Antibodies to phospholipid-binding plasma proteins and occurrence of thrombosis in patients with systemic lupus erythematosus.
There is accumulating evidence that anti-phospholipid (aPL) antibodies in the sera of patients with autoimmune diseases bind to a complex of anionic phospholipids and plasma phospholipid-binding proteins, namely beta 2-glycoprotein I (beta 2-GPI) and prothrombin. It has been suggested that a conformational change in beta 2-GPI, induced by binding either to anionic phospholipids or to the oxygen molecules on the irradiated microtiter plate, reveals cryptic antigenic epitope(s) in the native protein. We used an enzyme-linked immunoassay for measuring antibodies against two phospholipid-binding proteins, i.e., beta 2-GPI and prothrombin, absorbed to an irradiated plate in an unselected series of 139 patients with systemic lupus erythematosus (SLE). Elevated levels of antibodies against beta 2-GPI were found in 49% of patients and antibodies against prothrombin in 34% of patients. Both antibodies were significantly associated with deep venous thrombosis in patients with SLE (P = 0.009 for both antibodies). Accordingly, testing of these antibodies seems to be clinically useful in evaluating the risk of thrombosis.
Puurunen
M
M
Department of Immunobiology, National Public Health Institute, Helsinki, Finland.
Vaarala
O
O
Julkunen
H
H
Aho
K
K
Palosuo
T
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017153:Antibodies, Anticardiolipin / Q000097:blood; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D001053:Apolipoproteins / Q000276:immunology; D005260:Female; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000150:complications / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011516:Prothrombin / Q000276:immunology; D013927:Thrombosis / Q000097:blood / Q000209:etiology / Q000276:immunology*; D053482:beta 2-Glycoprotein I
D017153:Antibodies, Anticardiolipin; D017152:Antibodies, Antiphospholipid; D001053:Apolipoproteins; D006023:Glycoproteins; D016682:Lupus Coagulation Inhibitor; D053482:beta 2-Glycoprotein I; D011516:Prothrombin