title: Antibodies to endothelial cells and to beta 2-glycoprotein I in the antiphospholipid syndrome: prevalence and isotype distribution.
abstract: The aim of this study was to analyse the prevalence and isotype distribution of antibodies to endothelial cells (aEC) and to beta 2-glycoprotein I (a beta 2GPI) in the antiphospholipid syndrome (APS). Fifteen patients with an APS [nine associated with systemic lupus erythematosus (SLE) and six "primary'] and 15 with SLE without an APS were prospectively studied. The aEC were determined by an enzyme-linked immunosorbent assay (ELISA) using endothelial cells derived from human umbilical vein and the a beta 2GPI by ELISA using highly purified beta 2GPI. A positive titre of aEC was detected in 20 out of 30 patients (67%), but in none of the control group. Ten patients had both IgG and IgM isotypes, five had IgG only and five had only IgM. Thirteen patients with the APS (87%) were found to have a positive titre of aEC, while only seven with SLE but without a history of APS (47%) had aEC (P < 0.05). Nine patients with the APS (60%) had a positive titre of a beta 2GPI (four had both IgG and IgM isotypes, one had IgG only and four had only IgM), while none of the patients without an APS (0%) had these antibodies (P < 0.001). A significant association was also found between the presence of aPL and aEC (P < 0.05), as well as between aPL and a beta 2GPI (P < 0.001). Both aEC and a beta 2GPI can be found in the APS. This reinforces the theory that APS represents a complex autoimmune disorder in which several autoantibodies co-exist with aPL.
authors.affiliation: Systemic Autoimmune Diseases Unit, Hospital Clinic, Barcelona, Catalonia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Navarro
authors.forename: R
authors.initials: R
authors.lastname: Cervera
authors.forename: M
authors.initials: M
authors.lastname: Teixidó
authors.forename: J C
authors.initials: JC
authors.lastname: Reverter
authors.forename: J
authors.initials: J
authors.lastname: Font
authors.forename: A
authors.initials: A
authors.lastname: López-Soto
authors.forename: J
authors.initials: J
authors.lastname: Monteagudo
authors.forename: G
authors.initials: G
authors.lastname: Escolar
authors.forename: M
authors.initials: M
authors.lastname: Ingelmo
mesh_terms: D000328:Adult; D017153:Antibodies, Anticardiolipin / Q000097:blood; D017152:Antibodies, Antiphospholipid / Q000097:blood; D016736:Antiphospholipid Syndrome / Q000276:immunology* / Q000378:metabolism; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D002478:Cells, Cultured; D015331:Cohort Studies; D004727:Endothelium / Q000166:cytology / Q000276:immunology*; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000032:analysis* / Q000097:blood; D007231:Infant, Newborn; D008180:Lupus Erythematosus, Systemic / Q000276:immunology / Q000378:metabolism; D008297:Male; D053482:beta 2-Glycoprotein I
chemical_list: D017153:Antibodies, Anticardiolipin; D017152:Antibodies, Antiphospholipid; D001323:Autoantibodies; D006023:Glycoproteins; D007132:Immunoglobulin Isotypes; D053482:beta 2-Glycoprotein I