Figure 3.
Relative sizes of high-affinity ligands of the CCR5 chemokine receptor. 873140 is a synthetic small-molecule (0.6 kDa) non-competitive allosteric antagonist. MIP-1α(8 kDa) is a natural peptide
ligand for the receptor. The viral envelope protein gp120 (120 kDa) mediates the interaction between CCR5 and HIV.