The inflammatory versus constitutive trafficking of mononuclear phagocytes into the alveolar space of mice is associated with drastic changes in their gene expression profiles

Mononuclear phagocytes enter the lungs both constitutively to maintain alveolar macrophage and dendritic cell homeostasis as well as during lung inflammation, where the role of these cells is less well defined. We used a transgenic mouse strain (CX3CR1+/GFP) that harbors a green fluorescent protein (GFP) label in circulating monocytes to identify and sort these cells from the vascular and alveolar compartments under both constitutive and acute lung inflammatory conditions. Using nylon arrays combined with real-time RT-PCR for gene expression profiling, we found that flow-sorted, highly purified mononuclear phago…