File:Human-T-Lymphotropic-Virus-1-Visualized-at-the-Virological-Synapse-by-Electron-Tomography-pone.0002251.s006.ogv

English: Tomographic reconstruction showing the virological synapse between a naturally HTLV-1-infected CD4+ T-cell (bottom) and an autologous uninfected CD4+ T-cell cell, target cell (top). A large HTLV-1 particle (black arrow) is held between the two cell membranes and is extremely electron-dense due to the labelling against viral Gag p19 matrix protein (see also Movie S7). Parts of the two plasma membranes and inter-membrane material are also darkly stained, indicating the presence of abundant viral Gag protein. Several mitochondria have accumulated at the VS within the HTLV-1-infected CD4+ T (PBMC) which is characteristic of MTOC polarization, and is also seen in the IS. A tomogram slice showing a larger area of the 3D reconstruction can be seen in Figure 4D. The sample was fixed with PFA/glutaraldehyde, labelled against viral Gag p19 matrix protein, embedded in Agar 100 resin and post-fixed with OsO4. The reconstructed 3D volume is composed of tomograms obtained from five serial sections. The tomograms were calculated from tilt series of typically 131 images (tilt range −65° to +65°, 1° increment). The images were recorded with a 2k×2k Gatan CCD camera (pixel size 1.29 nm) at an under focus of −5.0 µm with an FEI Tecnai F30 FEG-TEM (300 kV) using the FEI software. The reconstruction was calculated using the software IMOD. The tomogram represents a volume with an area of 2.24×0.98 µm2 and a thickness of 313 nm. The scale bar at the end of the movie corresponds to 500 nm.