RT Journal Article
SR Electronic
T1 Selective and Potent Inhibition of Human CYP2C19 Activity by a Conformationally Targeted Antipeptide Antibody
JF Drug Metabolism and Disposition
JO Drug Metab Dispos
FD American Society for Pharmacology and Experimental Therapeutics
SP 715
OP 717
VO 28
IS 7
A1 Timothy Schulz-Utermoehl
A1 Richard J. Mountfield
A1 Kjeld Madsen
A1 Peer N. Jørgensen
A1 Kristian T. Hansen
YR 2000
UL http://dmd.aspetjournals.org/content/28/7/715.abstract
AB A conformationally targeted anti-peptide antibody was produced by immunizing a rabbit with a cyclized peptide corresponding to a loop region of human CYP2C19 (residues 250–261). In an enzyme-linked immunosorbent assay, the antibody bound strongly to recombinant CYP2C19 and poorly to recombinant CYP2C8, CYP2C9, and CYP2C18. In immunoblotting studies, the antibody bound strongly to recombinant CYP2C19 and weakly to recombinant CYP2C8. No binding to recombinant CYP1A2, CYP2C9, CYP2C18, CYP2D6, CYP2E1, and CYP3A4 was detected. In immunoinhibition experiments, the anti-peptide antibody targeted against CYP2C19 potently inhibited (S)-mephenytoin 4′-hydroxylase activity of human hepatic microsomal fraction (>90%). It had no appreciable effect on ethoxyresorufinO-deethylase (CYP1A2), tolbutamide methyl-hydroxylase (CYP2C9), dextromethorphan O-demethylase (CYP2D6), 4-nitrophenol hydroxylase (CYP2E1), or testosterone 6β-hydroxylase (CYP3A4) activity of human hepatic microsomal fraction. However, large amounts of purified IgG fractions were able to inhibit up to 35% of paclitaxel 6α-hydroxylase (CYP2C8) activity. In conclusion, we have demonstrated that an anti-peptide antibody targeted against residues 250 to 261 of human CYP2C19 selectively and potently inhibited CYP2C19 activity of human hepatic microsomal fraction. The American Society for Pharmacology and Experimental Therapeutics