A549 cells(black) were incubated in 5% BSA blocking buffer for 30 min at room temperature. Cells were then stained with Heparan Sulfate Antibody（bs-5072R） at 1:50 dilution in blocking buffer and incubated for 30 min at room temperature, washed twice with 2% BSA in PBS. Acquisitions of 20,000 events were performed. Cells stained with primary antibody (green) and isotype control (orange).