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Isolation of Labile Multi-protein Complexes by in vivo Controlled Cellular Cross-Linking and Immuno-magnetic Affinity Chromatography
Published on: March 9, 2010
CD9 antigen is an accessory subunit of the VLA integrin complexes
E Rubinstein1, F Le Naour, M Billard
1INSERM U268, Hôpital Paul Brousse, Villejuif, France.
European Journal of Immunology
|December 1, 1994
Summary
The CD9 antigen, a tetraspanin, associates with beta 1 integrins in specific cell lines. This interaction influences cell aggregation and migration, suggesting distinct functional mechanisms.
Area of Science:
- Cell Biology
- Immunology
- Molecular Biology
Background:
- The CD9 antigen is a tetraspanin family member with an undefined role.
- Integrins are crucial cell surface receptors involved in cell adhesion and signaling.
Purpose of the Study:
- To investigate the association between the CD9 antigen and beta 1 integrins.
- To elucidate the functional consequences of this association on cell behavior.
Main Methods:
- Co-precipitation and Western blotting to detect protein interactions.
- Co-capping experiments to assess molecular colocalization.
- Functional assays including cell adhesion, aggregation, and migration (Transwell chambers).
Main Results:
- CD9 antigen associates with beta 1 integrins (VLA-4, VLA-5) in NALM-6 and HEL cell lines.
- The association is primarily with the beta 1 chain, not specific integrin subtypes.
- CD9 and anti-VLA monoclonal antibodies induce cell aggregation and inhibit migration.
- Aggregation and migration inhibition appear to be mediated by different pathways.
Conclusions:
- CD9 antigen interacts with beta 1 integrins, influencing cell aggregation and migration.
- The functional outcomes of CD9-integrin association are complex and involve distinct mechanisms.
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