Interleukin-2 receptor beta-chain (p70-75) expressed on leukemic cells from adult T cell leukemia patients.
To determine whether the interleukin-2 receptor (IL-2R) beta-chain (p70-75) is expressed on leukemic cells from patients with adult T cell leukemia (ATL) as well as alpha-chain (p55, Tac), we performed radiolabeled interleukin-2 (IL-2) binding assay, chemical crosslinking of radiolabeled IL-2 and flow cytometric analysis using a newly-developed anti-IL-2R beta-chain antibody. The results showed that leukemic cells from all the 12 ATL patients we examined expressed the IL-2R beta-chain together with the alpha-chain whereas there was no detectable beta-chain expression on unstimulated peripheral blood CD4(+) T cells from healthy volunteers. Southern blot analysis revealed that this abnormal expression was not caused by the structural change of IL-2R beta-chain gene. Though leukemic cells from all ATL patients examined expressed high-affinity IL-2Rs, leukemic cells from only 25% of all ATL patients proliferated in response to IL-2. These results showing abnormal expression of IL-2R beta-chain on leukemic cells from ATL patients (ATL cells) suggest a close association between HTLV-I infection and abnormal beta-chain expression as well as alpha-chain expression.
Kodaka
T
T
First Division of Internal Medicine, Faculty of Medicine, Kyoto University.
Uchiyama
T
T
Ishikawa
T
T
Kamio
M
M
Onishi
R
R
Itoh
K
K
Hori
T
T
Uchino
H
H
Tsudo
M
M
Araki
K
K
D000368:Aged; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D015139:Blotting, Southern; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens; D002455:Cell Division; D003432:Cross-Linking Reagents; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism; D015458:Leukemia, T-Cell / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000378:metabolism*
D000945:Antigens, Differentiation, T-Lymphocyte; D015704:CD4 Antigens; D016827:CD8 Antigens; D003432:Cross-Linking Reagents; D007376:Interleukin-2; D015375:Receptors, Interleukin-2