Assay Method Information

Assay Name:  ATX Assay
Description:  Reagents LPC (oleoyl (18:1)) was purchased from Avanti Polar Lipids (Alabaster, Ala.) and solubilized in methanol to 20 mM. Amplex Red was obtained from Invitrogen Life Technologies (Paisley, UK) and dissolved in DMSO to 10 mM. Choline oxidase and horseradish peroxidase (HRP) were obtained from Sigma Aldrich (Dorset, UK) and dissolved in HBSS to 20 U/ml and 200 U/ml respectively. All reagents were stored at −20° C. in single use aliquots. All experimental measurements were performed in assay buffer made up immediately prior to use (HBSS, 0.01% BSA essentially fatty acid free).Protein Recombinant human ATX was prepared at Novartis (Basel, CH) in a human embryonic kidney (HEK) cell preparation, and stored in single use aliquots of 26 mg/ml (26 μM) stocks stored at −80° C.Method All experimental measurements were performed in black 384 well polystyrene (low volume, round bottom, Corning (3676)) plates. PerkinElmer EnVision (Fluorescence Intensity/Absorbance Monochromator) or Tecan Infinite 200 PRO series plate reader was used to detect change in fluorescent intensity.Assessing ATX inhibition ATX activity was determined by measurement of released choline in reactions containing ATX (10 nM), choline oxidase (0.1 U/ml), HRP (100 U/ml), amplex red (50 μM) and LPC 18:1 (10 μM). Compounds of the invention were prepared as 10 point serial dilutions from 1 μM in duplicate and pre-incubated with ATX at 37° C. for 20 minutes prior to the addition of remaining reagents. The liberated choline was measured from changes in fluorescence intensity (λex 530 nm, λem 590 nm) of the product resurofin at 37° C. every 2 minutes over a 40-minute period. ATX activity was measured as a slope of the linear portion of the progress curve, typically between 14 to 24 minutes.Data analysis Slope data was exported to Graphpad prism (Graphpad software, San Diego, Calif.)
Affinity data for this assay
 

If you find an error in this entry please send us an E-mail