The CD42b (HIP1) antibody recognizes a heterodimer glycoprotein (GPIb?) that contains an ? chain (CD42Bovine, 145 kDa) and a (B) chain (CD42c, 22 kDa) linked by a disulfide bond forming a noncovalent comple, Xenopus/Amphibian, with CD42a (GPI, Xenopus/Amphibian,) and d. CD42b antigen is e, Xenopus/Amphibian,pressed on platelets and megakaryocytes. The GPIb/I, Xenopus/Amphibian, comple, Xenopus/Amphibian, (CD42a-d) serves as a receptor for von Willebrand Factor (vWF) and thrombin, and mediates adhesion of platelets to subendothelium of damaged vascular walls. The absence of the CD42 comple, Xenopus/Amphibian, leads to the Bernard-Soulier Syndrome (BSS). The CD42b (HIP1) antibody inhibits the ristocetin-dependent binding of vWF to platelets, ristocetin-induced platelet agglutination, and partially inhibits collagen-induced aggregation.