1 May 1998 Measurement of receptor cross-linking at the cell surface via multiparameter flow cytometry
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Proceedings Volume 3256, Advances in Optical Biophysics; (1998) https://doi.org/10.1117/12.307056
Event: BiOS '98 International Biomedical Optics Symposium, 1998, San Jose, CA, United States
Many cellular responses, particularly in the immune system, are triggered by ligand binding to a cell-surface receptor. However, as indicated by bell-shaped dose-response curves, ligand binding alone is sometimes insufficient to trigger a response. Often, ligand binding must also induce the aggregation of cell-surface receptors through crosslinking, which occurs when a ligand binds simultaneously to two or more receptors. Thus, an important goal in cell biology has been to establish quantitative relationships between the amount of ligand present on a cell surface and the number of crosslinked ligand-specific cell-surface receptors. To better understand ligand-induced receptor aggregation, we have been investigating the binding of a model multivalent antigen (DNP25PE) to cell-surface anti-DNP FITC-labeled IgE (FITC- IgE). To determine the kinetic and equilibrium parameters that characterize crosslinking in this system, we have developed a combined theoretical and experimental approach that is based on multiparameter flow cytometry. With this approach, we can measure both the average number of ligand molecules that are bound per cell and the average number of receptor binding sites that are bound per cell. The average number of DNP25PE per cell is determined by measuring the fluorescence of phycoerythrin. The average number of occupied IgE sites per cell is determined by measuring the fluorescence of FITC, which is quenched upon ligand binding. This novel approach, together with conventional methods for changes in intracellular calcium, allows us to correlate for the first time the dynamics of IgE crosslinking with cell activation.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Richard G. Posner, Richard G. Posner, Jennifer Bold, Jennifer Bold, Yael Bernstein, Yael Bernstein, Joe Rasor, Joe Rasor, Joshua Braslow, Joshua Braslow, William S. Hlavacek, William S. Hlavacek, Alan S. Perelson, Alan S. Perelson, } "Measurement of receptor cross-linking at the cell surface via multiparameter flow cytometry", Proc. SPIE 3256, Advances in Optical Biophysics, (1 May 1998); doi: 10.1117/12.307056; https://doi.org/10.1117/12.307056

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