Yannick Gansemans

An echistatin-like arg-gly-asp (rgd)-containing sequence in the heavy-chain cdr3 of a murine monoclonal-antibody that inhibits human platelet glycoprotein iib/iiia function

We describe the production and biochemical characterization of the first GPIIb/IIIa‐inhibiting monoclonal antibody that contains an RGD sequence in the CDR3 region of the heavy chain. Monoclonal antibodies obtained by immunizing mice with human platelets were screened using consecutive ELISAs based on human platelets and immunoaffinity‐purified glycoprotein (GP) IIb/IIIa coated on microtitre plates. Out of 30 monoclonal antibodies reacting with GPIIb/IIIa, one, MA‐16N7C2, potently inhibited platelet aggregation induced by ADP, thrombin, arachidonic acid, collagen, U46619, adrenaline and platelet‐activating factor, whereas ristocetin‐induced aggregation was unaffected.