The modulation of platelet adhesion and activation by chitosan through plasma and extracellular matrix proteins

Chitosan has been shown to promote initial wound closure events to prevent blood loss. Platelet adhesion and activation are crucial early events in these processes after traumatic bleeding leading to thrombus formation. Platelet adhesion to chitosan was found to be enhanced in the presence of adsorbed plasma and extracellular matrix proteins and was found to be primarily mediated by αIIbβ3 integrins, while α2β1 integrins were found to be involved in platelet adhesion to collagen and perlecan. Platelets were found to be activated by chitosan, as shown by an increase in the expression of αIIbβ3 integrins and P-selectin, while the extent of activation was modulated by the presence of proteins including perlecan and fibrinogen. Collagen-coated chitosan was found to activate platelets to the same extent as either chitosan or collagen alone. These data support the role of plasma and extracellular matrix proteins in promoting chitosan mediated platelet adhesion and activation supporting the hypothesis that chitosan promotes wound healing via these interactions.

► We investigated platelet adhesion to chitosan pre-adsorbed with plasma or extracellular matrix proteins.
► Platelet adhesion to chitosan was enhanced in the presence of adsorbed plasma and extracellular matrix proteins.
► Platelets bound to perlecan coated chitosan through integrin α2β1.
► Chitosan activated platelets, while the extent of activation was modulated by the presence of proteins.