Direct, help-independent priming of CD8+ T cells by AAV-transduced hepatocytes

Both HBV and HCV frequently establish chronic infection, raising the question whether T cells are poorly primed in the liver. To determine the role of different cell types in the activation of CD8+ T cells against hepatocellular antigens, we used an Adeno-Associated Virus to deliver ovalbumin to hepatocytes. In contrast to CD8+ T cells, CD4+ T cells were not activated. The CD8+ T cells were activated even in the absence of endogenous CD4+ T cells; however in the liver these cells were high in PD-1 and low in CD127. Chimera experiments revealed that these CD8+ T cells were activated on a solid tissue cell.