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Updated: Jul 19, 2026
09:14
Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
Annexin-1 modulates T-cell activation and differentiation
Fulvio D'Acquisto1, Ahmed Merghani, Emilio Lecona
1William Harvey Research Institute, Bart's and The London, Queen Mary School of Medicine and Dentistry, UK. f.dacquisto@qmul.ac.uk
Blood
|September 30, 2006
Summary
Annexin-1, an anti-inflammatory protein, modulates T-cell receptor signaling and adaptive immunity. This protein enhances T-cell activation and promotes Th1 cell differentiation, suggesting its role in autoimmune diseases.
Area of Science:
- Immunology
- Molecular Biology
Background:
- Annexin-1 is known for its anti-inflammatory effects in innate immunity.
- Its role in adaptive immunity and T-cell modulation remained unexplored.
Purpose of the Study:
- To investigate the potential role of Annexin-1 in adaptive immunity.
- To explore Annexin-1's function in T-cell activation and differentiation.
Main Methods:
- Stimulation of T cells with anti-CD3/CD28 in the presence of Annexin-1.
- Analysis of T-cell activation markers (CD25, CD69) and proliferation.
- Assessment of transcription factor activation (NF-kappaB, NFATs, AP-1).
- T-cell differentiation studies and collagen-induced arthritis model in mice.
- Analysis of Annexin-1 expression in rheumatoid arthritis patient samples.
Main Results:
- Annexin-1 augmented T-cell activation, proliferation, and expression of CD25 and CD69.
- Annexin-1 increased NF-kappaB, NFATs, and AP-1 activation, preceded by T-cell receptor (TCR)-induced Annexin-1 receptor externalization.
- Annexin-1 promoted Th1 cell differentiation and exacerbated collagen-induced arthritis in mice.
- Elevated Annexin-1 expression was observed in CD4+ T cells from rheumatoid arthritis patients.
Conclusions:
- Annexin-1 acts as a molecular tuner of TCR signaling, influencing adaptive immunity.
- Annexin-1 may play a role in autoimmune diseases characterized by Th1/Th2 imbalance or aberrant T-cell activation.
- Annexin-1 represents a potential therapeutic target for T-cell-mediated pathologies.
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