Effect of Endotoxin on Macrophages of the Adult Chicken

Different concentrations of endotoxin were added to cultures of adult chicken's spleen growing in a coagulated plasma medium. Endotoxin in concentrations of 0.1 and 1.0 μg/ml did not alter the early migration of leucocytes and macrophages, but stimulated the extent of macrophage migration after the second day of incubation. Concentrations of endotoxin between 5 and 50 μg/ml caused an initial decrease in macrophage migration followed by a definite increase in a majority of experiments. Morphologic changes due to endotoxin were not observed. The low toxicity of endotoxin for avian macrophages was different from the severe toxic action on mammalian macrophages previously observed under similar cultural conditions.