Mouse Model of Endotoxin-Induced Inflammation

The protocol was approved by the Institutional Animal Care and Utilization Committee of the University of California, Irvine. Eight- to 10-week-old male BALB/cJ, C3H/HeJ (Tlr4^Lps-d), and C3H/HeOuJ mice were obtained from the Jackson Laboratory (Bar Harbor, Maine). Mice were housed in isolator cages, kept on a 12-hour light–dark cycle, and provided with autoclaved bedding, water, and food. Solutions in volumes of 250 µL were injected intraperitoneally. During terminal anesthesia, blood, spleens, and lungs were obtained. Spleens were weighed, and lungs fixed in 10% buffered formalin were processed for histopathology at the Comparative Pathology Laboratory at the University of California, Davis. Plasma samples were subjected to bead-based immunoassays at Myriad RBM (Austin, Texas) for the 59 analytes of the RodentMAP version 2.0 panel. Quantitative reverse transcription polymerase chain reaction for the mouse heme oxygenase-1 gene (HMOX1) and β-actin transcripts was carried out as described on total RNA extracted from whole blood [7 (link)]. Standards were clones of the targets in a plasmid vector. HMOX1 messenger RNA (mRNA) copies were normalized per 1000 copies of β-actin mRNA.