COMPOSITION OF PERIPHERAL-BLOOD LYMPHOCYTE POPULATIONS DURING DIFFERENT STAGES OF CHRONIC INFECTION WITH HEPATITIS-B VIRUS

To characterize the immunological populations associated with differen t stages of chronic infection with hepatitis B virus (HBV), we perform ed flow cytometric analyses on the peripheral blood leucocytes of 29 p atients with various forms of chronic hepatitis B, The clinical spectr um of the patients ranged from asymptomatic infections, in the presenc e of high virus production, to intermittent or recurrent exacerbations of liver injury alternating with relatively normal liver function. Pa tients with partial resolution of disease who experienced an initial a cute flare followed by prolonged seroconversion showed decreased perce ntages of CD3(+) cells during the seroconversion phase when levels of serum alanine transferase (ALT) had normalized. These CD3(+) cells wer e predominantly CD4(+) cells bearing the alpha beta(+) T-cell receptor (TCR). In addition, we saw an increase in CD4(+) and CD8(+) cells bea ring the gamma delta TCR in those patients who had seroconverted. No s ignificant differences were seen between any of the groups with respec t to percentage of cells with a naive (CD45RA) or memory (CD45RO) phen otype, or of cells displaying the activation markers CD38, HLA-DR or C D57. Longitudinal analyses of 15 patients failed to show any consisten t pattern of changes in the immunophenotypic profile during acute flar es and their resolution. Our results indicate that the turnover of cir culating T lymphocytes during the apparent quiescent phase of chronic infections is higher than that during acute exacerbations, suggesting an active immunosurveillance role of T-cell subpopulations in maintain ing low virus levels during seroconversion.