Change and significance of Th22 cells in patients with aplastic anemia

Objective To explore the proportion of Th22 cells in peripheral blood of patients with aplastic anemia (A A) and evaluate its significance. Methods From January 2011 to June 2012,a total of 47 AA patients were recruited and divided into 4 groups:severe aplastic anemia (SAA) pretherapy (group A,n=11),non-severe aplastic anemia (NSA A) pre-therapy (group B,n=12),SAA post-therapy (group C,n=12), NSAA post-therapy (group D,n=12) and healthy donor controls (n=12).The proportion of Th22 cells in peripheral blood of each group was evaluated by flow cytometry.The cytokines interleukin-22 (IL-22), transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were measured by ELISA.And the level of IL-22 mRNA was examined by reverse transcription-PCR (RT-PCR). Results The percentage of Th22 cells and the level of IL-22, TNF-α, IL-6 and IL-22 mRNA in group A (4.3%±1.4%, (57±17) ng/ L, (497±123) ng/L, (323±88) ng/L, 1.65±0.51) and group C (2.6%±0.6%, (34±10) ng/L, (314±79) ng/L, (187±45) ng/L, 0.92±0.28) were significantly higher than that in control group (1.2%±0.3%, (19±6) ng/L, (228±50) ng/L, (134±26) ng/L, 0.47±0.09,all P<0.05).The percentage of Th22 cells and the level of IL-22, TNF-α, IL-6 and IL-22 mRNA in group A were higher than those in group C (all P<0.05).NSAA patients had similar results.The percentage of Th22 cells and the level of IL-22, TNF-α, IL-6 and IL-22 mRNA in group A were higher than those in group B (all P<0.05).But the level of TGF-βin groups A and C were significantly lower than that in control group ((3.4±1.1) and (5.8±1.7) vs (9.7±2.8) ng/L,P<0.05).And the level of TGF-βin group A was lower than that of group B (P<0.05). Conclusions The number of Th22 cells is elevated in AA patients.Th22 cells may be positively correlated with the development of AA.And a higher level of TNF-α, IL-6 and a lower level of TGF-βpromote the differentiation of Th22 cells. Key words: Anemia, aplastic; Interleukins; Transforming growth factors; Th22 cells