[Acute lymphocytic leukemia having surface phenotype of CD 2 and NKH-1 with rapid clinical course]

Abnormal expansion of large granular lymphocytes (LGLs) was observed in peripheral blood and bone marrow in a 28-year-old man. He had general lymphadenopathy and splenomegaly. Surface phenotypical analysis of LGLs showed that these LGLs express CD 2, Ia and NKH-1 but not express CD 3, CD 4, CD 8 and Leu 7. Cytochemical analysis of these LGLs revealed positive acid phosphatase and beta-glucuronidase reaction but negative alpha-naphthyl acetate esterase reaction. These LGLs showed very weak NK activity against only MOLT-4 but showed no cytotoxic activity against K 562. An beta-receptor gene rearrangement of human T-cell receptor was not found by Southern blot analysis. Rapid and fetal clinical course with the results of theses analytical studies showed that this case is highly suggestive of acute leukemia of LGLs which is committed to NK cell lineage.