biostudies-literatureHesketh EEKidney Research UKe0131849https://www.ebi.ac.uk/biostudies/studies/S-EPMC4488261biostudies-literatureUnknown10(6)Autoimmunity is associated with defective phagocytic clearance of apoptotic cells. IgM deficient mice exhibit an autoimmune phenotype consistent with a role for circulating IgM antibodies in apoptotic cell clearance. We have extensively characterised IgM binding to non-apoptotic and apoptotic mouse thymocytes and human Jurkat cells using flow cytometry, confocal imaging and electron microscopy. We demonstrate strong specific IgM binding to a subset of Annexin-V (AnnV)+PI (Propidium Iodide)+ apoptotic cells with disrupted cell membranes. Electron microscopy studies indicated that IgM+AnnV+PI+ apoptotic cells exhibited morphologically advanced apoptosis with marked plasma membrane disruption compared to IgM-AnnV+PI+ apoptotic cells, suggesting that access to intracellular epitopes is requirePloS oneCirculating IgM Requires Plasma Membrane Disruption to Bind Apoptotic and Non-Apoptotic Nucleated Cells and Erythrocytes.PMC4488261ST4/2011Kluth DCHesketh EEHughes JDransfield IfalseCirculating IgM Requires Plasma Membrane Disruption to Bind Apoptotic and Non-Apoptotic Nucleated Cells and Erythrocytes.Autoimmunity is associated with defective phagocytic clearance of apoptotic cells. IgM deficient mice exhibit an autoimmune phenotype consistent with a role for circulating IgM antibodies in apoptotic cell clearance. We have extensively characterised IgM binding to non-apoptotic and apoptotic mouse thymocytes and human Jurkat cells using flow cytometry, confocal imaging and electron microscopy. We demonstrate strong specific IgM binding to a subset of Annexin-V (AnnV)+PI (Propidium Iodide)+ apoptotic cells with disrupted cell membranes. Electron microscopy studies indicated that IgM+AnnV+PI+ apoptotic cells exhibited morphologically advanced apoptosis with marked plasma membrane disruption compared to IgM-AnnV+PI+ apoptotic cells, suggesting that access to intracellular epitopes is require2015-01-01T00:00:00Z20152025-06-01T01:35:39.42Z2019-03-26T23:33:30ZS-EPMC44882612612163910.1371/journal.pone.0131849