Reactivity of antibody in acute myeloid leukaemia with proliferation-associated nuclear antigen(s).

A reaction between antibody in leukaemic sera and nuclear antigen present in leukaemic cells was detected by means of an anticomplement immunofluorescence test. The antibody was found mainly in patients with myeloid leukaemia, particularly those with a high percentage of blast cells in their peripheral blood. The nuclear antigen(s), however, was present in various proportions of the circulating cells of almost all patients with leukaemia, lymphoma or infectious mononucleosis, as well as in phytohaemagglutinin-transformed blasts and proliferating cell lines. Thus, antibody appeared to be detecting a nuclear component associated with cell proliferation.