Reaserch For The Relationship Of Indole Amines 2, 3-Dioxide Enzyme (IDO) And Immune Tolerance In HBV

Objective Recent studies have found, indoleamines-2,3 -dioxide enzyme (IDO) plays an important role in immune regulation,may be one of the important target to break the immune tolerance to hepatitis B,but the specific mechanism is not clear.To observe the correlation between the expression of IDO and the viral load of hepatitis B virus as well as T lymphocyte subsets and investigate the role and mechanism of IDO in immune tolerance of CHB, so as to provide a novel approach for reestablishment of active immunity.Methods 1.Case selectionTest Group: Hepatobiliary Surgery of my Hospital from September 2007 to January 2008, 50 cases of patients with chronic hepatitis B, age 28 ~ 65 years of age (43.9±56.1) years;male 38 cases,female 12 cases;course of 1 month to 30 years, median 125 months. Control group: Medical center of my hospital over the same period 50 cases of healthy persons,aged 18 ~ 70 years old; (33.9±68.1) years;male 28 cases,female 22 cases.Exclusion criteria: <18 or> 80 years old, who have received hormone therapy, hepatitis B patients received antiviral therapy two weeks ago, combined HCV infection, those with immune deficiency diseases, blood diseases, the body has infected lesions, including biliary infection, without the patient's consent.1. Specimen collection and processing methodsCollected the peripheral blood lymphocytes and serum from 50 cases of chronic hepatitis B patients,frozen at -80℃under test, while collecting the peripheral blood lymphocytes and serum from 50 cases of healthy persons in the same period ,as the normal control group. Detected the IDO mRNA expression of two groups of specimens lymphocyte by RT-PCR; Detected the IDO Protein quantification of two groups of specimens lymphocyte by Western-Blot;Detected the IDO activity of two groups of specimens serum by RP-HPLC; Detected the HBV-DNA of test group specimens serum by Quantitative immunofluorescence method; Detected the Function of T-lymphocyte subsets by Flow cytometry. ALT data was from the medical record of test group.Results In CHB patients, the mRNA, protein and activity of IDO were all significantly more than those in control group [mRNA: (2.110±0.615)×103 vs (0.143±0.026)×103; protein: 0.22±0.06 vs 0.02±0.0017; activity: 26.07±8.12 vs 4.98±1.65; P<0.05].1. IDO mRNA was positive correlated with HBV viral load (r=0.502, P<0.001) and ALT (r=0.65, P<0.01). 2. In test group (CD4: 28.66±13.92, CD8: 21.06±6.05, CD4/CD8: 1.3±0.35) CD4 (+) T cells and CD8 (+) T cell percentage and CD4/CD8 ratio was significantly lower than the control group ( CD4: 49.80±10.68, CD8: 29.90±2.53, CD4/CD8: 1.7±0.65), P<0.05].3. IDO mRNA, protein and activity were negative correlated with CD4(+) T cells (r=-0.622, -0.682, -0.549 respectively, P<0.05), CD8 (+) T cells(r=-0.487, -367, -294 respectively, P<0.05)and the ratio of CD4/CD8(r=-0.426, -0.533, -0.397 respectively, P<0.05)as well.Conclusion IDO closely correlates HBV viral load and responsible for the immunotolerance against HBV. Deletion of IDO could be a novel approach to break tolerance in CHB, and provide a new way of thinking for reconstruction of the body active immunization.