Factors stabilizing formed platelet aggregates. The intercellular space between aggregating platelets facilitates interaction between integrins and their ligands and other adhesion molecules, and promotes activation of Eph receptor kinases by cell surface ephrins. This narrow space also provides a protective environment for the accumulation of soluble agonists (ADP, thrombin, and TXA2), Gas-6, and the proteolytically shed exodomains of platelet surface proteins (GPIb, P-selectin, sCD40L).