FIGURE 7.

Gangliosides reconstitute entry of HCR/T into PC12 cells treated with the glycosphingolipids synthesis inhibitor PPMP. a, PC12 cells were incubated with 25 μm PPMP for 48 h and then loaded with the indicated ganglioside(s) in the presence of PPMP for an additional 24 h. The cells were washed and incubated with 100 nm HCR/T and 10 μg/ml Alexa Fluor 488-Transferrin (Tfn) at 37 °C. Cell-associated HCR was visualized as described above. b, fluorescence was quantified in 20 random fields, averaged, and presented as a fluorescence intensity ratio of bound HCR/Transferrin with standard deviation. Background fluorescence intensities in the absence of exogenous ganglioside loading were subtracted from the ganglioside treated groups. Two-tailed Student's t test, p values <0.05 at the 95% confidence level are indicated by (**) for lined analyses.