Extended Data Fig. 4: Analysis of KIR2DL1-binding RIFIN diversity and KIR2DL1 allotypes.
From: RIFINs displayed on malaria-infected erythrocytes bind KIR2DL1 and KIR2DS1
a) Overlay of each copy of RBK21 in the unit cell of the crystal lattice, highlighting the loop which adopts different conformations (residues 244–256) and a change in angle of the helix from 166–176 of 11°. b) Electron density for representatives of the two main conformers of RBK21 with the loop 256 in either an upward or downward conformation (black arrow). c) Sequence Logo of the clade of 3D7 KIR2DL1-binding RIFINs from, generated using WebLOGO60 with numbering from 142 of RBK21. d) Shannon-entropy of sequence conservation was calculated using the Protein Variability Server (PVS57). Residues with entropy <0.8 are shown as sticks and coloured with dark green for 0, mid-green for 0–0.5 and light green for 0.5–0.8. e) Competition of RIFINs was measured by SPR analysis. 100% represents the binding of KEN-01 at 10 μM to a KIK2DL1 coated surface. This was repeated in the presence of a non-inhibitory nanobody (Nb1) or by other RIFINs indicated. Error bars show ± SD from n = 3 technical replicates. f) Plotting all polymorphisms found in the D1 and D2 domains of KIR2DL1, as found in the IPD-KIR database. Orange sticks denote the residue is mutated in more than one of the 177 recorded allotypes, yellow sticks denote a polymorphism found in only one recorded allotype. g) The effect of the V111F allotype of KIR2DL1 on RBK21 binding was measured by SPR analysis, in both cases with 500 RU on the chip and a concentration series of 12 doubling dilutions starting at 50 µM.
