Effect of immunosuppressive therapy on expression of tumor necrosis factor-α, interferon-γ, soluble Fas and T cell subsets in patients with aplastic anemia

Objective To investigate the effect of immunosuppressive therapy (IST) on the expression of serum tumor necrosis factor (TNF)-α, interferon-γ, soluble Fas (sFas) and peripheral blood T cell subsets in patients with aplastic anemia (AA). Methods From June 2016 to June 2018, a total of 50 patients with AA admitted to Rugao People′s Hospital were selected as study group. The patients in study group were (28.8±4.6) years old. There were 24 male and 26 female patients. There were 27 cases of severe aplastic anemia (SAA) and 23 cases of very severe aplastic anemia (VSAA). At the same time, a total of 50 healthy individuals who were (29.2±4.8) years old and underwent physical examination in the same hospital were selected as control group, randomly. There were 23 male and 27 female subjects. Patients in study group were treated with cyclosporine and antithymocyte globulin (ATG) for IST. After 28 weeks of treatment, the clinical efficacy of patients with AA was evaluated. The levels of serum TNF-α, interferon-γ, sFas and T cell subsets in peripheral blood before and after treatment in study group and the subjects in control group were examined at physical examination time. Independent sample t test was used to compare the expression levels of TNF-α, interferon-γ, sFas and the proportions and proportion ratios of T cell subsets of subjects in the 2 groups and AA patients before and after treatment. The study protocol was approved by the Ethical Review Board of Investigation in Human at Rugao People′s Hospital (Approval No. 2016LL018). Informed consents were obtained from all participants. Results ① After 28 weeks of IST, twenty two cases of AA patients in study group basically cured, twenty cases were relieved, and 8 cases were significantly improved. The total effective rate was 84% (42/50). ② Before treatment, serum TNF-α and interferon-γ levels in study group were (170.7±22.4) pg/mL and (76.9±5.9) pg/mL, respectively, and were significantly higher than those of (140.0±18.8) pg/mL and (52.4±4.8) pg/mL in control group, and the differences were statistically significant (t=7.423, P<0.001; t=22.777, P<0.001). Before treatment, serum sFas level in study group was (3.7±0.9) μg/L, and was significantly lower than that of (5.1±1.0) μg/L in control group, and the difference was statistically significant (t=7.358, P<0.001). Serum TNF-α and interferon-γ levels in study group after treatment were (152.5±20.7) pg/mL and (61.5±4.9) pg/mL, respectively, and were significantly lower than those of (170.7±22.4) pg/mL and (76.9±5.9) pg/mL before treatment, and the differences were statistically significant (t=4.220, P<0.001; t=14.199, P<0.001); serum sFas level was (4.9±1.0) μg/L, and was significantly higher than that of (3.7±0.9) μg/L before treatment, and the difference was statistically significant (t=6.307, P<0.001). ③ Proportions of CD3+ T cells, CD4+ T cells and CD4+ T cells/CD8+ T cells in study group were (61.5±5.2)%, (28.8±5.0)% and (1.2±0.4)%, respectively, and were significantly lower than those of (66.2±4.9)%, (42.1±5.3)% and (1.5±0.5)% in control group, and the differences were statistically significant (t=4.651, P<0.001; t=12.907, P<0.001; t=3.313, P=0.001). Proportion of CD8+ T cells was (31.5±5.0)%, and was significantly higher than that of (25.1±5.2)% in control group, and the difference was statistically significant (t=6.273, P<0.001). The proportions of CD3+ T cells, CD4+ T cells and CD4+ T cells/CD8+ T cells in study group after treatment were (64.9±5.0)%, (38.7±5.3)% and (1.4±0.5)%, respectively, and were significantly higher than those of (61.5±5.2)%, (28.8±5.0)% and (1.2±0.4)% before treatment, and the differences were statistically significant (t=3.333, P<0.001; t=9.608, P<0.001; t=2.209, P=0.030); proportion of CD8+ T cells was (27.7±5.2)%, and was significantly lower than that of (31.5±5.0)% before treatment, and the difference was statistically significant (t=3.725, P<0.001). Conclusions Expression levels of TNF-α, interferon-γ and proportion of CD8+ T cells in patients with AA were higher than those in healthy people, and the levels of sFas, proportions of CD3+ T cells, CD4+ cells and CD4+ T cells/CD8+ T cells were lower than those in healthy people. IST can significantly regulate the levels of serum TNF-α, interferon-γ, sFas and peripheral blood T cell subsets in patients with AA. Key words: Immunosuppression; Aplastic anemia; Tumor necrosis factor-alpha; Interferon-gamma; Soluble Fas