bFGF induces an enhanced binding of EC to HA. (A) Control and bFGF (10 ng/mL) pretreated HUVEC were incubated with FITC-conjugated HA. Specificity of binding was determined by pretreatment of cells with 1 μg/mL 515 anti-CD44 antibody and by addition of excess (2.5 mg/mL) soluble HA. Results are expressed as the mean percentage of HA-binding cells of three experiments (± SEM). CD44⁻ EC represent HUVEC directly used after isolation. The bar identified with “control” represents HUVEC that were not incubated with HA-FITC. (B) through (F) show the FACS-plots of one experiment in which green fluorescence (HA-FITC) is plotted against SSC. The percentage HA-FITC binding cells is indicated in the upper right corner.