Here is a question from my colleague Dr. Jeanine Walenga at Loyola University Medical Center in Chicago:
Dear George, Is there data on whether beta-2-glycoprotein 1 (β2GP1) interferes in the serotonin release assay (SRA) for heparin-induced thrombocytopenia (HIT) testing?
Hello, Jeanine, and thank you for your question, which drove me to the books, PubMed, and ultimately to Dr. Jon Geske senior R&D scientist at Precision BioLogic Inc. Here is Jon’s response:
Hi, George. I am not aware of any studies that suggest that β2GP1 interferes with the SRA test. I found one paper (Nimpf et al. Atherosclerosis 1987;103: 109–14) that suggested that β2GP1 inhibited serotonin release induced by ADP, but platelet activation in HIT is through the Fc gamma receptor.
If I find anything else, I will be sure to let you know. Jon
I did find one additional reference that supports Jon’s conclusion: Shi W, Chong BH, Chesterman CN. Beta 2-glycoprotein I is a requirement for anticardiolipin antibodies binding to activated platelets: differences with lupus anticoagulants. Blood 1993; 81:1255–62. This article was published right around the time we were learning about the role of β2GP1 in the anti-cardiolipin antibody reaction system. The authors make this statement in their abstract: “In neither case does LA nor ACA have an effect on thrombin-induced release of serotonin or beta-thromboglobulin nor do they affect platelet aggregation induced by a number of agonists. This antibody binding may play an etiological role in thrombocytopenia associated with aPL, but does not explain thrombosis on the basis of hyperaggregability or increased platelet release.”
Here is the Shi article. I hope this helps, and if there is anyone out there who has additional information, please comment below.