Clinical Significance of Soluble Interleukin-2 Receptor in Patients with Acute Leukemia

Objective: Investigate the expression level and clinical significance of serum soluble interleukin-2 receptor (sIL-2R, sCD25) in patients with acute leukemia.

Methods: Serum sCD25 level were measured using enzyme linked immunosorbent assays (ELISA) in 97 acute leukemia patients and 10 healthy contrlols. Clinical and laboratory features, including bone marrow cellularity, white blood cell count (WBC), platelets (PLT), lactate dehydrogenase (LDH), serum ferritin (SF), erythrocyte sedimentation rate (ESR), as well as overall survival (OS) data were collected.

Results: (1) Serum sCD25 level of the newly diagnosed leukemia group was significantly higher than that of the control group (P<0.0001). (2) Among the newly diagnosed AML patients, serum sCD25 level of the M3 group was significantly lower than that of the M2 or non-M2/M3 group (P<0.05). In addition, serum sCD25 level of the low/intermediate risk (AML) or standard risk (ALL) group was lower than that of the high risk group (P<0.05). (3) Serum sCD25 level of the complete remission (CR) group was significantly lower than that of the newly diagnosed group (P<0.002). However, no significant decrease was found in serum sCD25 level of the relapsed/refractory group compared to that of the newly diagnosed group. (4) Serum sCD25 level in newly diagnosed patients was positively correlated with peripheral WBC, LDH and SF. (5) Furthermore, although OS of the low sCD25 level group (sCD25<2000pg/ml) was not significantly different compared to the intermediate sCD25 level group (2000≤sCD25≤4000pg/ml) (P=0.532), both that of the low or intermediate sCD25 level group were significantly superior to that of the high sCD25 level group (sCD25>4000pg/ml) (P<0.05).

Conclusion: Serum sCD25 levels have important clinical significance in evaluating disease activity, treatment outcomes and prognosis in patients with acute leukemia.