Detection of a tumor-associated antigen on the surface of human myelogenous leukemia cells.

Membrane extracts of human acute myelogenous leukemia cells were passed over immunoadsorbent columns containing antibodies directed to equivalent preparations of pooled normal peripheral blood leukocytes. This material, when compared to equivalent normal cell preparations on nonreducing polyacrylamide gels, demonstrated the presence of four unique bands, not found in normal cell preparations. With the use of a previously described leukemia-specific heteroantiserum, these bands, after elution, were tested for reactivity with the antiserum. The eluted material containing reactive antigen was used to immunize rabbits. The resulting antiserum showed strong reactivity with myelogenous leukemic cells extracts and none with normal materials. A series of bone marrow samples from patients with a variety of lymphoproliferative and myeloproliferative disorders were tested with this antiserum in the fluorescence-activated cell sorter. In every instance, bone marrow cells from patients with acute myelogenous leukemia and chronic myelogenous leukemia showed strong positive fluorescence with this antiserum. However, no bone marrow cells from patients with lymphoproliferative disorders or patients with other leukemias showed any fluorescence above background with this antiserum.