Study On Phenotype And Function Of CD8~+T Cells In Chronic Liver Diseases

Objective:(1)The purpose of this study was to investigate whether liver fibrosis would worsen after chronic hepatitis B(CHB)complicated with non-alcoholic fatty liver diseases(NAFLD)and the correlation between the expression of NKG2A on CD8~+T cells in peripheral blood.(2)To investigate the correlation between CD8~+T cell function inhibition and CD4~+Treg cells in patients with hepatocellular carcinoma(HCC).Methods:(1)Peripheral blood mononuclear cells(PBMCs)were obtained from healthy controls,CHB patients,CHB with NAFLD patients and HCC patients by density gradient centrifugation.(2)Use flow cytometry(FACS)to detect the phenotype and function of CD8~+T cells and CD4~+Treg cells.(3)Serum samples from CHB patients and CHB with NAFLD patients were collected for detection of biochemical indexes and markers of liver fibrosis.(4)Hepatic tissues of CHB patients and CHB with NAFLD patients were collected for immunohistochemical staining analysis,and the difference in the number of NKG2A positive cells between the two groups was counted.(5)Clinical data of CHB patients and CHB with NAFLD patients were collected for liver biospy and Fibroscan detection.Results:(1)Compared with healthy controls and CHB patients,the expression of NKG2A on CD8~+T cells in the peripheral blood of CHB with NAFLD patients was specificity decreased.(2)The cytokine production on CD8~+T cells in peripheral blood of CHB with NAFLD patients was higher than that of CHB patients.(3)The expression of NKG2A on CD8~+T cells in CHB with NAFLD patients decreased with the increase of the degree of fibrosis.(4)The indexes of liver injury and fibrosis in serum of CHB patients with moderate fatty liver were higher than those of CHB patients.(5)The percentages of NKG2A~+CD8~+T cells in CHB patients with moderate fatty liver disease was lower than that in CHB patients.(6)The expression of NKG2A on CD8~+T cells in CHB patients with moderate fatty liver is negatively correlated with Fibroscan LSM value.(7)The expression of NKG2A on CD8~+T cells in CHB patients with moderate fatty liver was negatively correlated with liver fibrosis indexes in serum.(8)The inhibitory molecules on CD8~+T cells were highly expressed in the peripheral blood of HCC patients,and the cytokine secretion function in this group was lower than that in healthy controls.(9)The expression of TIGIT on CD8~+T cells in peripheral blood of HCC patients was higher than that of healthy people,and was positively correlated with both CD4~+Treg cells and IL-10~+CD4~+Treg cells.Conclusions:(1)The expression of NKG2A on CD8~+T cells in the peripheral blood of CHB with NAFLD patients was lower than that in the CHB patients.Based on the serological and Fibroscan data,it was found that the low expression of NKG2A on CD8~+T cells was correlated with the aggravation of liver fibrosis.It is suggested that the expression of NKG2A can be specifically increased in subsequent clinical treatment,so as to prevent the further aggravation of liver fibrosis,which provides a new idea for the clinical treatment of CHB with NAFLD patients.(2)The expression of TIGIT on CD8~+T cells in peripheral blood of HCC patients was positively correlated with both CD4~+Treg and IL-10~+CD4~+Treg cells,and the latter was also positively correlated with IL-10~+CD8~+T cells,suggesting that as an emerging immunosuppressant,TIGIT may be due to the inhibitory effect of CD4~+Treg established through IL-10 on CD8~+T cells.