Extended Data Fig. 10: Scheme of receptor-based antibodies hijacking binding of RIFIN to host inhibitory receptors.
From: Structural basis of malaria RIFIN binding by LILRB1-containing antibodies
a, Immune cells such as B cells, T cells and natural killer (NK) cells express the inhibitory receptors LILRB1 or LAIR1 on the cell surface. Infected erythrocytes express surface variant antigen RIFINs that can target host inhibitory receptors such as LILRB1 or LAIR1 for immune invasion. Cross-linking of HLA-I on cells with the LILRB1 D1D2 domain can deliver a negative regulatory signal to the LILRB1-expressing cells. LAIR1 binds to C1q or collagen-like domains. LAIR1, blue; C1q, yellow; LILRB1, red; HLA-I, grey; LILRB1-specific RIFIN, light pink; LAIR1-specific RIFIN, light blue. b, The host immune system developed natural receptor-based antibodies to combat the evasion mechanism used by infected erythrocytes. The LILRB1-containing antibody does not cross-react with RIFINs that are specific for LAIR1. Antibody heavy chain VH, dark green; constant region CH, grey; light chain VL, light green; light chain constant CL, light grey.
