ML120B inhibits NF-κB activation in vivo. (A) Pharmacokinetic analysis of IKKβ inhibitor ML120B. Mice were given a single oral dose (300 mg/kg) and plasma concentration was determined at 1, 4, 8, and 24 hours after dosing (n = 3 mice per time point). (B) Western blot analysis of IκBα, phosphorylated IκBα (p-IκBα), and FOXO3a in purified bone marrow B cells 1, 2, 3, and 4 hours after a single oral dose of ML120B. Marrow was isolated at indicated times and B cells were purified by negative selection by removing non–B cells with antibodies to Mac1, CD3, Gr-1, and Ter199-PE and passing cells through a magnetic bead separation column. (C) Image of luciferase activity in transgenic mice. Mice were given a single oral dose of vehicle or ML120B (300 mg/kg) and 1 hour later injected with LPS and photographed 4 hours later after injection of D-luciferin. (D) Naive mice, mice treated with vehicle and LPS, or mice treated with ML120B and LPS were evaluated. Individual organs were removed and photon counts were collected (n = 3 per group).