Fig. 7. Serum starvation stimulates of cholesterol-rich MLBs. (A) Untransfected Mv1Lu cells were grown for 6 days and U18666A was added for the final 24 hours. Selected cultures were then washed and incubated for 6 hours in serum-containing (B) or serum-free (C) media and labelled with filipin. The expression of filipin-labelled MLBs was quantified from both untransfected Mv1Lu (D) and Mgat5-transfected M9 cells (E) incubated in serum-containing (empty bars) or serum-free (filled bars) media for 0.5, 1, 3 and 6 hours labelled with filipin and the nuclear dye Sytox Green. The average area of filipin-labelled vacuoles and the total area covered by these vacuoles per cell were quantified (mean±s.e.m. of three independent experiments). *P<0.005, **P<0.01, ***P<0.05 compared to areas in control cells at the same time point. Bar, 10 µm.