Cell Xpress ™ Cell Line Optimization Service Using Laser-Enabled Analysis and Processing (LEAP ™ ) Technology Angela M. Davis, Genova A. Richardson, Nan Lin, Jennifer R. Cresswell, Matthew V. Caple and Kevin J. Kayser Cell Sciences and Development, SAFC Biosciences 2909 Laclede Avenue, Saint Louis, MO 63103, USA 04707 0078 Introduction to Cell Xpress SAFC Biosciences (SAFCB) Cell Xpress technology combines in situ imaging with laser manipulation to identify, select, and monitor expansion of high recombinant protein secreting clones. Cell Xpress provides significant advantages over microscope-based platforms with respect to throughput, robustness, and automation. Cell Xpress enables rapid analysis of relative secretion heterogeneity and purification of transfected or clonal populations. The Cell Xpress technology, when combined with SAFCB medium, feed, and process optimization, can result in a significant increase in productivity from cell culture-based processes. SAFCB uses this integrated process development platform to develop media and feed for use in the production of a cell culture-derived therapeutic protein from our customers. SAFCB employs Cell Xpress to analyze secretion heterogeneity of an initial cell population which may be either a clonal cell line or a transfected pool. The initial population is laser processed to enrich the population for high producing cells by eliminating low or non-producing cells in the population. Following two to three rounds of enrichment, single cell clones are generated from the enriched pool. Clones and enriched populations are then expanded and screened for growth and productivity performance. The LEAP Instrument The LEAP Instrument and the Proprietary C-lect ™ 384-Well Plate Methods Method Comparison: Cell Xpress vs. Traditional Cell Line Generation Allows for a more cost-effective and efficient process More cells from initial population evaluated Labor -intensive expansion efforts focused on higher producers Cell Xpress Cell Line Generation Secretion Assay Cloning Expansion Traditional Cell Line Generation Cloning Expansion Secretion Assay Secretion Assay Cloning Expansion Cloning Expansion Secretion Assay Cell Xpress combines in situ analysis of individual cell secretion with laser-mediated elimination of poorly-secreting cells Applications Laser Enrichment of A Transfected “Pool” Population Transfected Pool Cell Xpress Enriched Transfected Pool Normalized Secretion Area Average Intensity Transfected Pool Cell Xpress Enriched Transfected Pool Normalized Secretion Area Average Intensity Normalized Secretion Area Average Intensity (Binned) Normalized Secretion Area Average Intensity (Binned) Single Cell Clone Characterization and Selection Correlation of Maximum Volumetric Productivity vs. Normalized Secretion Area Average Intensity A B C Normalized Secretion A B C A B C A B C Normalized Secretion The Benefits of Cell Xpress • Cell Xpress yields higher secreting cell lines faster – Process 30,000+ clones per single plate – In situ verification of protein secretion prior to labor-intensive clone expansion efforts • Provides visual documentation of clones – Image-based validation of clonality and automated tracking of clonal outgrowth – Documentation package Acknowledgements Erika Holroyd, Kathy Roeder Schematic Illustration: Cell XpressCapture and Detection In situ detection of secreted recombinant IgG: Fluorescent-labeled detection reagent detects secreted rIgG (red); live cells are stained with viable cell stain (green). Quantitative Measurement of Clone Secretion Secretion Area Average Intensity (SAAI) Secretion Area Average Intensity (SAAI) 04707 Cresswell LEAP Poster.indd 1 04707 Cresswell LEAP Poster.indd 1 7/8/2008 7:09:34 AM 7/8/2008 7:09:34 AM