Prostaglandin E2 reduces Toll-like receptor 4 expression in alveolar macrophages by inhibition of translation.

Alveolar macrophages (AMs) represent the first line of innate immune defense in the lung. AMs use pattern recognition receptors (PRRs) to sense pathogens. The best studied PRR is Toll-like receptor (TLR)4, which detects LPS from gram-negative bacteria.