Purification of syndecan-1 from U-266 cell line.

Soluble syndecan-1 was purified from conditioned medium of U-266 myeloma cells. Four microliters of sample from each purification step was loaded onto a precasted gel (4% to15%). Proteoglycans were detected by combined alcian blue/silver staining.27 By this procedure, GAG chains stain before proteins. The development step was stopped after approximately 2 minutes in this experiment, therefore mainly GAG chains and albumin appear. Lane A: conditioned medium from U-266 cells. Lane B: after Q-sepharose column to remove serum proteins and reduce the volume of the sample. Lane C: after purification of the sample on a B-B4 immunoaffinity column (albumin added to sample after purification).