DiaPharma Group, Inc.

Number and/or name

Function

I (fibrinogen)

forms clot (fibrin)

II (prothrombin)

its active form (IIa) activates I, V, VII, XIII, protein C, platelets

Tissue factor

co-factor of VIIa (formerly known as factor III)

Calcium

required for coagulation factors to bind to phospholipid (formerly known as factor IV)

V (proaccelerin, labile factor)

co-factor of X with which it forms the prothrombinase complex

VI

unassigned - old name of Factor Va

VII (stable factor)

activates IX, X

VIII (antihemophilic factor)

co-factor of IX with which it forms the tenase complex

IX (Christmas factor)

activates X: forms tenase complex with factor VIII

X (Stuart-Prower factor)

activates II: froms prothrombinase complex with factor V

XI (plasma thromboplastin antecedent)

activates XII, IX and prekallikrein

XII (Hageman factor)

activates prekallikrein and fibrinolysis

XIII (fibrin-stabilizing factor)

crosslinks fibrin

von Willebrand factor

binds to VIII, mediates platelet adhesion

prekallikrein

activates XII and prekallikrein; cleaves HMWK

high molecular weight kininogen (HMWK)

supports reciprocal activation of XII, XI, and prekallikrein

fibronectin

mediates cell adhesion

antithrombin III

inhibits IIa, Xa, and other proteases;

heparin cofactor II

inhibits IIa, cofactor for heparin and dermatan sulfate ("minor antithrombin")

protein C

inactivates Va and VIIIa

protein S

cofactor for activated protein C (APC, inactive when bound to C4b-binding protein)

protein Z

mediates thrombin adhesion to phospholipids and stimulates degradation of factor X by ZPI

Protein Z-related protease inhibitor (ZPI)

degrades factors X (in presence of protein Z) and XI (independently)

plasminogen

converts to plasmin, lyses fibrin and other proteins

alpha 2-antiplasmin

inhibits plasmin

tissue plasminogen activator (tPA)

activates plasminogen

urokinase

activates plasminogen

plasminogen activator inhibitor-1 (PAI1)

inactivates tPA & urokinase (endothelial PAI)

plasminogen activator inhibitor-2 (PAI2)

inactivates tPA & urokinase (placental PAI)

cancer procoagulant

pathological factor X activator linked to thrombosis in cancer