title: Human plasma membrane-derived vesicles inhibit the phagocytosis of apoptotic cells--possible role in SLE.
abstract: Plasma membrane-derived vesicles (PMVs) also known as microparticles, are small membrane-bound vesicles released from the cell membrane via blebbing and shedding. PMVs have been linked with various physiological functions as well as pathological conditions such as inflammation, autoimmune disease and cardiovascular disease. PMVs are characterised by the expression of phosphatidylserine (PS) on the plasma membrane. PS, also expressed on apoptotic cells (ACs) enables macrophages to phagocytose ACs. As it is widely known that PMV production is increased during apoptosis, we were able to show that PMVs could compete dose dependently with ACs for the PS receptor on macrophages, so reducing phagocytosis of ACs. In a clinical setting this may result in secondary necrosis and further pathological conditions. In SLE in which there are raised PMV levels, there is an anti-phospholipid-mediated increase in PMV release, which can be abrogated by depletion of IgG. Our work provides an insight into how PMVs may play a role in the aetiology of autoimmune disease, in particular SLE.
authors.affiliation: Cellular and Molecular Immunology Research Centre, School of Human Sciences, Faculty of Life Sciences, London Metropolitan University, 166-220 Holloway Road, London N7 8DB, UK.
authors.forename: Samuel
authors.initials: S
authors.lastname: Antwi-Baffour
authors.forename: Sharad
authors.initials: S
authors.lastname: Kholia
authors.forename: Yushau K-D
authors.initials: YK
authors.lastname: Aryee
authors.forename: Ephraim A
authors.initials: EA
authors.lastname: Ansa-Addo
authors.forename: Dan
authors.initials: D
authors.lastname: Stratton
authors.forename: Sigrun
authors.initials: S
authors.lastname: Lange
authors.forename: Jameel M
authors.initials: JM
authors.lastname: Inal
mesh_terms: D017152:Antibodies, Antiphospholipid / Q000276:immunology; D017209:Apoptosis / Q000276:immunology*; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology*; D055252:Cell-Derived Microparticles / Q000276:immunology*; D006801:Humans; D019169:Jurkat Cells; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D010587:Phagocytosis
chemical_list: D017152:Antibodies, Antiphospholipid