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hERG, temperature & pharmacology
Ion Channel Retreat Vancouver August 9 - 11 2017
Anders Lindquist
Distributor Sophion Direct Sales Office
Sales Office/demo lab Boston, MA USA
Sophion Headquarters, R&D, TS &
Manufacturing Copenhagen, Denmark
Sales Office Shanghai, China
Sales Office/demo lab Tokyo, Japan
Location Total Head Count
Copenhagen, Denmark 44
Tokyo, Japan 4
Shanghai, China 1
Boston, USA 6
Cambridge, UK 1
Total 56
Global Company with Local Reach
2
Why hERG
3
Kannankeril et al. Pharmacolog Rev 2010
hERG pharmacology?
4 Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Hardly the exciting NKOTB anymore • Center stage for safety screening
and for the CiPA initiative. • hERG pharmacology is a complex
function of voltage protocol, temeprature, solutions and other factors.
.
IC50 cisapride as f(VP, T, ...) Milnes et al. JPTM, 2010
QUBE Automated patch-clamp system
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• 384 well instrument w/ 384 amplifiers
• Voltage-gated, ligand-gated and current clamp recordings
• Combine freely in the same experiment
• Temperature control • Both heat and cool
• Unattended operation and up to 18.000 wells tested/day
• Single or multi-hole micro-fluidic consumables
QChip 384
6
Individual electrode pairs for each well
Ensure stable recordings over a long period of time
Instantly ready for experiments
Maintenance free
Liquid interface from the top
Electronic interface from the bottom
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Qube Temperature Control
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Control Unit
Temperature Unit Biochip Interface
Pump
Sensor Heating/ cooling system
hERG tail current vs temperature
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Plate-view of standard protocol currents
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20C
34C 31C
25C
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Steady-state activation
9
Temperature V1/2 (mV)
20 8.7
25 1.3
31 -4.6
34 -11
20C
34C
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Activation cont’d
10
Temperature tau (ms)
20 820
25 320
31 100
34 50
20C
34C
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Steady-state inactivation
11
20C
34C
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Temperature V½ (mV)
20 -52
25 -44
31 -37
34 -28
Pharmacology
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Quinidine 10 µM @ 25 C
Astemizole Bepridil
Quinidine Verapamil
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
Astemizole 41 nM @ 25 C
Temp. (C) IC50 (µM)
20 0.008
25 0.008
Temp. (C) IC50 (µM)
20 0.25
25 0.18
Temp. (C) IC50 (µM)
20 1.2
25 1.5
Temp. (C) IC50 (µM)
20 0.51
25 0.44
Verapamil Quinidine
Pharmacology
13 Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
hERG and temperature
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• No simple yes and no answer but depends on the circumstances there are temperature dependent compounds but a minority? longer protocols tend to decrease temperature-dependent potency difference.
Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017
• Possible to run temperature controlled testing on routine basis • Find other primerary drivers for your project than ”just” potency
Milnes et al. JTPM, 2010
Click to edit Master subtitle style
Thank you!
Questions?
15
Acknowledgements Mette Christensen Pia Andersen Daniel Sauter Mads Korsgaard Rasmus Jacobsen Melanie Schupp Weifeng Yu
Structure by Wang et al.
16
Cryo-EM Structure of the Open Human Ether-a-go-go-Related K+ Channel hERG Wang W, MacKinnon R Cell (2017) 169 p.422-430
Inactivation and recovery from inactivation
17 Anders Lindqvist Ion Channel Retreat Vancouver August 9 - 11 2017