Patent ID: 8529909

Claim:
A process for producing purified BLV gp51 antigen that is useful in an ELISA assay for diagnosing enzootic bovine leukemia comprising i) culturing FLK-BLV cells in cell culture medium that is totally devoid of bovine serum, wherein the culture of FLK-BLV cells is maintained for 2 to 3 days, and wherein the FLK-BLV cells produce BLV gp51 antigen; ii) collecting the medium from the above FLK-BLV cells containing the BLV gp51 antigen produced by the FLK-BLV cells; iii) concentrating the BLV gp51 antigen in the medium at least 10-fold by ultra-filtration; iv) dialyzing the condensed BLV gp51 antigen against 20 mM Tris-HCl pH 7.5; and v) purifying the BLV gp51 antigen in a column comprising an anion exchange medium, wherein the BLV gp51 antigen is eluted from the column with a sodium chloride gradient.