Size exclusion chromatography of proteoglycans after digestion with glycosaminoglycan-specific enzymes from the supernatant (A) and cell extract (B) of the immature erythroid progenitor cell line HEL. Proteoglycans isolated by anion exchange chromatography from the supernatant (A) and cell extract (B) of HEL cells were submitted to size exclusion chromatography on a TSK 4000 column. Elution profiles are shown for the native, HNO₂-treated, heparinase/heparitinase (Hep/Hept), and chondroitinase AC/ABC-treated (AC/ABC) samples. Elution profiles were monitored by liquid scintillation counting.