[Characterization of the leukemic cell population in a patient with T-ALL at disease beginning and in recurrence: parallel changes in phenotypic and functional behavior]. / Charakterisierung der leukämischen Zellpopulation bei einem Patienten mit T-ALL im Krankheitsbeginn und im Rezidiv: Parallele Veränderungen im phänotypischen und funktionellen Verhalten.

The phenotypic and functional characteristics of the leukemic cells from one patient with a suppressor T-ALL were studied. At the time of diagnosis a high proportion of OKT8 positive (suppressor/cytotoxic) cells were identified which mediated strong suppressor activity to the differentiation of allogenic B-cells. A complete remission of 12 months duration was achieved by chemotherapy. In the relapse the marker analysis showed a dramatic decrease of the OKT8 positive cell fraction. Functionally the suppressor activity was completely lost indicating a close correlation between phenotype and functional activity also in a leukemic cell population.