Thierry Burnouf, PhD, Director, Plasma Fractionation Unit, Centre Régional de Transfusion de Sanguine de Lille.
A therapeutic, highly purified factor XI concentrate from human plasma
Article first published online: 28 FEB 2003
Volume 32, Issue 9, pages 861–867, November-December 1992
How to Cite
BURNOUF-RADOSEVICH, M. and BURNOUF, T. (1992), A therapeutic, highly purified factor XI concentrate from human plasma. Transfusion, 32: 861–867. doi: 10.1046/j.1537-2995.1992.32993110761.x
- Issue published online: 28 FEB 2003
- Article first published online: 28 FEB 2003
- Received for publication January 17, 1992; revision received May 8, 1992, and accepted May 13, 1992.
A highly purified factor XI (FXI) concentrate was prepared from human plasma by a process comprising a filter adsorption step and chromatography on a cation exchange resin. The freeze-dried FXI, which solubilized quickly, had high specific activity (130–150 U/mg protein), high potency (approx. 100 U/mL), and excellent stability for at least 24 hours at room temperature in the liquid state. The overall recovery was about 220 U of FXI per liter of plasma. Minor protein contaminants (C1-inhibitor, fibronectin, IgG, and alpha-2-macroglobulin) were found to be between 0.13 and 0.46 mg per 1000 U of FXI. Fibrinogen and relevant coagulation factors (factors II, V, VII, IX, X, XII, XIII, and VIII/von Willebrand factor) were undetectable, as evidenced by immunologic and immunoelectrophoretic data. Components of the kinin system were present in trace amounts or were undetectable. No evidence of activated factors such as factors Xa and IXa was found. Proteolytic activity, as assessed by S-2288 chromogenic substrate, was negligible and thrombin was undetectable. A solvent-detergent treatment was included prior to chromatographic purification to enhance viral safety against lipid-enveloped viruses. In vitro and in vivo animal studies demonstrated the absence of thrombogenic, hypotensive, or toxic effects. No thrombogenic activity was found in the Wessler model in rabbits at doses of 900 to 1100 U of FXI per kg of body weight. This FXI preparation could be beneficial in substitution therapy of congenital or acquired FXI deficiency, especially as a way to avoid the use of fresh-frozen plasma.