Files in this Data Supplement:

• Movie 1, Fig. 4A (AVI Video, 490 KB) - Early clustering of 2B4-GFP. 2B4-GFP transfected NK cells were studied by time lapse confocal videomicroscopy. 2B4-GFP protein is clusterized 30 sec. after the contact between the NK cell and the 721.221 target cell occured.
  
  
• Movie 2, Fig. 4B (AVI Video, 1,136 KB) - Dynamics of 2B4-GFP on resting NK cells during the contact with three 721.221 target cells. Clusters of 2B4 were formed as soon as each contact occurred and the last one was maintained during the whole interaction period (20:30 min.).
  
  
• Movie 3, Fig. 4C (AVI Video, 778 KB) - Dynamics of SAP-GFP on resting NK cells. The signaling adaptor SAP formed maintained clusters at NK cell-target cell contact.
  
  
• Movie 4, Fig. 5A (AVI Video, 560 KB)
• Movie 5, Fig. 5B,(AVI Video, 1,272 KB) - Figures 5A and B, respectively: Connective structure formed in resting NK cells after detachment from the target cell. A high concentration of 2B4 and SAP were observed in this structure. In Movie 4, a patch of 2B4 remained on the target cell after connective structure disruption.