RESUMEN
<p><b>OBJECTIVE</b>To explore the levels of circulating HBV specific CD8+ T cells in hepatitis B patients and analysis its clinical significance.</p><p><b>METHODS</b>HBV specific CD8+ T cells in whole blood samples of twenty-five acute hepatitis B patients, thirty-five chronic hepatitis B patients and ten healthy control were stained with pentamers complex of HLA-A2 and HBV core 18-27 peptide and counted by flow cytometry.</p><p><b>RESULTS</b>The medians of HBV core 18-27 specific CD8+ T cells quantities among total CD8+ cells were 2.93% (1.12% -0.63%) in 12 HLA-A2+ acute hepatitis B patients and 0.75% (< 0.01% - 1.76%) in 16 HLA-A2+ chronic hepatitis B patients respectively. There was showed a marked significant between the two groups (P < 0.01). The medians of HBV core 18-27 specific CD8+ T cells of 10 HLA-A2+ healthy control, 13 HLA-A2- acute hepatitis B patients and 19 HLA-A2- chronic hepatitis B patients were all lower than 0.02% separately.</p><p><b>CONCLUSION</b>HLA-peptides pentamers staining flow cytometry is a direct ex vivo method to detect the levels of circulating HBV specific CD8+ T cells which may be play a crucial role in complete clearance of HBV and relates to clinical consequence in hepatitis B patients.</p>