Fig. 7.
Size of anti-ICAM conjugates modifies their uptake by endothelial cells.
(A) DLS analysis of size distribution of the conjugates prepared at molar ratio between biotinylated anti-ICAM and streptavidin of 1:0.5 (left peak) or 1:1 (right peak). (B-C) RPMVECs were incubated for 1 hour at 37°C with anti-ICAM conjugates containing rhodamine-labeled streptavidin with mean diameters of 100-200 nm (panel B) or larger than 1 μm (panel C). The surface-bound fraction of the conjugate was double-labeled using an FITC-labeled secondary antibody. Red color (arrows) denotes internalized conjugates; yellow color (arrowheads) denotes the noninternalizable, larger conjugates. White bars in panels B and C correspond to 5 μm size. Panel C inset shows the contrast phase micrograph (× 40) minimized to the original size.