Cervine T-lymphocyte growth factors and their measurement in tuberculosis

Research into the composition and function of the immune response in domesticated ruminants has tended to focus on the ovine and bovine systems. With the recent domestication of deer, health problems have developed which require a fundamental knowledge of the immune function in exotic ruminants. In this report it is shown that although recombinant human and mouse interleukin-2 (IL-2) were capable of stimulating cervine T-cell proliferation, optimal proliferation was only achieved using recombinant bovine IL-2. While some phylogenetic restriction of IL-2 cross-reactivity was found, in some cases this could be overcome by using high concentrations of recombinant IL-2. Using cervine T-cell blasts it was possible to assay in vitro T-cell growth factor (TCGF) production by lymphocytes isolated from deer naturally exposed to tuberculosis Mycobacterium bovis). Differences were found in the amount of TCGF present in the supernatants of antigen-activated cells isolated from severely diseased animals, those with limited disease and non-diseased animals.