T-lymphocyte subpopulations in chronic lymphocytic leukemia: a quantitative and functional study.

In the peripheral blood of patients with chronic B‐cell lymphocytic leukemia (B‐CLL) absolute numbers of E‐rosetting lymphocytes were increased. The proportions of TG and TM cell subsets were analyzed, as were their effects on the pokeweed mitogen (PWM)‐dependent differentiation of normal allogenic B cells or of autologous leukemic cells. The TG lymphocyte subset was further studied for its cytotoxic activity in antibody‐dependent cellular cytotoxicity (ADCC). A marked increase both in percentages and in absolute numbers of TG cells was found. TM lymphocytes percentages were normal, but because of the T lymphocytosis occurring in all patients, the absolute numbers of TM were increased. TM and TG subsets showed helper and suppressor activity, respectively, in PWM‐induced B‐cell differentiation. TG cells displayed effector cell activity in ADCC. The results provide further evidence that T lymphocytes from patients with B‐CLL are functionally normal. However, a noticeable increase of the T‐cell subset having suppressor and cytotoxic activity in ADCC was observed. This may be the consequence of a normal immune reaction to the leukemic population. Copyright © 1981 American Cancer Society