MYELOID ANTIGEN, CD13, CD14, AND OR CD33 EXPRESSION IS RESTRICTED TO CERTAIN LYMPHOID NEOPLASMS/

The authors examined the expression of myeloid antigens (MyAg): CD11b, CD13, CD14, CD15, and CD33 in 249 adults with lymphoid neoplasms usin g flow cytometric analysis. In this study, acute leukemia that was mye loperoxidase negative by light microscopy and had at least one lymphoi d antigen was defined as acute lymphoblastic leukemia (ALL). The patie nts were classified as follows: 6 with unclassified ALL, 35 early B pr ecursor ALL, 32 T-ALL, 25 B-cell chronic lymphocytic leukemia (B-CLL) and its variants, 24 B-cell non-Hodgkin's lymphoma (B-NHL), 7 plasma c ell disorders, 8 T-CLL, 2 adult T-cell leukemia, and 10 T-NHL, CD11b a nd CD15 were present in a wide range of lymphoid disorders irrespectiv e of B/T lineage and maturity. Unclassified ALL and phenotypically imm ature ALL frequently expressed CD13 and CD33, and occasionally express ed CD14. Among early B precursor ALL, CD13, and/or CD33 were significa ntly associated with the presence of stem cell marker CD34 and the chr omosomal abnormality t(9;22). In addition, ALL with deletion of chromo some 7 commonly expressed CD13 and CD33. Taken together, CD13 and/or C D33 positive ALL may originate from a multipotential stem cell. Among mature neoplasms, CD14 was frequently, and CD13 and CD33 were occasion ally expressed in B-cell, but not T-cell tumors. These results suggest that CD13, CD14, and CD33 are preferentially expressed in two types o f lymphoid neoplasms, namely undifferentiated ALL and mature B-cell ly mphoproliferative disorders.