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bioRxiv · 10.1101/2020.06.11.147140

Localized cell-surface sampling of a secreted factor using cell-targeting beads

van Neel, T. L.·Berry, S. B.·Berthier, E.·Theberge, A. B.
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Abstract

Intercellular communication through the secretion of soluble factors plays a vital role in a wide range of biological processes (e.g., homeostasis, immune response), yet identification and quantification of many of these factors can be challenging due to their degradation or sequestration in cell culture media prior to analysis. Here, we present a customizable bead-based system capable of simultaneously binding to live cells (through antibody-mediated cell-tethering) and capturing cell-secreted molecules. Our functionalized beads capture secreted molecules (e.g., hepatocyte growth factor secreted by fibroblasts) that are diminished when sampled via traditional supernatant analysis techniques (p < 0.05), effectively rescuing reduced signal in the presence of neutralizing components in the cell culture media. Our system enables capture and analysis of molecules integral to chemical communication that would otherwise be markedly decreased prior to analysis. For Table of Contents Only O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/147140v2_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@17fbf42org.highwire.dtl.DTLVardef@1e5b810org.highwire.dtl.DTLVardef@972783org.highwire.dtl.DTLVardef@1a32eb0_HPS_FORMAT_FIGEXP M_FIG C_FIG

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van Neel, T. L., Berry, S. B., Berthier, E., Theberge, A. B.. 2020-06-12. Localized cell-surface sampling of a secreted factor using cell-targeting beads. https://doi.org/10.1101/2020.06.11.147140

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