Effect of HIV infection and antiretroviral therapy on hepatitis B virus (HBV)-specific T cell responses in patients who have resolved HBV infection

Coinfection with hepatitis B virus (HBV) is a common occurrence in human immunodeficiency virus (HIV) positive patients and an increasing cause of morbidity and mortality. The CD8(+) T cell response is critical for long-term control of HBV in patients resolving acute infection. Here, we examine the effect of HIV on HBV-specific CD8(+) T cell responses in patients who have resolved HBV infection. A cross-sectional study showed a reduction in HBV-specific CD8(+) T cell responses in HIV-positive, HBV-immune patients, compared with those in HIV-negative, HBV-immune patients. A longitudinal study of a subgroup of patients examined whether this attrition could be reversed by effective antiretroviral therapy. The introduction of highly active antiretroviral therapy ( HAART) resulted in reconstitution of some HBV-specific CD4(+) and CD8(+) T cell responses, in association with restoration of CD4(+) T cell counts. These data provide a mechanism to account for the observed impairment of control of HBV infection in the setting of HIV infection and support the ability of HAART to reconstitute functionally active T cell responses.