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Updated: Apr 2, 2026
09:14
Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
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Integrin modulating factor-1: a lipid that alters the function of leukocyte integrins
A Hermanowski-Vosatka1, J A Van Strijp, W J Swiggard
1Rockefeller University, New York, New York 10021.
Cell
|January 24, 1992
Summary
Researchers discovered integrin modulating factor (IMF-1), a molecule that controls CR3 integrin avidity in immune cells. IMF-1
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Integrin CR3 (CD11b/CD18) avidity can change without altering cell surface receptor numbers.
- Leukocyte adhesion and migration are regulated by integrin function.
- Understanding the mechanisms controlling integrin avidity is crucial for immune response research.
Purpose of the Study:
- To identify and characterize the molecule responsible for regulating CR3 integrin avidity.
- To elucidate the role of this molecule in polymorphonuclear leukocyte (PMN) activation and adhesion.
Main Methods:
- Biochemical analysis of a novel molecule, integrin modulating factor (IMF-1).
- Assays measuring CR3 integrin binding activity in response to IMF-1.
- Analysis of IMF-1 levels in PMNs during cellular stimulation.
Main Results:
- A novel molecule, integrin modulating factor (IMF-1), was identified as a controller of CR3 avidity.
- IMF-1 addition enhanced ligand binding to purified CR3 and PMNs.
- Cell stimulation led to a transient increase in IMF-1, correlating with CR3 activity.
Conclusions:
- PMNs regulate adhesivity by controlling the synthesis of IMF-1, an allosteric activator of leukocyte integrins.
- IMF-1 is an acidic, amphiphilic molecule containing a carbon-carbon double bond, likely an unsaturated fatty acid or isoprenoid acid.
- This finding provides a new mechanism for the dynamic regulation of immune cell adhesion.
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