Fig. 4

Cyclophilin B interacts with Basigin (CD147/BSG), a critical merozoite invasion receptor on RBCs. a Co-localization of CypB and BSG on the surface of the RBC. RBCs were fixed and incubated with anti-CypB (mouse monoclonal) and anti-BSG (rabbit polyclonal) antibodies. The cells were stained with fluorochrome-conjugated secondary antibodies against CypB (green) and BSG (red) followed by confocal microscopy. CypB and BSG co-localized on the RBC surface with a Pearson’s coefficient of 0.53. b Merozoites were incubated with 25 µM of BSG protein for 2 h and detection was carried out using anti-CD147 antibody (rabbit polyclonal) and secondary fluorochrome-conjugated (red), followed by confocal microscopy. c CypB and BSG bind together on the merozoite surface. Merozoites were incubated with CypB and BSG proteins (25 µM each) for 2 h and binding was detected using anti-CypB (mouse monoclonal) and anti-BSG (rabbit polyclonal) antibodies followed by secondary antibodies and confocal microscopy. Supplementary Fig. 5 illustrates in vitro interaction assays between CypB and BSG. Scale bar = 5 µm