Table 3

Effect of antibodies on 7EFC O-deethylase and reference activities in human liver microsomes

Human Liver SampleAntibody7EFC O-Deethylase ActivityReference AssayReference Assay Activity
% %
HLS2MAB-2A680Coumarin 7-hydroxylase 18
HLS9MAB-2A6108Coumarin 7-hydroxylase 14
HLS5MAB-2E188 p-Nitrophenol hydroxylase 10
HLS6MAB-2E167 p-Nitrophenol hydroxylase 10
HLS5Anti-CYP1A256PhenacetinO-deethylase 8
HLS9Anti-CYP1A2100PhenacetinO-deethylase 8
HLS5Anti-CYP2C1389Diclofenac 4′-hydroxylase 15
HLS5Anti-CYP2C1389(S)-Mephenytoin 4′-hydroxylase 22

7EFC O-deethylase (5 μM substrate), phenacetinO-deethylase (200 μM substrate), diclofenac 4′-hydroxylase (100 μM substrate), (S)-mephenytoin 4′-hydroxylase (100 μM substrate), p-nitrophenol hydroxylase (50 μM substrate), and coumarin 7-hydroxylase (200 μM substrate) activities were assayed as described in Materials and Methods.Antibodies were used as described in Materials and Methods.Values shown are the means of two determinations and represent the percentage of activity in the absence of anti-CYP antibodies.