Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 31, 1997
Publication Date: N/A
Interpretive Summary: Infection of cattle with Mycobacterium paratuberculosis causes a chronic intestinal disease called Johne's disease. Johne's disease causes diarrhea, weight loss, decreased milk production, and death in dairy cattle. Control of the disease is complicated because of the long incubation period (years) and a lack of understanding of how the bacterium persists in the cells of the cow. In this study, techniques were develope to isolate phagocytic cells from the blood of cows and to assess their capability to defend against bacterial infections. These techniques will be useful to enhance our understanding of the immune response of the cow to M. paratuberculosis and how the bacteria survives inside of cells. These assays will also be useful to other researchers for the study of the immune response of cattle to other bacterial infections.
Technical Abstract: Bovine monocytes were isolated from the peripheral blood of cattle by adherence of peripheral blood mononuclear cells to plastic. Three in vitro methods were modified to evaluate bovine monocyte function. These methods were: 1) ingestion of 125I-iododeoxyuridine labeled Staphylococcus aureus, 2) antibody-dependent cell-mediated cytotoxicity, and 3) luminol-dependent and native chemiluminescence. Description of monocyte isolation and assay development is discussed in the text. Assays to evaluate monocyte function are useful for assessing immune status of the animal.