Retraction: Thrombin-mediated feedback activation of factor XI on the activated platelet surface is preferred over contact activation by factor XIIa or factor Xia. VOLUME 275 (2000) PAGES 20514-20519

Abstract

Thrombin-mediated Feedback Activation of Factor XI on the Activated Platelet Surface Is Preferred over Contact Activation by Factor XIIa or Factor XIaJournal of Biological ChemistryVol. 275Issue 27PreviewTo study the pathways for initiation of intrinsic blood coagulation, activated human platelets were compared with dextran sulfate as surfaces for factor XI activation by factor XIIa, factor XIa, or thrombin. Activated gel-filtered platelets promoted the activation of factor XI (60 nm) by thrombin (0.02–10 nm, EC50 ∼100 pm, threshold concentration ∼10 pm) at initial rates 2- to 3-fold greater than those obtained with dextran sulfate in the presence of either high molecular weight kininogen (45 nm) and ZnCl2 (25 μm) or prothrombin (1.2 μm) and CaCl2 (2 mm). Full-Text PDF Open Access RETRACTION PAGES 20514-20519: The authors are retracting the entire article for the following reasons. All of the authors with the exception of F. A. Baglia retract the paper listed above because recent experiments conducted by Dipali Sinha, Sergei Shikov, Wenman Wu, and Syed Ahmad in the laboratory of Peter N. Walsh failed to confirm the conclusion that activated platelets promote the activation of factor XI by thrombin. A detailed explanation of the chronology of events leading to this retraction and to the retraction of a paper from Biochemistry (Baglia, F. A., and Walsh, P. N. (1998) Prothrombin is a cofactor for the binding of factor XI to the platelet surface and for platelet-mediated factor XI activation by thrombin. Biochemistry 37 2271-2281) has been published in the journal Biochemistry (manuscript bi-2007-01501k, accepted July 27, 2007). We apologize to the readers, reviewers, and editors of the Journal of Biological Chemistry for publishing these erroneous data.