Cellular Imaging Core

Joe Trask, Head, Cellular Imaging Core

High Content Imaging

The technologies known as High Content Screening (HCS), High Content Analysis (HCA),  High Content Imaging (HCI) and Image Cytometry represent the convergence of several established and mature technologies, including an automated confocal or wide-field based microscopy platform, with detectors such as digital cameras or photomultiper tubes (PMT), robotics, and computer hardware to capture, store, and retrieve digitized images for computer assisted image analysis.   Data generation includes tens to hundreds of measurements per cell describing morphology, intensity, distribution, and location of fluorescent markers and probes at the cellular and sub-cellular levels to predict or measure outcome of biological responses following chemical or drug treatment.  Phenotypic characterization such as cell transduction measurements, including protein redistribution within cellular compartments, protein phosphorylation and transcription changes, receptor internalization, cell spreading and motility of cells, dendritic extensions and synaptogenesis, cell cycle and DNA content analysis, cell health, viability, and toxicological indicators are made in high throughput automated fashion.  Data generated from these HCS phenotypic measurements to study and identify rare cells within heterogeneous populations, live cell kinetic responses, and three-dimensional in vitro and ex-vivo models have led to significant advances in our understanding of the cellular processes involved in toxicology, development, and underling diseases such as cancer, metabolic diseases, and neurodegeneration. Specimens for these high content screening and analysis programs include live or fixed endpoint assays using immortalized cell lines, stem cells, primary cells and ex vivo and intact tissue; or small organisms such as round worm (Caenorhabditis elegans), fruit fly (Drosophila), and Zebrafish (Cyprinidae).  One challenge with current in vitro predictive cell toxicity testing is that viability is typically the only parameter measured and more subtle perturbations in cell physiology go undetected.

The Hamner’s High Content Imaging Core uses high throughput confocal microscopy and a variety of fluorescent probes to detail subtle changes in cell physiology to detect potential mechanisms of toxicity. Hamner Investigators can then use this data to obtain mechanistic insight into the hepatotoxic potential of certain compounds.

At the Hamner's Cellular Imaging Core, we utilize these High Content Screening approaches by incorporating a variety of fluorescent probes on individual cells to measure spatial interactions within cells and signaling pathways, including detailed subtle changes in cell physiology, in order to detect potential mechanisms of underlying cellular toxicity. By automating capture and analysis of high resolution images of cells, this technology can assess the hepatotoxic potential of compounds in routine cell culture assay conditions from hundreds to thousands of test wells per day. Moreover, this approach provides mechanistic insight by identifying perturbations in cellular organelles and physiological processes. These observations can be linked to specific pathways through parallel analysis of the transcriptome and metabolome or by compound profiling correlations. Joe Trask, the current President of the Society of Biomolecular Imaging and Informatics and a leader in this field, oversees all cellular imaging work at The Hamner Institutes for Health Sciences.