Flow cytometric analysis of expression of interleukin-2 receptor beta chain
(p70-75) on various leukemic cells
S Hoshino, K Oshimi, M Tsudo, M Miyasaka, M Teramura, M Masuda, T Motoji and H Mizoguchi
Department of Medicine, Tokyo Women's Medical College, Japan.
We analyzed the expression of the interleukin-2 receptor (IL-2R) beta chain
(p70-75) on various leukemic cells from 44 patients by flow cytometric
analysis using the IL-2R beta chain-specific monoclonal antibody (MoAb),
designated Mik-beta 1, which has been recently developed. Flow cytometric
analysis demonstrated the expression of the IL-2R beta chain on granular
lymphocytes (GLs) from all eight patients with granular lymphocyte
proliferative disorders (GLPDs), on adult T- cell leukemia (ATL) cells from
all three patients with ATL, and on T- cell acute lymphoblastic leukemia
(T-ALL) cells from one of three patients with T-ALL. Although GLs from all
the GLPD patients expressed the IL-2R beta chain alone and not the IL-2R
alpha chain (Tac-antigen: p55), ATL and T-ALL cells expressing the beta
chain coexpressed the alpha chain. In two of seven patients with common ALL
(cALL) and in both patients with B-cell chronic lymphocytic leukemia, the
leukemic cells expressed the alpha chain alone. Neither the alpha chain nor
the beta chain was expressed on leukemic cells from the remaining 28
patients, including all 18 patients with acute nonlymphocytic leukemia,
five of seven patients with cALL, all three patients with multiple myeloma,
and two of three patients with T-ALL. These results indicate that three
different forms of IL-2R chain expression exist on leukemic cells: the
alpha chain alone; the beta chain alone; and both the alpha and beta
chains. To examine whether the results obtained by flow cytometric analysis
actually reflect functional aspects of the expressed IL-2Rs, we studied the
specific binding of 125I-labeled IL-2 (125I-IL-2) to leukemic cells in 18
of the 44 patients. In addition, we performed 125I-IL-2 crosslinking
studies in seven patients. The results of IL-2R expression of both
125I-IL-2 binding assay and crosslinking studies were in agreement with
those obtained by flow cytometric analysis. These results indicate that
flow cytometric analysis using MoAbs, anti-Tac, and Mik-beta 1 is useful
for detecting the expression of the IL-2R chains.
Volume 76,
Issue 4,
pp. 767-774,
08/15/1990
Copyright © 1990 by The American Society of Hematology