Increased intrahepatic apoptosis but reduced immune activation in HIV-HBV co-infected patients with advanced immunosuppression.

ABSTRACT

OBJECTIVE: to determine if intrahepatic immune activation is increased in HIV-hepatitis B virus (HBV) co-infected patients compared to HBV mono-infected patients and whether this reduced following HBV-active antiretroviral therapy (ART) in HIV-HBV co-infected patients. DESIGN: Case-control observational study. METHODS: we examined liver biopsies for markers of T-cell and monocyte infiltration and activation, natural killer cells, hepatic stellate cell (HSC) activation (staining for alpha smooth muscle actin) and apoptosis [using terminal dUTP nick-end labelling (TUNEL)] in treatment-naive Asian HIV-HBV co-infected (n = 16) and HBV mono-infected patients matched for age and HBV e-antigen status (n = 16). Liver biopsies from a subset of co-infected patients (n = 15) were also compared prior to and following 48 weeks of HBV-active ART. RESULTS: HIV-HBV co-infected patients had a median CD4 T-cell count of 25 cells/microl and lower alanine aminotransferase levels than HBV mono-infected patients (P = 0.03). In HIV-HBV co-infected patients, hepatocyte apoptosis was increased (P = 0.04) but there were fewer intrahepatic CD4 and CD8 T cells (P < 0.001), lower activation of intrahepatic T cells, Kupffer cells and HSC (P = 0.002, 0.008 and < 0.001, respectively). Following ART, there was a significant decrease in intrahepatic HBsAg staining (P = 0.04) and Kupffer cell activation (P = 0.003). CONCLUSIONS: we found no evidence of increased intrahepatic mononuclear and HSC activation in this cohort of HIV-HBV co-infected individuals with advanced immune suppression. An increase in intra-hepatic apoptosis in HIV-HBV co-infected individuals may potentially contribute to accelerated fibrosis in this setting.