Leu 7+, Leu 11a- acute T-lymphoblastic leukemia having low K cell activity and no NK cell activity

The phenotypic and functional features of the leukemic blasts from a child with T-acute lymphoblastic leukemia (T-ALL) were studied. The leukemic cells lacked the usual markers of T-cell lineage (T3-, T11-, E-sheep-) although they displayed some T-lymphocyte markers (T6+, T8+, T9+, T10+) and were T gamma-. Furthermore, these cells had a strong reaction with anti-Leu 7 but were negative to anti-Leu 11a antibody and exhibited low K cell activity, no NK activity, and showed virtually no response to PHA. These leukemic cells probably represented the leukemic counterpart of the Leu 7+, Leu 11a- subset that has been demonstrated in the peripheral blood of normal individuals.