Abstract
Cultured rat liver cells induced a strong antibody response in syngeneic rats, directed against foetal calf serum components which were incorporated into the liver cell surface from the cell-culture medium. This antibody could be removed by absorption with liver cells or glutaraldehyde-fixed foetal calf serum. It is possible that the antigenic cross-reactivity observed in earlier studies with cultured cells treated with carcinogens could be due to this foetal calf serum component.