Figure 3. Assessment of binding affinity of iHA-VMA toward HA with flow cytometry. Binding of fluorescein isothiocyanate (FITC)-labeled hyaluronan acid (HA) to the ARPE-19 cell surface receptor (taken to be 100%) was monitored with flow cytometry. The addition of inhibitor of HA (iHA) in fusion with Vibrio mimicus collagenase that remains active (VMA) resulted in decreased fluorescence intensity. There was no change in signal intensity in the presence of VMA alone or irrelevant proteins (controls), such as bovine serum albumin (BSA) and CK or the cysteine knot domain of CTGF. The histogram corresponds to data from three independent flow cytometry experiments (p=0.0069, n.s., not significant).