[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 < 0.01). The percentages of Th22 cells and the levels of IL-22, TNF-α, IL-6 and IL-22 mRNA in group l were lower than those in group 2 (P < 0.05), there was not significant difference between B-ALL and T-ALL (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 < 0.01). However, the level of TGF-β in group 1 was higher than that of group 2 (P < 0.05), there was not significant difference between B-ALL and T-ALL (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.