Fibrinogen signal transduction in the nervous system


Katerina Akassoglou, Gladstone Institute of Neurological Disease, University of California, San Francisco, 1650 Owens St, San Francisco, CA 94158, USA.
Tel.: +1 415 734 2512; fax: +1 415 355 0824.


Summary.  Fibrinogen is a pleiotropic blood protein that regulates coagulation, inflammation and tissue repair. Fibrinogen extravasates in the nervous system after injury or disease associated with vascular damage or blood–brain barrier (BBB) disruption. Fibrinogen is not merely a marker of BBB disruption, but plays a causative role in neurologic disease as a potent inducer of inflammation and an inhibitor of neurite outgrowth. Fibrinogen mediates functions in the nervous system as a ligand for cell-specific receptors. In microglia, fibrinogen mediates activation of Akt and Rho via the CD11b/CD18 integrin receptor, while in neurons fibrinogen induces phosphorylation of epidermal growth factor (EGF) receptor via the αvβ3 integrin. Pharmacologic targeting of the interactions of fibrinogen with its nervous system receptors could provide novel strategies for therapeutic intervention in neuroinflammatory and neurodegenerative diseases.