Differential induction of tumor necrosis factor alpha in ovine pulmonary alveolar macrophages following infection with Corynebacterium pseudotuberculosis, Pasteurella haemolytica, or lentiviruses.
Soluble mediators such as tumor necrosis factor alpha (TNF-alpha) may be important in the pathogenesis of many chronic pulmonary infections. We examined the ability of Corynebacterium pseudotuberculosis, Pasteurella haemolytica, and ovine lentiviruses (OvLV) to induce TNF-alpha secretion by pulmonary alveolar macrophages (PAM). Bronchoalveolar lavage cells, composed of greater than 90% PAM, were obtained from normal sheep. Bronchoalveolar lavage cells were cultured for 2, 24, 48, 72, or 168 h in endotoxin-free RPMI medium (with 10% autologous serum) or in medium containing one of the following additives: lipopolysaccharide, 1-micron polystyrene beads, C. pseudotuberculosis, P. haemolytica, or one of two plaque-cloned OvLV, 85/28 or 85/34. Lipopolysaccharide, C. pseudotuberculosis, and P. haemolytica induced TNF-alpha activity in PAM cultures as early as 2 h after inoculation, as assessed by a colorimetric cytotoxicity assay. This activity could be blocked by rabbit anti-recombinant bovine TNF-alpha serum. In contrast, medium alone, polystyrene beads, and productive infection by OvLV did not induce TNF-alpha activity in PAM cultures. Bacterial pathogens which infect pulmonary macrophages may elicit the secretion of TNF-alpha within the lungs and lead to the cachectic state associated with chronic pneumonia.
Ellis
J A
JA
Department of Veterinary Sciences, University of Wyoming, Laramie 82070.
Lairmore
M D
MD
O'Toole
D T
DT
Campos
M
M
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D002478:Cells, Cultured; D003352:Corynebacterium / Q000276:immunology*; D015151:Immunoblotting; D007700:Kinetics; D016086:Lentivirus / Q000276:immunology*; D008171:Lung Diseases / Q000276:immunology / Q000382:microbiology*; D008264:Macrophages / Q000382:microbiology* / Q000648:ultrastructure; D008863:Microspheres; D010325:Pasteurella / Q000276:immunology*; D011994:Recombinant Proteins; D012756:Sheep; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha