TAFI - Thrombin Activatible Fibrinolysis Inhibitor Deficient Plasma

TAFI – Thrombin Activatible Fibrinolysis Inhibitor Deficient Plasma

Affinity’s TAFI – Thrombin Activatible Fibrinolysis Inhibitor Deficient Plasma is manufactured from pooled normal human plasma depleted of TAFI using antibodies directed to TAFI. Only the highest quality citrated plasma is used as starting material. Our Frozen Deficient or Depleted Plasma products are typically buffered with the addition of HEPES to 20mM final concentration and our Lyophilized Deficient Plasma products are typically buffered with the addition of HEPES to 50mM final concentration.

All TAFI – Thrombin Activatible Fibrinolysis Inhibitor Deficient Plasma or Depleted Plasma from Affinity Biologicals are for Research Use Only and must not be used for diagnostic applications.

TAFI Deficient – Depleted Plasma

TAFI Deficient – Depleted Plasma is manufactured from normal citrated human plasma that has been depleted of TAFI Deficient – Depleted Plasma by selective affinity immuno-adsorption using antibodies directed towards TAFI. Available in two different formats – Frozen and Lyophilized

Only the highest quality citrated plasma is used as starting material and in many cases the parent plasma is available as control material. Our TAFI Deficient – Depleted Plasma can be used for further manufacturing or research use only applications.

Frozen TAFI Deficient Plasma

Product Code: TAFI-DP

Presentation: Frozen TAFI Deficient – Depleted Plasma

Preparation/Handling: Thaw 1 ml vials in 37^oC water bath for 5 minutes; for bulk volumes, thawing time will be dependent on bottle size.

Storage and Stability: Plasma is shipped frozen and should be stored below -60^oC. Product is stable until date stated on vial label when stored at -60^oC. Once thawed, plasma is stable for 4 hours at 2-8^oC in original vial.

Certificate of Analysis: available upon request

Lyophilized TAFI Deficient Plasma

Product Code: TAFI-LDP

Presentation: Freeze Dried TAFI Deficient – Depleted Plasma containing 50 mM HEPES and stabilizers.

Reconstitution: Reconstitute with 1 mL of reagent grade water. Allow contents to dissolve for 15 minutes at room temperature with occasional swirling. Stability after reconstitution is 4 hours at ambient (18-25^oC), or 30 days at –20^oC.

Storage and Stability: Prior to reconstitution, dried plasma should be stored at 2-8°C. Product is stable until date stated on vial label when stored at 2-8^oC. Stability after reconstitution is 4 hours at ambient (18-25^oC), or 30 days at –20^oC.

Certificate of Analysis: available upon request

Description of Thrombin Activatible Fibrinolysis Inhibitor (TAFI)

TAFI (Thrombin Activatable Fibrinolysis Inhibitor), also referred to as plasma procarboxypeptidase-B, procarboxypeptidase-U and R, circulates in plasma as a zymogen with a mass of 58,000 daltons (1-6). Proteolytic activation of TAFI yields an N-terminally derived activation peptide and the C-terminal portion corresponding to the metalloprotease, activated TAFI (TAFIa). TAFIa exhibits exopeptidase activity with carboxypeptidase B-like substrate specificity capable of catalyzing the hydrolysis of C-terminal lysine and arginine residues. Cleavage of these residues on fibrin by TAFIa attenuates clot lysis by inhibiting the formation of the ternary activation complex comprising fibrin cofactor, tPA and plasminogen, thereby inhibiting plasmin generation. Although TAFI can be activated by various proteases including thrombin and plasmin, the physiological activator is proposed to be the complex thrombin-thrombomodulin since the rate of activation is stimulated 1250-fold compared to thrombin alone (4). However, the rate of TAFI activation is highly dependent upon its plasma concentration. Since TAFIa apparently plays a key role in connecting coagulation and fibrinolysis and significantly increases clot stability, determination of plasma concentration of TAFI is likely crucial to assess its subsequent potential antifibrinolytic effects^1-6.

References and Review

Eaton, D.L., Malloy, B.E., Tsai, S.P., Henzel, W., Drayna, D., Isolation, Molecular Cloning and Partial Characterization of a Novel Carboxypeptidase B from Human Plasma. J.Biol.Chem. 266:21833-21838, 1991.
Hendriks, D., Scharpe, S., van Sande, M., Lommaert, M.P., Characterization of a carboxypeptidase in human serum distinct from carboxypeptidase N. J.Clin.Chem.Clin.BioChem. 27:277-285, 1989.
Campbell, W., Okada, J. An Arginine specific carboxypeptidase generated in blood during coagulation of inflammation which is unrelated to carboxypeptidase N or its subunits. Biochem.Biophys.Res.Commun. 162:933-939, 1989.
Bajzar, L., Morser, J., Nesheim, M.E. TAFI, or procarboxypeptidase B, couples the coagulation and fibrinolytic cascades through the thrombin-thrombomodulin complex. J.Biol.Chem. 271:16603-16608, 1996.
Mosnier, L.O., von Dem Borne, P.A. Meijers, J.C., Plasma TAFI levels influence the clot lysis time in healthy individuals in the presence of an intact intrinsic pathway of coagulation. Thromb.Haemost. 80:829-835, 1998.
Juhan-Vague, I., Renucci, J.F., and Grimaux, M., Morange, P.E., Gouvernet, J., Gourmelin, Y., Laessi, M.C. Thrombin Activatable Fibrinolysis Inhibitor Antigen Levels and cardiovascular Risk Factors. Arter.Thromb.Vascular.Biology. 20:2156-2161, 2000.