GB1380270A - Process for isolating a fibrin-stabilizing factor - Google Patents

Abstract

1380270 Isolating fibrin-stabilizing factor BEHRINGWERKE AG 22 Dec 1971 [22 Dec 1970] 59721/71 Heading ASB A process for isolating a fibrin-stabilizing factor comprises carrying out, in the cold, the following steps: (a) a solution of diamino-ethoxy-acridine lactate is added, at apH of from 5.0 to 7.5, to a protein-containing extract which has been prepared from human placentae using a sodium chloride solution and which has been freed from solid contaminants, whereby a precipitate is obtained, the amount of lactate solution corresponding to 6-10% by weight of the lactate calculated on the protein and (b) the precipitate formed in step (a) is separated off, is optionally washed several times, and is dissolved in a dilute alkali metal chloride solution, having a pH of from 7.0 to 8.0 containing a complex-forming agent; (c) inactive accompanying substances are precipitated from the solution formed in step (b) after separating off insoluble substances and, optionally further dilution, by adding a quaternary ammonium base; (d) diamino-ethoxy-acridine lactate is added to the solution formed in step (c) whereby a precipitate is obtained; (e) the precipitate obtained in step (d) is decomposed, after removal of the supernatant substance, by adding a dilute alkali metal chloride solution having a pH of from 7.0 to 8.0 containing a complex-forming agent, and the residue is separated off; (f) 20-30% by weight of solid ammonium sulphate are added to the filtrate obtained in step (e), the precipitate formed is separated off after some hours and is then formed into a paste with a dilute solution of a complex-forming agent and the paste is dialysed using a tris (hydroxymethyl)-amino-methane hydrochloric acid buffer solution containing a complexforming agent and NaN 3 ; (g) the remaining dialysate is gel-filtered at a neutral pH, after separation off of contaminants at a pH of about 6, a precipitate is separated from the active fractions by means of solid ammonium sulphate and is dissolved in neutral tris-EDTA buffer; (h) the solution obtained in step (g) is dialysed using a neutral tris-EDTA buffer, the factor XIII is precipitated from the remaining solution at a pH of about 5.0 in the form of euglobulin; and optionally (i) the precipitate formed in step (h) is separated off and is dissolved in a physiological sodium chloride solution containing a complexforming agent, a stabilizer is added to the solution, and the solution is filtered under sterile conditions, dialysed, standardized and, optionally lyophilized.