To characterize the inflammatory reactions in pulmonary and extrapulmonary tissues, sections from lungs [23] , tracheobronchial and retropharyngeal lymph nodes, tonsils, spleen, heart, liver, right kidney, colon and ileum as well as several areas of the brain were immunolabeled for Mac387 (myelomonocytic lineage marker), CD83 (mature dendritic cells), HIF-1α, hemeoxygenase-1 (HO-1), cyclooxygenase-2 (COX-2), inducible nitric oxide syntase (NOS2), vascular endothelial growth factor-A (VEGF-A), phospho-p38α mitogen-activated protein kinase (phospho-p38α MAPK), and the apoptosis marker activated caspase-3. Brain sections were also labeled for glial fibrillar acidic protein (GFAP) to test for gliosis or loss of astrocytes, for microglial cells using the Iba-1 marker and for oligodendrocytes, using the transcription factor OLIG2 as a cell marker [30] . Sources of antibodies and immunolabeling protocols have been described in detail elsewhere [30, 31] . Positive control tissues included samples from inflammatory processes in lungs, intestine and brain of macaques, cattle, mice, guinea pigs, and cats [30] [31] [32] . The sections were counterstained with Meyer's hematoxylin (Scytek Laboratories; Logan, Utah), mounted with coverslips, and examined on an Olympus BX41 light microscope. The immunolabeling was scored semi-quantitatively on a scale of 0-6, based on the number of positive cells and the overall intensity of labeling, with 0 indicating no apparent labeling, 1 through 6 indicating increasing expression above normal levels, and a score of 6 denoting diffuse occurrence of positive cells with high-intensity labeling. For HIF-1α, the scores relate to nuclear expression (nuclear translocation) rather than cytoplasmic expression. In the instances of a marker for normal cellular constituents, such as microglia in the brain or dendritic cells in the lymphoid tissues including bronchiole-associated lymphoid tissue (BALT), normal levels were given a score of 0. The scale therefore differs for each marker but is consistent for a particular phenotype, depending on the normal tissue levels of expression in naïve animals. Photomicrographs were acquired with an Olympus Q-Color 3 camera and associated computer software and are reproduced without manipulation.