Files in this Data Supplement:

• Movie S1 (QuickTime Format, 269 KB) - Actin accumulation at the T cell/APC interface
  Two interactions of actin-GFP-transduced 5C.C7 T cells with CH27 B cell lymphoma APCs under optimal conditions are shown. A bright field series of images is shown on top and the corresponding actin-GFP images as a projection of the 3-dimensional data on the bottom in a false-color scale ranging from blue (low) to green, yellow, and red (high GFP fluorescence intensity). Each frame represents a 20 second time interval during the experiment. A highly dynamic actin accumulation covering either the entire or varying subregions of the interface is shown. The 5C.C7 T cell in movie S1 is not polarized prior to APC encounter the one in movie S2 is. The movies compress 14 and 6 min of experiment into 41 and 17 sec of movie, respectively.
  
  
• Movie S2 (QuickTime Format, 304 KB) - See caption above.
  
  
• Movie S3 (QuickTime Format, 272 KB) - MTOC reorientation towards the T cell/APC interface
  An interaction of a tubulin-GFP-transduced 5C.C7 T cell with a CH27 B cell lymphoma APC is shown as in movie S1. The MTOC can be identified as the area of highest tubulin-GFP fluorescence intensity. Its rapid reorientation from the base of the uropod of the migrating T cell prior to APC contact to the T cell/APC interface is shown. The movie compresses 10 min of experiment into 30 sec of movie.
  
  
• Supplementary Material (Word Document, 38KB)