title: Minimized cell usage for stem cell-derived and primary cells on an automated patch clamp system.
abstract: BACKGROUND
  Chip-based automated patch clamp systems are widely used in drug development and safety pharmacology, allowing for high quality, high throughput screening at standardized experimental conditions. The merits of automation generally come at the cost of large amounts of cells needed, since cells are not targeted individually, but randomly positioned onto the chip aperture from cells in suspension. While cell usage is of little concern when using standard cell lines such as CHO or HEK cells, it becomes a crucial constraint with cells of limited availability, such as primary or otherwise rare and expensive cells, like induced pluripotent stem (IPS) cell-derived cardiomyocytes or neurons.
  
  
  METHODS
  We established application protocols for CHO cells, IPS cell-derived neurons (iCell® Neurons, Cellular Dynamics International), cardiomyocytes (Cor.4U®, Axiogenesis) and pancreatic islet cells, minimizing cell usage for automated patch clamp recordings on Nanion's Patchliner. Use of 5 μl cell suspension per well for densities between 55,000 cells/ml and 400,000 cells/ml depending on cell type resulted in good cell capture.
  
  
  RESULTS
  We present a new cell application procedure optimized for the Patchliner achieving>80% success rates for using as little as 300 to 2000 cells per well depending on cell type. We demonstrate that this protocol works for standard cell lines, as well as for stem cell-derived neurons and cardiomyocytes, and for primary pancreatic islet cells. We present recordings for these cell types, demonstrating that high data quality is not compromised by altered cell application.
  
  
  CONCLUSIONS
  Our new cell application procedure achieves high success rates with unprecedentedly low cell numbers. Compared to other standard automated patch clamp systems we reduced the average amount of cells needed by more than 150 times. Reduced cell usage crucially improves cost efficiency for expensive cells and opens up automated patch clamp for primary cells of limited availability.
authors.affiliation: Nanion Technologies GmbH, Gabrielenstraße 9, 80636 Munich, Germany. nadine@nanion.de
authors.forename: Nadine
authors.initials: N
authors.lastname: Becker
authors.forename: Sonja
authors.initials: S
authors.lastname: Stoelzle
authors.forename: Sven
authors.initials: S
authors.lastname: Göpel
authors.forename: David
authors.initials: D
authors.lastname: Guinot
authors.forename: Patrick
authors.initials: P
authors.lastname: Mumm
authors.forename: Claudia
authors.initials: C
authors.lastname: Haarmann
authors.forename: Daniela
authors.initials: D
authors.lastname: Malan
authors.forename: Heribert
authors.initials: H
authors.lastname: Bohlen
authors.forename: Eugen
authors.initials: E
authors.lastname: Kossolov
authors.forename: Ralf
authors.initials: R
authors.lastname: Kettenhofen
authors.forename: Michael
authors.initials: M
authors.lastname: George
authors.forename: Niels
authors.initials: N
authors.lastname: Fertig
authors.forename: Andrea
authors.initials: A
authors.lastname: Brüggemann
mesh_terms: D000818:Animals; D001331:Automation; D016466:CHO Cells / Q000166:cytology; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology*; D007515:Islets of Langerhans / Q000166:cytology; D051379:Mice; D032383:Myocytes, Cardiac / Q000166:cytology*; D009474:Neurons / Q000166:cytology*; D018408:Patch-Clamp Techniques / Q000191:economics / Q000379:methods*
keywords: Automated patch clamp; Patchliner; pancreatic islet cells; primary cells; stem cell-derived cardiomyocytes; stem cell-derived neurons