Figure 1.

Induction of NF-κB activity in the lungs of p50^+/+ but not p50^−/− mice. Mice were either sensitized with OVA+ alum followed by an aerosol challenge with OVA (OVA/ OVA) or sham-sensitized with alum only and OVA-challenged (Alum/OVA). Nuclear extracts prepared from the lungs of animals subjected to Alum/OVA or OVA/OVA were used for EMSAs. A ³²P-labeled oligonucleotide containing a consensus NF-κB– binding sequence was used to detect the κB-binding activities. Binding reactions were carried out in the presence or absence of specific antibodies (Ab) as indicated. In parallel reactions, binding reactions were also carried out with recombinant p50 (rp50; Promega Corp., Madison, WI). The probe was incubated with rp50 in the presence or absence of anti-p50 Ab (lane 9) or anti-p65 Ab (lane 10; used as a control). The p50 homodimer and the p50–p65 heterodimer are indicated as complexes I and II, respectively. Nonspecific binding to the probe is shown by an arrow and the intensity of this complex was variable in different experiments. Binding reactions were analyzed by electrophoresis on 6% native polyacrylamide gels as described previously (33, 90).