Expression of interleukin-2 receptor on T cell chronic lymphocytic leukemia cells and their response to interleukin-2.
We analyzed peripheral blood leukemic cells from six patients with T cell chronic lymphocytic leukemia (T-CLL) with monoclonal antibodies including the anti-Tac antibody, which recognizes the receptor for interleukin 2 (IL 2). The patients were divided into two groups according to the reactivity of the monoclonal antibodies. Leukemic cells from three patients with T-CLL reacted with OKT3 and T4 but not T8, whereas those from the remaining three patients reacted with OKT3 and T8 but not T4. IL 2 receptor, which is expressed on activated T cells but not on resting T cells, was preferentially expressed on T4+ T-CLL cells. The IL 2 receptor on T4+ T-CLL cells was indistinguishable from that on normal activated T cells with respect to molecular weight and downregulation by the anti-Tac antibody. Moreover, fresh T4+ T-CLL cells, but not T8+ T-CLL cells, proliferated in response to exogenous IL 2 without prior activation, and this proliferation was inhibited by the anti-Tac antibody. These results suggest that malignant growth of T4+ T-CLL cells can be regulated by IL 2 not only in vitro but also in vivo.
Tsudo
M
M
Uchiyama
T
T
Umadome
H
H
Wano
Y
Y
Hori
T
T
Tamori
S
S
Uchino
H
H
Kita
K
K
Chiba
S
S
Mitsutani
S
S
D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism*; D007945:Leukemia, Lymphoid / Q000378:metabolism*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D008970:Molecular Weight; D011971:Receptors, Immunologic / Q000378:metabolism*; D015375:Receptors, Interleukin-2; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2