Figure 4. Inhibition of HA-CSO NP uptake. NP uptake was measured by fluorometry. A: Both azide and 4 °C significantly decreased NP uptake in HCE (black bars) and IOBA-NHC (white bars) cells. B: Blocking the HA-receptors with Hermes-1 or with an excess of HA resulted in a significant reduction of NP uptake. C: Filipin, a specific caveolin-dependent endocytosis inhibitor, significantly reduced HA-CSO NPs uptake in both cell lines while CPZ, a specific clathrin-dependent endocytosis inhibitor, did not (*p-value<0.05; n=4).