FIGURE 3.

Functional LRP1 co-localizes with PDGFR-β after activation by PDGF. WI-38 fibroblasts were incubated with monoclonal antibody 5A6 to label the endocytic pool of LRP1. The cells were then chilled and incubated with PDGF (30 nm) for 1 h at 4 °C before raising the temperature to 37 °C for 12 min. Fixed and permeabilized cells were then stained for PDGFR-β. The position of the nucleus is outlined by dashed lines. The scale bar is 5 μm.