Submitted to: American Association of Veterinary Laboratory Diagnosticians
Publication Type: Abstract Only
Publication Acceptance Date: 11/3/2001
Publication Date: N/A
Technical Abstract: White-tailed deer (Odocoileus virginianus) are wildlife reservoirs for Mycobacterium bovis infection of domestic cattle in northeast Michigan. Production of nitric oxide (NO) by activated macrophages is a potent mechanism of mycobacterial killing. The capacity of macrophages to produce NO, however, varies between mammalian species. The objective of this study was to determine if mononuclear cells isolated from white-tailed deer produce nitrite as an indication of NO production and, if so, is NO produced in response to stimulation with M. bovis antigens. Supernatants were harvested from adherent peripheral blood mononuclear cell (PBMC) cultures that had been stimulated with either haemolytica lipopolysaccharide (LPS) or media alone (e.g., no stimulation). Nitrite levels within . haemolytica LPS-stimulated culture supernatants exceeded (p < 0.05) that detected within supernatants from non-stimulated cultures as well as that detected within supernatants from cultures receiving in addition to haemolytica LPS. In response to stimulation with M. bovis antigens, nitrite production by PBMC from M. bovis-infected deer exceeded (p < 0.05) the production by PBMC from non-infected deer. The response of PBMC from infected deer to M. bovis antigens exceeded (p < 0.05) the response of parallel cultures receiving no stimulation. The response of PBMC from M. bovis-infected deer to M. avium antigens did not differ from the response of M. bovis-infected deer to no stimulation or from the response of non-infected deer to M. avium antigens. These findings indicate that adherent PBMC from white-tailed deer are capable of NO production and that mononuclear cells isolated from M. bovis-infected white-tailed deer produce NO in an antigen-specific recall response.