In naturally infected T cells a substantial fraction of Tax co-localizes with the MTOC. Images of CD4+ T cells naturally infected with HTLV-1 obtained from a TSP/HAM patient. Cells were stained with anti-Tax mAb Lt-4 (green) and monoclonal anti-β Tubulin-Cy3 antibody (red). The view represents a projection (XY axis) of adjacent confocal sections. Scale bar = 10 μM.