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

NCT06373926 | Recruiting

• 1 other identifier: PI2019_843_0010
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

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.

Conditions

Antiphospholipid Syndrome

Keywords

annexin A2; antiphospholipid syndrome; monocytes

Outcome Measures

Primary Outcomes (1)

• Cell membrane expression rate of ANXA2 on circulating monocytes in APS

  1 hour

Secondary Outcomes (2)

• Cellular expression of ANXA2 and S100A10 in APS patients

  1 hour

• cell membrane expression of ANXA2 and S100A10 in APS patients

  1 hour

Study Arms (2)

case

EXPERIMENTAL

APS patients

Biological: blood withdrawal

control

ACTIVE COMPARATOR

healthy individuals

Biological: blood withdrawal

Interventions

blood withdrawal BIOLOGICAL

blood withdrawal

case; control

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• APS patients who fulfilled the revised criteria for APS

You may not qualify if:

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

Sponsors & Collaborators

• Centre Hospitalier Universitaire, Amiens: lead

Study Sites (1)

CHU Amiens

Amiens, 80054, France

RECRUITING

MeSH Terms

Conditions

Antiphospholipid Syndrome

Condition Hierarchy (Ancestors)

Autoimmune Diseases; Immune System Diseases

Central Study Contacts

Valéry Salle, MD

CONTACT

03 22 66 82 30; salle.valery@chu-amiens.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 9, 2024
• First Posted: April 18, 2024
• Study Start: February 5, 2025
• Primary Completion: March 1, 2026
• Study Completion: March 1, 2026
• Last Updated: November 19, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)