High serum levels of soluble interleukin 2 receptor in patients with B
chronic lymphocytic leukemia
G Semenzato, R Foa, C Agostini, R Zambello, L Trentin, F Vinante, F Benedetti, M Chilosi and G Pizzolo
By using an enzyme-linked immunosorbent assay, the presence of the soluble
form of the interleukin-2 receptor (sIL-2R) was evaluated in the peripheral
blood of 54 patients with B cell chronic lymphocytic leukemia (B-CLL).
Serum levels of sIL-2R were correlated with clinical features, relevant
hematologic and immunological data, and in some cases, with in vitro
functional studies. In 51 patients (94.4%), the levels of sIL-2R were
increased as compared with normal age-matched controls (1,781 U/mL +/- 231
v 276 U/mL +/- 26, respectively; P less than .001). Although this increase
was observed in all stages of the disease and independently of several
hematologic and immunologic parameters, a trend toward lower levels of
sIL-2R was documented in patients with a less-invasive disease. When the
values were correlated with the functional status of the residual T cell
population, it was found that patients with the lowest levels of sIL-2R
showed the best mitogenic response and helper capacity. It is suggested
that in B-CLL patients the high levels of serum sIL-2R, capable of binding
to its ligand, may block the T cell-produced IL-2, thus contributing toward
a defective physiological action by this lymphokine. In turn, this
defective availability of IL-2 may play a part in the abnormal
immunoregulation that is implicated in the hypogammaglobulinemia,
susceptibility to infections, and incidence of second neoplasias often
observed in this disease.
Volume 70,
Issue 2,
pp. 396-400,
08/01/1987
Copyright © 1987 by The American Society of Hematology
