Effects of antiphospholipid antibodies on in vitro platelet aggregation

Palatinus, A.A., Ahuja, K.D.K. and Adams, M.J.ORCID: 0000-0002-7743-4515 (2012) Effects of antiphospholipid antibodies on in vitro platelet aggregation. Clinical and Applied Thrombosis/Hemostasis, 18 (1). pp. 59-65.

Abstract

Antiphospholipid antibodies contribute to the development of thrombosis, although precise mechanisms remain to be elucidated. We determined the effects of affinity-purified anti-beta2-glycoprotein 1 (anti-β2GP1) and anti-prothrombin (anti-PT) antibodies on in vitro platelet aggregation. Adenosine diphosphate (ADP) and collagen-induced platelet aggregation were performed using platelet-rich plasma ([PRP] 250 × 109/L). Antiphospholipid antibodies (1.25-10 μg/mL) were preincubated with PRP for 10 minutes at 37°C prior to the addition of agonist. Anti-β2GP1 antibodies significantly reduced platelet aggregation (percentage area under the curve; %AUC) in a concentration-dependent manner using both 5 μmol/L (P < .001) and 2.5 μmol/L (P = .038) ADP but did not significantly affect the rate of aggregation. Anti-PT antibodies significantly enhanced 5 µg/mL collagen-induced platelet aggregation (%AUC; P = .034) but did not affect ADP-induced platelet aggregation. These results suggest (1) interactions and effects of antiphospholipid antibodies on platelets are agonist and concentration dependent and (2) anti-β2GP1 antibodies may inhibit dense granule release and/or inhibition of the arachidonic acid pathway.

Item Type:	Journal Article
Publisher:	SAGE Publications
Copyright:	© The Author(s) 2012
URI:	http://researchrepository.murdoch.edu.au/id/eprint/53630

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