[Diagnosis and classification of hematologic tumors using anti-lymphocyte monoclonal antibodies]

Many hybridoma monoclonal antibodies to lymphocytes of T cell and B cell lineage and of both T and B cell lineage and stem cells were newly developed and characterized. Lymphocyte surface antigens that appear at the specific stages of T and B cell differentiation were clearly detected by these monoclonal antibodies. These antigens were also expressed on the cell surface of lymphatic leukemias and malignant lymphomas, suggesting the differentiation stages from which the tumor was derived. Leukemias and malignant lymphomas were diagnosed and classified objectively with these monoclonal antibodies. Immunohistochemical approach with the antibodies was very helpful for diagnosis of malignant lymphomas. Since the cell surface phenotypes are often related to biological behavior of the cell, the classification was expected to reflect the pathologic expression of tumor cells, and to have relationship with the clinical course of the patients with lymphoid malignancies. In fact, it has been suggested that the classification of leukemia and lymphoma based on the antigens defined by the monoclonal antibodies is related to the clinical features and prognosis of the patients.