Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/5/2006
Publication Date: 9/4/2006
Citation: Paape, M.J., Sohn, E.J., Bannerman, D.D., Fetterer, R.H., Connor, E.E., Peters, R.R. 2006. Cytokine secretion by bovine polymorphonuclear neutrophil leukocytes (PMN)[abstract]. IN: 2nd European Veterinary Immunology Workshop Program and Book of Abstract. p. 13, Sept 4-6, 2006. Paris, France.
Technical Abstract: Rapid recruitment and bacterial phagocytosis and killing by PMN are the most effective defenses against establishment of infection. In addition, PMN may play a key supportive role through secretion of cytokines during the inflammatory response. We sought to determine whether bovine PMN secrete cytokines in response to stimulation with lipopolysaccharide (LPS). PMN were exposed to increasing concentrations of LPS (0, 1, 10 and 100 ug/mL) for 18 h at 37 degrees C, and cell supernatants analyzed for expression of tumor necrosis factor (TNF)-a, interleukin (IL)-1B, IL-12, IL-8 and interferon (IFN)-y by ELISA. TNF-a, IL-1B, and INF-y increased in a dose-dependent manner, while IL-12 decreased with increasing concentrations of LPS. To further study the secretion of IL-8, PMN were cultured with either RPMI, 0.1 ug LPS, 10 ng/mL human TNF-a, or 10 ng/mL bovine IL-1B. PMN were also incubated with 0.1 ug LPS plus 10 ng/mL TNF-a or 10 ng/mL IL-1B. Incubation with either LPS or LPS together with either TNF-a or IL-1B increased secretion of IL-8 when compared to RPMI. It was concluded that LPS stimulation can up-regulate the secretion of cytokines by bovine PMN, and that co-incubation of LPS with TNF-a or IL-1B had an additive effect on the secretion of IL-8. These data show that bovine PMN, in addition to their phagocytic and bactericidal properties, may play a supportive role in the innate immune response to infection by Gram-negative bacteria by producing cytokines that mediate inflammation.