Studies of Immune Responses in Patients With Chronic Hepatitis B

The HBsAg (+) patients from National Taiwan University Hospital will be included. Screening for HLA haplotype will be performed by amplification refractory mutation system / PCR method. The HLA-A2 or HLA-A11 will be enrolled to the study group because these two haplotypes are the most ones in Taiwan. The other HLA haplotype HBV carriers will be enrolled as HLA-mismatch control. The disease spectra include inactive HBV carrier, CH-B, CH-B with AE (defined as ALT >= 5 X UNL), HBV-related LC, HBV-related HCCs.

HBsAg, anti-HBs, IgM anti-HBc, HBeAg, anti-HBe, anti-HCV, anti-HDV, anti-HIV will be determined by commercial enzyme immunoassay kits. The serum levels of HBV DNA and genotypes will be done by quantitative real-time PCR. Patients who are also infected with HDV or HCV or HIV will be excluded.

PBMCs will be isolated from heparinized blood samples by density gradient centrifugation on Ficoll-Hypaque. The PBMC will be washed with phosphate-buffered saline (PBS) and resuspended in T cell medium.

Analysis of HBV-specific CD8+ T cell responses will be done by flow cytometry using pentamer staining.

To analyze HBV-specific CD8+ T cells responses in patients with chronic HBV infection (prospective study). This part of the study is to clarify the role of HBV-specific T cell responses during the course of acute exacerbation of CH-B. Blood will be collected at four important time points.