title: Phagocytic clearance of electric field induced 'apoptosis-mimetic' cells.
abstract: Cells undergoing apoptosis lose lipid asymmetry that is often manifested by the exposure of phosphatidylserine (PS) to the outer surface of the cell membrane. Macrophages and other cell types recognize externalized PS to signal phagocytosis, thereby eliciting a non-inflammatory response. PS exposure is obligatory in the recognition and clearance of apoptotic cells. Here, we find that externally applied moderate electric field induces PS externalization in a mouse B-cell (FOX-NY) membrane without procaspase-3 activation, a major characteristic of apoptotic cells. The field-induced PS inversion is caused as a result of electroporation and/or a process involving membrane reorganizations and recovery that ensues following field exposure. Using a mouse macrophage cell line (J7444A.1) from the same strain, we show phagocytic clearance of PS expressing B-cells and demonstrate that this is in part due to the apoptosis mimicry of the field exposed cells.
authors.affiliation: The Center for Biochemistry & Biophysics, Laboratory of Biochemistry, NHLBI NIH, Building 50, Room 2127, 50 South Drive, Bethesda, MD 20892-8012, USA. ephrem@helix.nih.gov
authors.forename: E
authors.initials: E
authors.lastname: Tekle
authors.forename: M D
authors.initials: MD
authors.lastname: Wolfe
authors.forename: H
authors.initials: H
authors.lastname: Oubrahim
authors.forename: P B
authors.initials: PB
authors.lastname: Chock
mesh_terms: D000818:Animals; D017209:Apoptosis; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D004560:Electricity; D051379:Mice; D010587:Phagocytosis; D010718:Phosphatidylserines / Q000378:metabolism*
chemical_list: D010718:Phosphatidylserines
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