Abstract:

Objective To investigate the expression of Th1 and Th2 cytokines in peripheral blood of children with acute leukemia, and explore its roles in the onset and chemotherapy of leukemia. Methods Seventy-eight children with acute leukemia were enrolled, including 53 cases of acute lymphoblastic leukemia (ALL) and 25 cases of acute nonlymphocytic leukemia (ANLL). Twenty-one cases were newly diagnosed (newly diagnosed group). All cases were divided into complete remission group 1 (n=42, duration of complete remission<12 months) and complete remission group 2 (n=36, duration of complete remission ≥12 months) after chemotherapy. Another 30 healthy children were served as normal controls. The percentages of Th1 (IL-2 and IFNγ) and Th2 (IL-4) cytokines in peripheral blood were detected by flow cytometry. Results The levels of IL-2, IFNγ and IL-4 in newly diagnosed group were significantly different from those in normal control group and complete remission groups before treatment (P<0.05). The levels of IL-2, IFNγ and IL-4 in newly diagnosed group significantly improved after treatment, which were not significantly different from those in normal control group (P>0.05). The levels of IL-2 and IFNγ in complete remission group 1 were significantly higher than those in complete remission group 2 (P<0.05), while there was no significant difference in levels of IL-4 between these two groups (P>0.05), and the levels of IL-2, IFNγ and IL-4 in these two groups were not significantly different from those in normal control group (P>0.05). There was no significant difference in the levels of IL-2, IFNγ and IL-4 between patients with ALL and ANLL (P>0.05). Conclusion Th1 and Th2 cytokines may play a role in the process of acute leukemia, and they may produce a similar effect in ALL and ANLL. Along with the prolongation of duration of complete remission, the immunologic function gradually recovers, but it is disturbed again latter, which may be related to immunosuppression secondary to chemotherapy.

Key words: acute leukemia, helper T cell, flow cytometry, childhood