Figure 1

The CSP uptake is an energy dependent process. A. CSPs were incubated with HeLa cells at different temperatures (4°C, 25°C, 37°C) for 12 hours and were then fixed with 4% paraformaldehyde. The cells were then stained with Hoechst and were imaged using confocal microscope. B. Quantification for percentage of CSP uptake. C. ATP dependence of CSP entry was monitored by incubating CSP with HeLa cells pretreated with 2-deoxy-D-glucose and sodium azide. The panels are representative images of the cells in the presence or absence of ATP. D. Quantification for percentage of CSP uptake. E. Quantification of the total pool of intracellular ATP by using an ATP quantification kit (Invitrogen).