Figure 8
From: Addition of lysophospholipids with large head groups to cells inhibits Shiga toxin binding
LPL treatment changes plasma membrane lipid packing.
(a) HEp-2 cells were treated with 10 μM LPI, LPE, LPC 18:0, LPC 18:1 or 0.2% ethanol (EtOH) for 20 min, or with 5 mM mβCD for 45 min, prior to staining with 10 nM NR12S. Spectral imaging was started 7 min after the addition of NR12S and continued for up to 15 min. The analysis of the spectra was performed on at least 20 manually selected regions of the plasma membrane for each condition. The panel to the left shows the data from one of three independent experiments with LPI, LPE and mβCD and the panel to the right shows data from one of two independent experiments with LPC 18:0 and LPC 18:1 (mean ± STD). (b) The average GP value for each selection was quantified as described in materials and methods and the figure shows differences in GP values between the EtOH and the treated samples (mean ± SEM; n ≥ 2). (c) Pseudo-coloured TIRF images of the basal plasma membrane following cell treatment with 0.2% EtOH or 10 μM LPI. The dark blue structures are the coating of the Lab-Tek dish stained by NR12S. The colour scale for GP values is shown on the right; scale bar 10 μm. (d) Differential interference contrast images showing morphology of HEp-2 cells, taken 10 min prior to and 10 min after addition of 0.2% EtOH, 10 μM LPI or 10 μM LPE; scale bar 10 μm.
