To examine whether enhanced in vivo proteolysis of von Willebrand factor (vWF) would account for the reported loss of larger multimers in acute thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), we studied eight patients with acute TTP/HUS whose blood samples were collected into an anticoagulant containing a cocktail of protease inhibitors to impede in vitro proteolysis. In all, enhanced proteolytic degradation of vWF was expressed as a relative decrease in the intact 225-Kd subunit of vWF and a relative increase in the 176-Kd fragment. However, instead of the loss of larger forms of normal multimers reported by other investigators, the plasma of all but one of our patients (whether they had TTP or HUS) contained a set of larger than normal (supranormal) multimers. Hence, although proteolytic fragmentation of vWF was enhanced during acute TTP/HUS, this phenomenon was not associated with the loss of larger multimers. In the five patients who survived the acute disease and underwent plasma exchange (three with HUS and two with chronic relapsing TTP), subunits and fragments returned to normal values, and supranormal multimers were no longer detected in plasma. In conclusion, even though vWF proteolysis is enhanced in acute TTP/HUS, it does not lead to loss of larger multimers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.