Fig. 1: rVAR2:dextran binds CS on cancer cells with high specificity.
From: Multi-cancer detection of circulating tumor cells by targeting oncofetal chondroitin sulfate
a Graphic representation of the rVAR2:dextran staining strategy. b Binding of PE-labelled rVAR2:dextran to three cancer cell lines (ES-2, COLO205, A549) and PBMCs from a healthy donor as measured by flow cytometry (mean and SD of triplicate measurements). c Staining of the cancer cell lines with 4 nM of biotinylated rVAR2 or rVAR2 mutant (DBL1-ID2a 555AAAAIAAA562) coupled to the PE-labelled dextran backbone (orange). The cell nuclei were counterstained with DAPI (blue). d, e Binding of PE-labelled rVAR2:dextran to the cancer cell lines with or without pre-treatment with Heparinase (2.5 mU/mL Heparinase II + 5 mU/mL Heparinase III) or Chondroitinase ABC (20 µg/mL) as measured by flow cytometry (mean and SD of triplicate measurements). P-value were determined by one-way ANOVA, ns = non-significant, ***p < 0.001. f Binding of PE-labelled rVAR2:dextran to the cancer cell lines with or without competition with 25 µg/mL soluble heparan sulfate (HS) or soluble chondroitin sulfate (CS). Graph shows mean and SD of triplicate measurements.
