Plasma fraction containing bikunin, method for the production thereof and use of the same

#The present invention relates to a process for the preparation of a plasma fraction containing bikunin, the obtainable product, and its use in septic conditions.

#Bikunin is a proteinase inhibitor having a number of physiological functions. In plasma, it is mostly present as a subunit of pre- and inter-α-trypsin inhibitor (IαI). However, in the bound form, a lower bikunin activity is found as compared to the free form. The wide variety of activities of bikunin also include the inhibition of plasmin on the cell surface, and the stimulation of neutrophils by lipopolysaccharides, which suggests a role in inflammatory reaction. In “The International Journal of Biochemistry Cell Biology”, 32, 125-137 (2000), the structure and function of bikunin is discussed.

#Bikunin is often referred to as the light chain of IαI or its subunit 1. Another term is the “IαI family of plasma proteins”, which consists of different structurally related molecules. A survey thereof is presented by J. P. Salier et al. (Biochem. J. 315, 1-9 (1996)). To form IαI, bikunin is integrated with various heavy (H) chains by covalent binding. Through chondroitin-4-sulfate, a protein-glycosaminoglycane-protein linkage is formed.

#The invention is further described by the following Examples.

#1. Preparation of the Bikunin Plasma Fraction

#Plasma cryoprecipitate was treated with TNBP and Triton for the inactivation of viruses. Then, the mixture was separated through the anion exchanger EMDTMAE-Sephadex, a tentacle gel, to obtain a fraction containing factor VIII and vWF. This fraction was further separated using molecular size exclusion chromatography on Superose 6 (Pharmacia). The high molecular weight fraction containing vWF and the FVIII/vWF complex was separated off, and the fraction containing molecules having an apparent molecular weight within a range of from 100 to 500 kDa was recovered.