Fluor 633. (C) CHO-K1 RBC-binding assay. Rosette-like structures were observed in PfGARP-M–transfected CHO-K1 cells (left panel; original magnification ×40). As expected, robust rosettes-like structures were observed in the EBA175-transfected CHO-K1 cells (upper right top panel), whereas no such structures were seen in CHO-K1 cells transfected with empty pRE4 vector (right lower panel). (D) A representative estimate of the rosette-like structures is shown in the bar graph. Quantification of rosette-like structures shown in panel C.