Primary Screening of a 1564 Compound Focused Diversity set Against the Human Cardiac Sodium Channel Nav1.5 Using the IonWorks Quattro System
Poster Nov 07, 2005
James Costantin, Shawn Handran, David Yamane, Naibo Yang
Population Patch Clamp™ (PPC) technology was recently introduced byMolecular Devices in the IonWorks™ Quattro system. PPC records from up to 64 cells at a time, and greatly reduces biological variability, achieving nearly 100% success rates and highly consistent data quality (Z’-Factors between 0.6 – 0.8). We conducted a feasibility study for using the IonWorks Quattro system in a primary screen of a focused library (1564 compounds) for modulators of the cardiac sodium channel Nav1.5 (hH1) –an important target for anti-arrhythmia therapeutics.
The screen was carried out in duplicate at a single concentration (10 uM) in less than two working days. There were 37 actives with 50% or more inhibition identified (2.4% hit rate), which were all followed-up for potency (10-point dose-response run in duplicate) and selectivity (counter screened against Kv1.3). A number of compounds show use dependence and selectivity.
This rapid assay campaign demonstrates that the IonWorks Quattro system can be used for directed primary screens of voltage-gated ion channel modulators. The daily throughput of the IonWorks Quattro is >2000 data points per day. It is estimated that a 10,000 compound single-point screen with follow-up pharmacology could be completed in approximately 2-4 working weeks.