Cellular Immune Response In Different Phases Of Chronic HBV Infection And Its Relationship With Virus Clearance

ObjectiveTo study cellular immune response in different phases of chronic HBV infection and its relationship with virus clearance.MethodsPeripheral blood T-cell subsets of 50 cases with chronic HBV infection detected by flow cytometry .Liver biopsy were performed in 40 of these cases, CD4+, CD8+ cells were detected in liver biopsy by immunohistochemical technology. Liver tissue HBV-DNA were detected by real-time fluorescence quantitative PCR.10 normal liver tissues were from hepatic haemangioma patient.Results1. Different composition of peripheral blood T cell subsets in Chronic HBV infection and normal control group.The difference between group with chronic HBV infection and normal group was not significant (P> 0.05). According to the load of HBV-DNA,the group with chronic HBV infection was divided into HBV-DNA positive and HBV-DNA negative two groups: The percentage of CD4 + T cell and CD4/CD8 ratio in group of HBV-DNA positive are significantly lower than them in group of HBV-DNA negative and normal group(P<0.05,P <0.01, P <0.05,P<0.05).No significant difference was found between group of HBV-DNA negative and normal group.2. Different composition of peripheral blood T cell subsets in different phases of Chronic HBV infection.The percentage of CD4+ T cell and CD4/CD8 ratio were significantly different between immune tolerance phase, immune clearance phase, inactive phase, reactive phase and normal control group(P <0.05, P <0.05).While no significant difference was seen in the percentage of CD3+ T cell and CD8+ T cell . Further comparison within groups, we found that: percentage of CD4+ T cell and CD4/CD8 ratio in immune clearance phase were significantly lower than it in inactive group(P<0.05, P <0.05); percentage of CD4+ T cell and CD4/CD8 ratio of immune clearance phase and immune tolerance phase were significantly lower than them in normal control group(P <0.01, P <0.05, P <0.05, P <0.05). No significant difference was found between other groups(P>0.05).3. Correlation analysis between peripheral blood T cell subsets and HBV-DNA load in peripheral blood and in liver.The relationship between CD4/CD8 ratio in peripheral blood and HBV-DNA load in peripheral blood is negative correlation (r = -0.308, P <0.05 ). No correlation was found between the percentage of CD3+,CD4+,CD8+ T cell and HBV-DNA load. No correlation was found between peripheral blood T cell subsets and HBV-DNA load in liver.No correlation was found between peripheral blood T cell subsets and HBV-DNA load in different phases of chronic HBV infection.4. Distribution of CD4, CD8 positive cells in liver tissue.A few of CD4, CD8 positive cells were seen in normal liver;CD4 positive cells mainly gathered in portal area and CD8 positive cells were mainly gathered in portal areas and surrounding inflammatory liver cells.5. Expression of CD4+, CD8+ cells in liver with different levels of HBV-DNA replication.CD4+, CD8+ cells in liver of chronic HBV infection were significantly more than them in normal liver(P <0.01, P <0.01). CD4+, CD8+ cells in liver of group HBV-DNA positive significantly more than them in normal liver(P<0.001,P<0.001), also more than them in HBV-DNA negative group, but there was no significant difference(P> 0.05, P>0.05);CD8+ cells in liver of HBV-DNA negative significantly more than it in normal liver(P<0.01), but there was no significant difference in the expression of CD4+ cells (P>0.05).6. Expression of CD4+ cells in different phases of chronic HBV infection.CD4+ cells in immune clearance phase, inactive phase and reactive phases were significantly more than it in normal control group(P<0.001). CD4+ cells in immune tolerance phase was significantly lower than it in immune clearance and reactive phase(P<0.05,P<0.01).No significant difference was found between other groups(P>0.05).7. Expression of CD8+ cells in different phases of chronic HBV infection.Expression of CD8+ cells in four different phases of chronic HBV infection were more than it in normal control group (P<0.05, P<0.05, P<0.01 P<0.01).Expression of CD8+ cells in immune tolerance was significantly lower than it in reactive phase(P <0.05).There was no significant difference was found between other groups.8. Immune state of immune active phase (immune clearance phase and reactive phase).We found that CD4+, CD8+ cells was significantly more than it in immune tolerance (P<0.01,P<0.05), CD4+ cells of this phase was significantly more than it in inactive phase(P<0.05), CD8+ cells of this phase was more than it in inactive phase, but there was no significant difference (P>0.05).There was negative correlation between percentage of CD4+ T cell and HBV-DNA load in peripheral blood(r =- 0.481, P <0.05). There was negative correlation between CD4/CD8 ratio of peripheral blood and HBV-DNA load in liver in group with ALT higher than 2×ULN(r =- 0.829, P <0.05). The difference was absent in group with ALT lower than 2×ULN.10. Spearman correlation analysis between HBV-DNA load in peripheral blood and in liver. It is significant positive correlation (r = 0.779, P <0.001). 11. HBV-DNA detection in liver tissue and serum. When serum HBV-DNA positive, HBV-DNA in liver tissue can be detected;while HBV-DNA can still be detected in liver tissue in eight cases of inactive phase with serum HBV-DNA negative.Conclusion1.Immune response in chronic HBV infection was dysfunction both in body and liver, HBV-DNA replication aggravated this change, we found percentage of CD4+ T cell and CD4/CD8 ratio of peripheral blood in HBV-DNA positive group significantly lower than them in negative group and normal control, infiltration of CD4+,CD8+ cells in liver of HBV-DNA positive group was significantly more than normal group.2. The immune state was different both in body and liver at different phases of chronic HBV infection. Peripheral blood CD4+ T cell percentage and CD4/CD8 ratio in immune clearance phase was significantly lower than inactive phase, intrahepatic CD4+, CD8+ cells in immune active phase were more than immune tolerance and inactive phase.3. The decrease of CD4+ T cells is not in favor of viral clearance, and the persistently high level virus replication may affect the proliferation of CD4+ T cell. There was negative correlation between percentage of CD4+ T cells and HBV-DNA load in peripheral blood in immune active phase, significantly negative correlation was found between CD4/CD8 ratio of peripheral blood and HBV-DNA load in liver tissue in group with ALT was 2 times higher than the upper limit of normal.4.HBV-DNA quantitative of liver tissue can more accurately reflect the level of viral replication than serum HBV-DNA quantitative.