T lymphomas associated with human T-cell leukemia-lymphoma virus may show phenotypic and functional differences from adult T-cell leukemias.

We report phenotypic and functional characterization of lymph node cells from 27 patients with T lymphoma from the Nagasaki district of Japan. Nagasaki is one of several areas where adult T-cell leukemia is endemic, and sera from 18 of 23 patients examined (78.3%) were positive for antibody to adult T-cell leukemia-associated antigen. The majority of cases (24 of 27) showed the Leu-2a-, 3a+, MASO36c- phenotype similar to adult T-cell leukemia, but seemed to be subdivided into four groups according to the presence or absence of Leu-1 antigen and the receptor for sheep erythrocytes (SRBC). Eleven cases had both Leu-1 antigen and the receptor for SRBC (E-RFC+, Leu-1+, 2a-, 3a+), but 6 cases lacked Leu-1 antigen (E-RFC+, Leu-1-, 2a-, 3a+), 4 cases lacked receptors for SRBC (E-RFC-, Leu-1+, 2a-, 3a+), and 3 cases lacked both of these markers (E-RFC-, Leu-1-, 2a-, 3a+). The effects of lymph node T cells on pokeweed mitogen (PWM)-induced normal B-cell differentiation was studied in 10 cases. Lymph node T cells of 5 cases showed helper activity without any suppressor activity, and 2 cases showed suppressor activity with almost no detectable helper activity, similar to adult T-cell leukemia cells. Two other cases lacked particular functional effects. These results suggest the possibility that Leu-3a+ T-cell lymphoma may be functionally subdivided into at least two types, a helper type and a suppressor (adult T-cell leukemia) type.