Influence of cell sources, stimulating agents, and incubation conditions on release of interleukin-1 from chicken macrophages

Experiments were conducted to determine the cell source, stimulating agents, and incubation conditions that maximize interleukin-1 (IL-1) release by chicken macrophages/monocytes. Thymocyte co-mitogen proliferation was used to assay IL-1 activity of conditioned or partially purified supernatants. Monolayers of a transformed chicken macrophage cell line, HD11, released greater amounts of IL-1 than adherent cells isolated from peripheral blood, peritoneal cavity, or spleen. E. coli endotoxin and heat-killed S. aureus induced greater release of IL-1 by HD11 and splenic macrophages than latex or a super induction protocol with mezerien. Blocking macrophage eicosanoid synthesis with indomethacin did not influence IL-1 release from HD11 macrophages. Removing low molecular weight compounds from conditioned supernatants by dialysis did not influence IL-1 activity. IL-1 release was increased by incubating macrophages at 42 C compared to 39 C. Thymocyte co-mitogenic activity of IL-1 was increased by incubating thymocytes at 42 C compared to 39 C. Species cross reactivity between chicken and mammalian IL-1 was also investigated. Chicken IL-1 had slight co-stimulation activity on murine thymocytes, but murine and human IL-1 were without activity on chicken thymocytes.