Apoptosis, annexin a5 and anti-Annexin a5 antibodies in the antiphospholipid syndrome

Abstract

It has been proposed that apoptosis is one of the mechanisms involved in the generation of antiphospholipid antibodies. The presence of antiphospholipid antibodies is the main laboratory criterion for a definite diagnosis of the antiphospholipid syndrome. Annexinopathies are disorders characterized by deregulation of annexins expression levels and function. Annexin A5 has been used as an agent for molecular imaging techniques (visualization of phosphatidylserine-expressing apoptotic cells) in vitro and in vivo in animal models and in patients (injection of human recombinant anxA5 into the patient's circulation). Although the determination of titers of anti-annexin A5 antibodies is not mandatory for the diagnosis of the antiphospholipid syndrome, it was reported that patients with primary antiphospholipid syndrome with a history of recurrent abortions had elevated titers of anti-annexin A5 antibodies, while the presence of thromboses was not associated with elevated levels of these antibodies.