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Updated: Aug 14, 2026
09:14
Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
The FX enzyme is a functional component of lymphocyte activation
1Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel.
Cellular Immunology
|February 8, 2002
Summary
The FX enzyme, crucial for fucose biosynthesis, is upregulated in activated T and B cells, impacting selectin ligand expression and lymphocyte extravasation.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Fucose is vital for selectin ligands, which mediate leukocyte-endothelial cell interactions during extravasation.
- The FX enzyme catalyzes the final step in GDP-L-fucose biosynthesis.
- Previous work showed outside-in signaling regulates FX in cancer cells.
Purpose of the Study:
- To investigate the role and regulation of the FX enzyme in lymphocytes.
- To determine if FX influences selectin ligand expression in activated T and B cells.
Main Methods:
- Polyclonal activation of T and B cells.
- Measurement of FX enzyme and selectin ligand (sLe-x, CLA) expression.
- Treatment with FX antisense oligonucleotides in activated T cells.
Main Results:
- Polyclonal activation significantly increased FX enzyme and selectin ligand expression in T and B cells.
- FX antisense oligonucleotides reduced selectin ligand expression in activated T cells.
- Demonstrated FX regulation by outside-in signals in lymphocytes.
Conclusions:
- FX enzyme expression is regulated by outside-in signals in lymphocytes.
- FX is involved in the biosynthesis of selectin ligands in lymphocytes.
- FX likely plays a role in the extravasation of activated lymphocytes.
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