Developing specific fibrinogen blockers based on GPIIb/IIIa ligand binding sites or sequences complementary to RGD is reviewed as an alternative strategy for thrombus prevention.
Specific fibrinogen blockers may offer an alternative method for thrombus prevention by acting at the final step of platelet aggregation without intrinsically activating the GPIIb/IIIa receptor.
Activation of the platelet surface receptor GPIIb/IIIa is the final pathway of platelet aggregation, regardless of the initiating stimulus. RGD analogues, peptidomimetics and monoclonal antibodies to GPIIb/IIIa have been developed targeting the blockage of the receptor and inhibition of the fibrinogen binding. However, the intrinsic activating effect of GPIIb/IIIa blockers is widely discussed as one potential contributing factor for the disappointing outcome of trials with GPIIb/IIIa inhibitors. An alternative method for thrombus prevention could be the use of specific fibrinogen blockers since they will act at the final step of the platelet aggregation and are expected to leave the receptor unaffected. To achieve this target the design of the fibrinogen ligands could be based on (i) sequences derived from GPIIb/IIIa ligand binding sites, and (ii) sequences complementary to RGD and/or to fibrinogen gamma-chain. The available information, which could be used as a starting point for developing potent fibrinogen ligands, is reviewed.
Vassilios Tsikaris (Fri,) conducted a review in Thrombus prevention. Fibrinogen ligands/blockers was evaluated. Developing specific fibrinogen blockers based on GPIIb/IIIa ligand binding sites or sequences complementary to RGD is reviewed as an alternative strategy for thrombus prevention.