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Published on: November 23, 2016
Some antiphospholipid antibodies inhibit phospholipase A2 activity
A E Schorer1, P G Duane, V L Woods
1Department of Medicine, Minneapolis Veterans' Affairs Medical Center, MN 55417.
The Journal of Laboratory and Clinical Medicine
|July 1, 1992
Summary
Antiphospholipid antibodies reduce vascular prostacyclin production by inhibiting phospholipase A2 (PLA2) activity. This antibody-mediated inhibition affects key pathways in thrombosis and inflammation.
Area of Science:
- Immunology
- Vascular Biology
- Biochemistry
Background:
- Antiphospholipid antibodies are linked to arterial thrombosis and reduced vascular prostacyclin production.
- The mechanism by which these antibodies affect prostacyclin synthesis remains under investigation.
Observation:
- Purified antiphospholipid antibodies inhibited phospholipase A2 (PLA2) activity in vitro and in a defined system.
- Endothelial cells treated with patient-derived immunoglobulin showed impaired prostacyclin generation and reduced arachidonate release.
- Thrombin-induced platelet-activating factor synthesis was also inhibited, paralleling the reduction in prostacyclin generation.
Findings:
- Antiphospholipid antibodies directly inhibit endothelial phospholipase A2 (PLA2) activity.
- Phosphatidylcholine, a precursor for prostacyclin and platelet-activating factor, is a target.
- Inhibition of PLA2 by antiphospholipid antibodies does not require additional cofactors.
Implications:
- This study elucidates a key mechanism linking antiphospholipid antibodies to thrombotic events.
- Understanding this antibody-PLA2 interaction could lead to novel therapeutic strategies for antiphospholipid syndrome.
- The findings highlight PLA2 as a potential therapeutic target in managing antibody-mediated vascular complications.
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