Discussion

The Human Induced Pluripotent Stem Cell Initiative (HipSci), funded by the Wellcome Trust and Medical Research Council (MRC), focuses on the generation and characterisation of hundreds of induced pluripotent stem (iPS) cell lines. These come from both healthy individuals and patients with selected diseases and will become an open resource for the scientific community, bringing together clinical genetics with data on genomics, proteomics and cell biology. At King’s College London, the HipSci Cell Phenotyping group evaluates and quantifies responses of these cells to chemical, physical and biological stimuli using novel assays and artificial microenvironments. We have developed a 96-well format assay exposing iPS cells to varying concentrations of fibronectin. Cells are imaged in real-time using an IncuCyte ZOOM (Essen Biosciences), fixed for end-point analysis after 24 hours and imaged with an Operetta device (Perkin Elmer). Our read-out is based on DAPI, EdU to identify proliferating cells, and CellMask to label the cellular plasma membrane. This allows phenotypes such as cell density, morphological features and proliferation to be detected, as well as complex cell-to-cell behaviour (e.g. clumping). Importantly, phenotypes can be quantified, compared and collated with genomic data. Here we present preliminary data obtained from a panel of over 50 iPS cell lines derived from healthy individuals. This approach is proving useful to benchmark healthy iPS cell lines and will likely be of great value in the future to establish relevant assays for disease modeling and drug discovery.