Stains
Integrins
Copyright: 2002-2018, PathologyOutlines.com, Inc.
PubMed Search: Integrins [title]
Integrins
Author: Nat Pernick, M.D.
Topic Completed: 1 June 2005
Minor changes: 6 March 2019
Copyright: 2002-2018, PathologyOutlines.com, Inc.
PubMed Search: Integrins [title]
Cite this page: Pernick N. Integrins. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsintegrins.html. Accessed June 7th, 2020.
Definition / general
- Family of adhesion proteins with various functions, including major cell surface receptors for extracellular matrix proteins
- Membrane glycoprotein heterodimer complexes that are assembled by noncovalent association of alpha and beta subunits, with active and inactive states; currently are 18 alpha subunits and 8 beta subunits, which combine to form 24 different integrins
- Alpha subunit has extracellular domain that binds matrix molecules; beta subunit has cytoplasmic domain that interacts with actin cytoskeleton, microfilament-associated proteins and signaling mediators
- Functions:
- Homing of progenitor T cells to thymus
- Differentiation and proliferation of B and T cells in bone marrow, transcription of genes involved in cell-cell contacts and endothelial cell migration
- Activated by intracellular bacteria and by extracellular ligand binding
- Inhibited by RGD (arginine-glycine-aspartic acid) sequence, which blocks integrins from binding to ligands
See also
-
Integrin alpha 2b beta 3
- General:
- Also called glycoprotein IIa / IIIb, fibrinogen receptor
- Platelet integrin that induces platelet aggregation
- Antibodies to alpha2b beta3 prevent ischemia of percutaneous coronary angioplasty
- General:
- Fibrinogen forms cross links with this platelet receptor during platelet aggregation
- General:
- See CD49d
- General:
- Also called CD29, fibronectin receptor
- Supports assembly of fibronectin matrix
- General:
- Have role in tumor cell migration and invasion in vitro
- Reduced expression in invasive bladder CA
- Principal ligand is laminin-5 protein (component of epithelial basement membrane)
- Protein production is characteristic of basal / myoepithelial type of breast carcinoma
- Beta4 subunit is only expressed in combination with alpha 6 subunit
- Additional references:
- General:
- Specifically expressed in endothelial cells of newly formed blood vessels
- May play a role in central nervous system neoplasms
- Positive staining - disease:
- CNS tumors (particularly ependymomas, Hum Pathol 2005;36:665)
- General:
- See CD18
Integrin alpha 3 beta 2
Integrin alpha 4 beta 1
Integrin alpha 5 beta 1
Integrin alpha 4 beta 1
Integrin alpha v beta 3
Integrin beta 2
