DNA-binding activity of the transcription factor NF-κB by B-CLL cells with or without 11q deletion detected using a³²P-labeled oligonucleotide probe containing a high-affinity NF-κB binding site. Shown are also the scores of NF-κB activity. The Jurkat cells stimulated with TNF- served as positive control (+) and unstimulated Jurkat cells were used as negative control (−) for NF-κB-activity. The solid arrowhead indicates the position of NF-κB DNA complexes. (○) Nonspecific activity binding to the probe. The open arrowhead shows unbound oligonucleotide.