In incubation studies performed from 0.25 – 9 h, LPS increased NF-κB up to 1 h (p < 0.0001) and these increases were inhibited with parthenolide (p = 0.002) (Panel C). For these studies, nuclear protein was extracted from cell pellets, the protein concentration determined and NF-κB DNA binding activity assays were performed using a Trans-AM ELISA-based kit from Active Motif (Carlsbad, CA). This assay employed an oligonucleotide containing the NF-κB p65 consensus binding site and an antibody specific for p65, to isolate and detect this subunit respectively [13].