Cytotoxic Antibody Reactive With Cultures of Lymphoid Cells: Occurrence in Disease and Normal Human Sera

Summary

The effect of disease and other factors on the expression of a natural cytotoxic antibody in human serum was studied. The incidence and titer of the antibody were higher in the sera of patients with Burkitt's lymphoma. In contrast, reactivity in the sera of patients with leukemia was lower than that in normal controls. The antibody level in chronic leukemia was inversely related to the peripheral leukocyte count. During the acute phase of infectious mononucleosis, antibody levels were low. The possibility of in vivo absorption of the cytotoxic antibody by the abnormal cells is discussed. Present evidence indicates that the cytotoxic antibody is an IgG immunoglobulin.