Changes of regulatory T cell proportion and activity in the patients with acute liver failure

Abstract

Objective To explore the changes of regulatory T (Treg) cell proportion and activity in peripheral blood of patients with acute liver failure (ALF).Methods Twenty patients with ALF and 10 healthy controls were selected in this study.Peripheral blood mononuclear cells (PBMCs) were obtained by using density gradient centrifugation.The proportion of CD4 + CD25 + CD127low Treg cells in the CD4 + cells was detected by using flow cytometry in PBMCs of enrolled cases.The immune activity of Treg cells isolated from PBMCs was observed by using a suppression assay of allogeneic mixed lymphocyte response (MLR).In addition,the levels of high sensitivity C reactive protein (hsCRP),erythrocyte sedimentation rate (ESR) and immunoglobulin in peripheral blood were also detected.Results The patients with ALF had a significantly lower percentage of Treg cells in CD4 + T ceils in PBMCs than healthy controls [(4.20 ±1.34) ％ vs.(8.34 ± 0.89) ％,t =8.81,P ＜ 0.01].The suppressing homologous PBMCs proliferation ability of Treg cells isolated from the patients with ALF was significantly weakened in MLR [cpm =(21.48::4.14) x 103],which had a statistically significant difference compared with healthy controls [cpm =(6.32±1.18) ×103,t=11.26,P＜0.01].The levels of hsCRP,ESR and immunoglobulin in peripheral blood in the patients with ALF were significantly higher than in healthy controls (P ＜ 0.05).The percentage of Treg cells were negatively correlated with hsCRP and IgG (r =-0.634,P ＜ 0.01 ; r =-0.596,P ＜ 0.01).Conclusion There is a decrease in both quantity and activity of Treg cells in the patients with ALF.Treg cells and other immuno-rcgulation factors may play an important role in the pathogenesis of ALF. Key words: Acute liver failure; Regulatory T cell; Immunoregulation