The Significance Of CD4+CD25+regulatory T Cells In The Peripheral Blood Of Chronic Hepatitis B Patients

AIM: To investigate the frequency of CD4+CD25+regulatory T cell (Treg) in peripheral blood of patients with chronic hepatitis B (CHB),and patients with chronic severe hepatitis B (CSHB) experienced artificial liver treatment.METHODS: Peripheral blood mononuclear cell (PBMC)from 19 patients with CHB,28 with CSHB, 19 hepatitis B carriers,and 19 health controls was analyzed for Treg frequency by Flow cytometry.The expression of FOXP3 protein in PBMC was examined by immunohistochemistry.The correlation between Treg frequency and total bilirubin (TBIL),prothrombin activity (PTA) or HBV-DNA was also analyzed.RESULTS:The results were evaluated by CD4+CD25+regulatory T cell/PBMC.Treg frequency in CHB, CSHB, hepatitis B carriers and health controls was (0.50±0.34)%, (0.53±0.37)%, (1.67±0.87)%, (4.80±1.50)% respectively.(1) The count of CD4+CD25+ regulatory T cell of CSHB (4.80±1.50)% exceed that of CHB (1.67±0.87)%,hepatitis B carriers (0.59±0.37)%and normal controls(0.50±0.34)%significantly(P<0.01).The same result could be found between CHB and hepatitis B carriers as well as normal controls (P<0.01),but not in hepatitis B carriers and normal controls (P>0.05). Amount CHB,the count of CD4+CD25+regulatory T cell was 4.00±0.90, 1.03±0.15,0.48±0.30 respectively in severe,moderate and mild chronic hepatitis(P<0.01),and there was significance difference between moderate and mild chronic hepatitis(P<0.01).(2)The expression of FOXP3 protein also been increased in CSHB and CHB,which was parallel with the variation of the count of CD4+CD25+ regulatory T cell. (3)The variation of CD4+CD25+ regulatory T cell been correlated positively with that of TBIL(r=0.43,P<0.01) and correlated reversely with that of PTA(r=-0.57,P<0.05).There was no correlation between the variation of CD4+CD25+ regulatory T cell and that of HBV-DNA level (r=0.22, P>0.05).(4)The level of CD4+CD25+ regulatory T cell been increased significantly after artificial liver treatment (5.12±1.37)% VS (9.35±2.41)%,P<0.05).CONCLUSION: (1)The level of CD4+CD25+ regulatory T cell been up-regulated significantly in CSHB and CHB, and also been associated with the pathogenetic condition.lt indicated that the variation of CD4+CD25+ regulatory T cell is the result of the excessive immune and inflammatory reaction.However,the function of CD4+CD25+ regulatory T cell in CSHB and CHB may be defective.(2)The expression of FOXP3 protein also been increased in CSHB patients and CHB patients,which is parallel with the variation of the count of CD4+CD25+ regulatory T cell.But there is no correlation between the variation of CD4+CD25+ regulatory T cell and FOXP3.(3)The CD4+CD25+ regulatory T cell may play an important role in the process of artificial liver treatment.lt is possible for the CD4+CD25+ regulatory T cell to keep the homeostasis of internal environment of the body and immune tolerance.