To observe the changes of immune function in patients with immune thrombocytopenia (ITP).

From May 2016 to February 2017, 40 patients with ITP were enrolled at the Xiyuan Hospital and Dongfang Hospital. Twenty-four healthy persons were also included. The 40 ITP patients were classified into three groups: a chronic group (CG; n=22), a newly diagnostic group (NG; n=9), and a persistent group (PG; n=9). The expression of Th1, Th2, Th17, Treg, and Breg was detected by flow cytometry. Wilcoxon test was used to analyze the difference between the ITP group and the control group (COG), while Kruskal-Wallis test was used for multi-group comparisons.

In comparison with the COG, the expression of Th1 [(16.88±9.02)% vs (8.83±5.3)%, Z=-3.753, P=0.001] and Th1/Th2 ratio [(10.98±9.08)% vs (4.61±3.13)%, Z=-3.596, P=0.001] in patients with ITP were higher, while the levels of Th17 [(1.02±0.37)% vs (1.41±0.38)%, Z=-3.141, P=0.002], Th17/Treg [(1.01±0.37)% vs (0.3±0.05)%, Z=-1.693, P=0.009], and Breg [(1.35±1.37)% vs (2.07±0.86)%, Z=-5.963, P=0.001)] were significantly lower. The expression of Th1 in the CG [(18.75±10.38)%], NG [(16.12±7.72)%], or PG [(13.11±3.83)%] was significantly higher than that in the COG [(8.8±5.3)%, Z=14.83, P=0.002]. Th1/Th2 ratio in the CG [(12.03±10.65)%], NG [(11.63±8.77)%], or PG [(7.77±3.43)%] was significantly higher than that in the COG [(4.61±3.13)%, Z=13.363, P=0.004]. The expression of Th17 in the CG [(1.07±0.33)%], NG [(0.91±0.28)%], or PG [(0.98±0.54)%] was significantly lower than that in the COG [(1.41±0.38)%, Z=10.040, P=0.018]. Th17/Treg ratio in the CG [(0.18±0.01)%], NG [(0.15±0.07)%], or PG [(0.16±0.09)%] was significantly lower than that in the COG [(0.3±0.05)%, Z=3.200, P=0.03]. The expression of Breg in the CG [(1.26±1.54)%], NG [(1.77±1.58)%], or PG [(1.14±0.52)%] was also significantly lower than that in the COG [(2.07±0.86)%, Z=35.731, P=0.001]. There was no difference in the expression of Th2 or Treg between patients with ITP and healthy persons (P>0.05).

Both T and B cell dysfunctions are involved in the pathogenesis of ITP. T cell dysfunction manifests mainly as Th1/Th2 and Th17/Treg imbalance. There is no significant difference in immune cells between different subtypes of ITP patients.