The significance of change of Th22 cells in patients with acute lymphoblastic leukemia

OBJECTIVE: To investigate the proportion of Th22 cells in peripheral blood of patients with acute lymphoblastic leukemia (ALL) and evaluate its significance. METHODS: The proportions of Th22 cells in peripheral blood of B-ALL and T-ALL patients before therapy (group 1), B-ALL and T-ALL patients in complete remission (ALL-CR, group 2) and healthy donors (group 3) were evaluated by flow cytometry. The cytokines IL-22, TGF-β, TNF-α and IL-6 in peripheral blood of each group were measured by enzyme-linked immunosorbent assay (ELISA). The levels of IL-22 mRNA in peripheral blood mononuclear cells of each group were examined by reverse transcription-PCR (RT-PCR). RESULTS: The percentages of Th22 cells and the levels of IL-22, TNF-α, IL-6 and IL-22 mRNA in B-ALL and T-ALL patients before therapy were (0.44 ± 0.10)%, (10.9 ± 3.4) ng/L, (110.7 ± 26.5) ng/L, (60.2 ± 13.8) ng/L, 0.17 ± 0.04 and (0.46 ± 0.11)%, (11.2 ± 3.5) ng/L, (114.6 ± 27.0) ng/L, (58.7 ± 12.4) ng/L, 0.19 ± 0.04, respectively; Which in B-ALL and T-ALL patients in complete remission were(0.59 ± 0.15)%, (14.3 ± 4.1) ng/L, (142.5 ± 32.7) ng/L, (83.7 ± 18.9) ng/L, 0.25 ± 0.06 and(0.60 ± 0.15)%, (14.6 ± 4.3) ng/L, (140.4 ± 31.4) ng/L, (81.4 ± 18.2) ng/L, 0.26 ± 0.06, significantly lower than those in healthy donors \[(1.24 ± 0.31)%, (19.7 ± 6.6) ng/L, (238.3 ± 50.4) ng/L, (138.0 ± 27.1) ng/L, 0.49 ± 0.09\] (P 0.05). But the levels of TGF-β in B-ALL and T-ALL patients before therapy \[(30.6 ± 8.2) ng/L, (31.4 ± 8.8) ng/L\] and in complete remission \[(24.2 ± 5.8) ng/L, (25.1 ± 6.1) ng/L\] were significantly higher than those in group 3\[(9.6 ± 2.8) ng/L\] (P 0.05). CONCLUSION: Both the number and function of Th22 cells reduced in ALL patients. Th22 cells might be negatively correlated with ALL progression. The lower levels of TNF-α and IL-6, and overexpression of TGF-β in ALL patients might suppress the differentiation of Th22 cells.