Chromatography of vWf on dextran sulphate sepharose

A relatively simple and reproducible chromatographic separation using Dextran Sulphate (DS) Agarose is described for the purification of vWf:Ag from cryoprecipitate or plasma source material. The elution profiles suggest high affinity of vWf for the matrix permitting resolution from Fibrinogen, IgG and the unbound Albumin. The major contaminant fibronectin can be removed prior to the chromatography step by Gelatin-Sepharose adsorption. Chromatography of 125I-vWf, added to cryoprecipitate as a marker, gives two distinct peaks one of which elutes with the column wash through fractions and expresses negligible biological activity. The re-eluted bound material expresses normal vWf:RCo activity with full multimer integrity as assessed by SDS Agarose electrophoresis. DS sepharose chromatography offers an excellent method for the purification of 125I-vWf since all the viable label is resolved from excess free radiolabel and denatured protein. Low recoveries of VIII:C were demonstrated at both R.T. or 4 degrees C possibly due to the presence of Tri-Sodium citrate and the absence of sufficient free CaCl 2 in the buffers.