OBJECTIVETo study the changes of intracellular interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) expressions in children with acute lymphoblastic leukemia (ALL) at different stages, and to examine the correlation between IL-6 and IFN-gamma in ALL children.

METHODSThe levels of intracellular IL-6 and IFN-gamma in venous blood lymphocytes were detected by flow cytometry in 42 children with ALL at diagnosis and at remission stage. Twenty healthy children were used as the controls.

RESULTSThe intracellular IL-6 level in ALL children at diagnosis was 81.74+/-9.31, which was much higher than that in the Control group (5.67 +/- 0.96 ) (P < 0.01). The intracellular IFN-gamma level in ALL children (1.31 +/- 0.32) was significantly lower than that in the Control group (1.46 +/- 0.49) (P < 0.01). However, the intracellular IL-6 level (27.52 +/- 3.40) decreased remarkably in ALL patients at remission stage (P < 0.01), but was still higher than that in the Control group (P < 0.01). In contrast, the intracellular IFN-gamma level (1.97 +/- 0.72) increased noticeably in ALL patients at remission stage, which was higher than that at diagnosis and the Control group (P < 0.01). A negative correlation was found between the intracellular IL-6 and the IFN-gamma levels in ALL patients (r=-0.476, P < 0.05).

CONCLUSIONSIntracellular IL-6 and IFN-gamma levels may be used as the markers for monitoring the response to treatment in ALL patients. There is a negative correlation between intracellular IL-6 and IFN-gamma levels in ALL children.