Antiphosphatidylserine antibodies in patients with autoimmune diseases and HIV-infected patients: Effects of Tween 20 and relationship with antibodies to β2-glycoprotein I

• Published in: Journal of clinical laboratory analysis Vol. 13; no. 2; pp. 59 - 64
• Main Authors: González, Concepción, Lestón, Antonio, García-Berrocal, Belén, Sánchez-Rodriguez, Angel, Martín-Oterino, José A., Alberca, Ignacio, Cordero, Miguel, Jorge, Ramón, Navajo, José A., González-Buitrago, José M.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 1999
• Subjects: anti β2 glycoprotein antibodies; anticardiolipin antibodies; antiphosphatidylserine antibodies; autoimmune diseases; HIV infection; Original
• ISSN: 0887-8013; 1098-2825
• DOI: 10.1002/(SICI)1098-2825(1999)13:2<59::AID-JCLA3>3.0.CO;2-Q

Antiphospholipid antibodies (aPL) react with negatively charged phospholipids, which may often be complexed with a protein cofactor such as β2 glycoprotein (β2GPI) and prothrombin. Cofactor requirements may be assessed by measuring antibodies to β2GPI or by adding Tween 20 to some reagents in the assays for aPL (anticardiolipin and antiphosphatidylserine). We have measured anticardiolipin antibodies (aCL), antiphosphatidylserine antibodies (aPS), and anti β2 glycoprotein antibodies (aβ2GPI) in the serum of 10 normal subjects, 20 patients with systemic autoimmune diseases (SAD) diagnosed as having systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS), and 12 patients with HIV infection. Adding Tween 20 to aPS, the assay couldn't differentiate protein cofactor dependent from independent antibodies, but this can be done by measuring aβ2GPI (P = 0.0008). There was a significant correlation between aCL and aβ2GPI in the control group and in the patients with SAD, but not in the HIV‐positive (HIV+) patients. After excluding the HIV+ patients, the best Spearman correlation was obtained between aβ2GPI and aCL (0.64, P < 0.0005). In 3 out of 7 patients with positive aβ2GPI and in 5 out of 6 patients with moderate or high positive aCL of the group of SAD, there was a history of venous thrombosis. The presence of moderate or high values of aCL either alone or together with aβ2GPI was significantly associated with a history of venous thrombosis (P < 0.05). Moderate or high aCL concentrations and their association with aβ2GPI seems to be useful for the assessment of the risk of venous thrombosis in unselected patients with SLE or APS. J. Clin. Lab. Anal. 13:59–64, 1999. © 1999 Wiley‐Liss, Inc.