Chicken tumor necrosis-like factor. I. In vitro production by macrophages stimulated with Eimeria tenella or bacterial lipopolysaccharide.

HD11, a transformed avian macrophage cell line, and chicken peripheral blood leukocyte-derived macrophages (PBL-M phi) were stimulated with bacterial endotoxin lipopolysaccharide (LPS) or Eimeria tenella sporozoites and merozoites. The specific cytotoxicities of the culture supernatants against different target cell lines were measured, and the kinetics of tumor necrosis-like factor (TNF) production by HD11 and PBL-M phi were also measured. The results showed that HD11 and PBL-M phi secreted a TNF-like factor when stimulated with Eimeria parasites or LPS. A time- and dose-dependent TNF-like factors production by PBL-M phi was observed poststimulation with Eimeria parasites. Chicken TNF-like factor preferentially kills CHCC OU-2 cells, a fibroblast cell line of chicken origin, when compared to LM cells, a murine cell line used for mammalian TNF. This study indicates that chicken M phi produce a significant level of TNF-like factor following coccidial infection.