Evaluation of Cell Membrane Expression of Annexin A2 on Monocytes by Flow Cytometry in Primary Antiphospholipid Syndrome

Not Applicable

Recruiting

• Conditions: Antiphospholipid Syndrome
• Interventions: Biological: blood withdrawal

• Registration Number: NCT06373926
• Lead Sponsor: Centre Hospitalier Universitaire, Amiens

Brief Summary

Annexin A2 (ANXA2), an endothelial cell receptor for plasminogen and tissue plasminogen activator, plays a pivotal role in regulation of fibrinolysis in vitro and in vivo and has been identified as a new autoantigen in antiphospholipid syndrome (APS). ANXA2 can exist as a monomer or a heterotetrameric complex with S100A10 protein. The aim of this study was to evaluate the cell membrane expression of ANXA2 on circulating monocytes in APS by flow cytometry. Several pathogenic mechanisms are involved in APS such as activation of endothelial cells, platelets and monocytes, inhibition of the natural anticoagulant protein C/protein S pathway, activation of the complement system and also impairment of fibrinolysis. Annexin A2 which hits binding partner S100A10, ANXA2 forms a cell surface complex that regulates generation of plasmin. ANXA2 is involved in the pathogenesis of APS-associated through several possible mechanisms. Human peripheral blood monocytes represent the major circulating ANXA2-expressing cell and ANXA2-mediated assembly of plasminogen and tissue activator of plasminogen (tPA) on monocyte/macrophages contributes to plasmin generation. Thus the investigators could suppose that decrease of cell membrane expression of ANXA2 on circulating monocytes represent a new pathogenic mechanism in APS.

Detailed Description

Not available

Study Timeline

• Study Start: 2023-03-28
• Status Verified: 2024-04
• Study First Submitted: 2024-04-09
• Study First Submitted QC: 2024-04-16
• Last Update Submitted: 2024-04-16
• Study First Posted: 2024-04-18
• Last Update Posted: 2024-04-18
• Primary Completion: 2025-03
• Study Completion: 2025-03

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• APS patients who fulfilled the revised criteria for APS

Exclusion Criteria

• Patients less than 18 years old
• Solid and hematological malignancies
• Other autoimmune diseases
• Cirrhosis

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
case	blood withdrawal	APS patients
control	blood withdrawal	healthy individuals

Primary Outcome Measures

Name	Time	Method
Cell membrane expression rate of ANXA2 on circulating monocytes in APS	1 hour

Secondary Outcome Measures

Name	Time	Method
cell membrane expression of ANXA2 and S100A10 in APS patients	1 hour
Cellular expression of ANXA2 and S100A10 in APS patients	1 hour

Trial Locations

Locations (1)

CHU Amiens; 🇫🇷 Amiens, France