Innate and acquired immunity intersect in a global view of the acute-phase response.

Recognition of stereotypic chemical patterns by sentinel cells of the innate immune system provokes a transient deviation from homeostasis, the acute-phase response (APR). Although APR effectors have been identified individually, the complexity of the response suggested that emergent properties would be uncovered by a more comprehensive examination. Our global assessment revealed that approximately 7% of genes in the mouse are mobilized in the hepatic APR to endotoxin. Extensive metabolic adjustments include suppression of pathways for cholesterol, fatty acid, and phospholipid synthesis. Increased expression of genes for innate defense was accompanied by coordinate induction of the MHC class I antigen presentation machinery, illustrating an intersection between innate and adaptive immunity.