Figure 14

a-l Organization of vimentin in A549 cells after treatment with etoposide - fluorescence microscopic examination (vimentin indirect labeling, secondary antibody was goat anti-mouse IgG-BODIPY). a-c Control cells, d-f 0.75 μM etoposide, g-i 1.5 μM etoposide, j-l 3 μM etoposide; a, d, g, j vimentin labeling, b, e, h, k DAPI, c, f, i, l merged. Staining with this method allow us to visualize in a great detail subtle threads of vimentin filaments located in the invaginations of nuclei. Apart from regularly organized bundles of filaments in the control cells, abundant, but more heterogeneously organized structures appeared as a result of the treatment. Thick arrows point at thin threads in the nuclear invaginations or more dense vimentin bundles in the form of septum-like aggregates between sister nuclei, especially common in multinucleated cells; double thick arrows - cells presenting long vimentin tails (vimentin staining), closely located sister nuclei or thin chromatin threads connecting closely located sister nuclei (DAPI); arrowheads - diffuse vimentin staining around nuclei with features of karyorrhexis or karyolysis. Results are indicative of five independent experiments. Bar 50 μm.