ANTICARDIOLIPIN WET WORKSHOP REPORT - 5TH INTERNATIONAL-SYMPOSIUM ON ANTIPHOSPHOLIPID ANTIBODIES

An anticardiolipin wet workshop was conducted at the Fifth Internation al Antiphospholipid Symposium (San Antonio, Texas, September 9-12, 199 2). The workshop had four objectives: 1. to determine variability in m easurement of immunoglobulin (Ig) G, IgM, and IgA anticardiolipin of e ight unknown sera; 2. to examine the correlation between three commerc ial enzyme-linked immunosorbent assay (ELISA) kits and the Antiphospho lipid Standardization Laboratory; 3. to examine protocols by which ant icardiolipin binding to phospholipid antigens and beta(2)glycoprotein 1 (beta(2)GP1) might be compared; and 4. to examine the beta(2)GP1 eff ects on cardiolipin binding activity. Results showed good overall corr elation of quantitative anticardiolipin measurements between workshop participants and the Antiphospholipid Standardization Laboratory. Corr elation with individual ELISA kits was also good. With respect to the third objective, all participants showed comparable binding to cardiol ipin and phosphatidylserine but none to phosphatidylcholine or beta(2) GP1. Finally, beta(2)GP1 enhanced, but was not essential for, anticard iolipin binding. This workshop will not settle controversies about ant icardiolipin measurement and specificity, but suggests protocols to re solve these issues.