Hamostaseologie 2002; 22(01): 18-28
DOI: 10.1055/s-0037-1622004
Original Article
Schattauer GmbH

Methoden zur Bestimmung des Faktors XIII/XIIIa

Methods for the determination of factor XIII/XIIIa
M. Wilmer
1   Pentapharm Ltd., Abteilung F&E Hömostase und Test-Kit-Entwicklung (Laborleitung: Dr. rer. nat. Marianne Wilmer), Basel
,
V. Schröder
2   Thromboselabor, Departement Klinische Forschung (Laborleitung: Prof. Dr. phil. nat. André Haeberli) Universität Bern, Inselspital, Schweiz
,
H. P. Kohler
2   Thromboselabor, Departement Klinische Forschung (Laborleitung: Prof. Dr. phil. nat. André Haeberli) Universität Bern, Inselspital, Schweiz
› Author Affiliations
Further Information

Publication History

Publication Date:
29 December 2017 (online)

Zusammenfassung

Aktivierter Blutgerinnungsfaktor XIII (FXIIIa), eine Transglutaminase, quervernetzt in der letzten Phase der Sekundärhämostase die Fibrinpolymere durch Bildung intermolekularer Amidbindungen zwischen Glutaminund Lysinresten zu einem komplex strukturierten, dreidimensionalen Gerinnsel. Die dadurch gesteigerte Gerinnselfestigkeit wird durch den kovalenten Einbau von Zytoskelettbestandteilen wie Aktin und Myosin weiter erhöht. Darüber hinaus schützt der FXIIIa-abhängige Einbau antifibrinolytisch wirkender Faktoren wie α2-Antiplasmin und Thrombin-aktivierbarer Fibrinolyseinhibitor (TAFI) vor vorzeitiger Lyse des Gerinnsels. Die kovalente Vernetzung der Fibrinpolymere mit Adhäsionsproteinen der extrazellulären Matrix (z. B. Fibronektin, Kollagen, Vitronektin, von-Willebrand-Faktor) fixiert das Gerinnsel am Ort der Gefäßläsion und unterstützt den Regenerationsprozess des Gewebes. Diese vielfältigen Funktionen von FXIIIa zeigen seine zentrale Bedeutung in der Hämostase. Im vorliegenden Übersichtsartikel werden Tests zur Erfassung der funktionellen Aktivität, Konzentration und zur Identifizierung des FXIII-Val34Leu-Polymorphismus vorgestellt.

Summary

Activated factor XIII (FXIIIa) plays an important role in the final stage of the coagulation cascade by covalent crosslinking of fibrin strands. As a transglutaminase FXIIIa catalyses the generation of intermolecular amide bonds between lysine and glutamine residues resulting in a complex three-dimensional clot structure. Enhanced clot stability is supported by covalent binding of cytosceleton factors like actin and myosin. Moreover, the clot is protected against premature lysis by the incorporation of fibrinolysis inhibitors like α2-antiplasmin and thrombin activatable fibrinolysis inhibitor (TAFI). A covalent crosslinking of the fibrin strands with extracellular matrix proteins like fibronectin, vitronectin, collagen and von Willebrand factor (vWF) immobilizes the clot at the site of injury. Moreover FXIII supports the healing process of damaged tissue. In this review assays for determination of FXIIIa activity, FXIII concentration and identification of the FXIIIVal34Leu polymorphism are shown.

 
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