Molecular cloning and radioligand binding characterization of the chemokine receptor CCR5 from rhesus macaque and human.
The aim of this study was to determine if macaque represents a suitable species for the pre-clinical evaluation of novel CCR5 antagonists, such as maraviroc (UK-427,857). To do this we cloned and expressed CCR5 from rhesus macaque and compared the binding properties of [125I]-MIP-1beta and [3H]-maraviroc with human recombinant CCR5. [125I]-MIP-1beta bound with similar high affinity to CCR5 from macaque (K(d) = 0.24 +/- 0.05 nM) and human (K(d) = 0.23 +/- 0.05 nM) and with similar kinetic properties. In competition binding studies the affinity of a range of human chemokines for macaque CCR5 was also similar to human CCR5. Maraviroc inhibited binding of [125I]-MIP-1beta to CCR5 from macaque and human with similar potency (IC50 = 17.50 +/- 1.24 nM and 7.18 +/- 0.93 nM, respectively) and antagonised MIP-1beta induced intracellular calcium release mediated through CCR5 from macaque and human with similar potency (IC50 = 17.50 +/- 3.30 nM and 12.07 +/- 1.89, respectively). [3H]-maraviroc bound with high affinity to CCR5 from macaque (K(d) = 1.36+/-0.07 nM) and human (K(d) = 0.86 +/- 0.08 nM), but was found to dissociate approximately 10-fold more quickly from macaque CCR5. However, as with the human receptor, maraviroc was shown to be a high affinity, potent functional antagonist of macaque CCR5 thereby indicating that the macaque should be a suitable species in which to evaluate the pharmacology, safety and potential mechanism-related toxicology of novel CCR5 antagonists.
Napier
Carolyn
C
Discovery Biology, Pfizer Global Research and Development, Sandwich Laboratories, Sandwich, Kent. CT13 9NJ UK. carolyn.napier@pfizer.com
Sale
Harriet
H
Mosley
Michael
M
Rickett
Graham
G
Dorr
Pat
P
Mansfield
Roy
R
Holbrook
Mark
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D002460:Cell Line; D054407:Chemokine CCL4; D003001:Cloning, Molecular; D003510:Cyclohexanes / Q000378:metabolism; D017931:DNA Primers; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D008253:Macaca mulatta; D019402:Macrophage Inflammatory Proteins / Q000378:metabolism; D000077592:Maraviroc; D008969:Molecular Sequence Data; D011869:Radioligand Assay; D019713:Receptors, CCR5 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014230:Triazoles / Q000378:metabolism; D014316:Tritium
D054407:Chemokine CCL4; D003510:Cyclohexanes; D017931:DNA Primers; D007457:Iodine Radioisotopes; D019402:Macrophage Inflammatory Proteins; D019713:Receptors, CCR5; D011994:Recombinant Proteins; D014230:Triazoles; D014316:Tritium; D000077592:Maraviroc