title: Antibodies against the N-terminal domain of annexin A2 in antiphospholipid syndrome.
abstract: Annexin A2 (ANXA2, an endothelial cell receptor for plasminogen and tissue plasminogen activator) has been identified as a new autoantigen in antiphospholipid syndrome (APS). The aim of the present study was to evaluate the presence of antibodies against the N-terminal domain of annexin A2 (ANXA2) in primary APS (PAPS). By using a synthetic peptide corresponding to the 31N-terminal amino acids of ANXA2 (ANXA2(N31)) as an antigen, we performed an enzyme-linked immunosorbent assay (ELISA) to measure anti-ANXA2(N31) IgG and IgM antibodies in the serum of PAPS patients (n=19), systemic lupus erythematosus (SLE) patients (n=50) and healthy blood donors (n=106). We did not find any statistically differences between the three groups in terms of IgG and IgM anti-ANXA2(N31) titres. Elevated IgG anti-ANXA2(N31) titres were not observed in the serum of PAPS or SLE patients who had previously tested positive for anti-ANXA2 antibodies. Thus, the ANXA2 N-terminal domain does not appear to be the target antigen for anti-ANXA2 antibodies in APS.
authors.affiliation: Department of Internal Medicine, Amiens University Hospital, Amiens, France. salle.valery@chu-amiens.fr
authors.forename: V
authors.initials: V
authors.lastname: Salle
authors.forename: J C
authors.initials: JC
authors.lastname: Mazière
authors.forename: A
authors.initials: A
authors.lastname: Brulé
authors.forename: J
authors.initials: J
authors.lastname: Schmidt
authors.forename: A
authors.initials: A
authors.lastname: Smail
authors.forename: P
authors.initials: P
authors.lastname: Duhaut
authors.forename: C
authors.initials: C
authors.lastname: Mazière
authors.forename: R
authors.initials: R
authors.lastname: Makdassi
authors.forename: G
authors.initials: G
authors.lastname: Choukroun
authors.forename: F
authors.initials: F
authors.lastname: Betsou
authors.forename: J P
authors.initials: JP
authors.lastname: Ducroix
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017306:Annexin A2 / Q000276:immunology*; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000276:immunology; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: C472822:ANXA2 protein, human; D017306:Annexin A2; D001323:Autoantibodies; D001324:Autoantigens; D007074:Immunoglobulin G; D007075:Immunoglobulin M