Hepatic effector CD8(+) T-cell dynamics.

CD8(+) T cells play a critical role in hepatitis B virus (HBV) pathogenesis. During acute, self-limited infections, these cells are instrumental to viral clearance; in chronic settings, they sustain repetitive cycles of hepatocellular necrosis that promote hepatocellular carcinoma development. Both CD8(+) T-cell defensive and destructive functions are mediated by antigen-experienced effector cells and depend on the ability of these cells to migrate to the liver, recognize hepatocellular antigens and perform effector functions. Understanding the signals that modulate the spatiotemporal dynamics of CD8(+) T cells in the liver, particularly in the context of antigen recognition, is therefore critical to gaining insight into the pathogenesis of acute and chronic HBV infection. Here, we highlight recent data on how effector CD8(+) T cells traffic within the liver, and we discuss the potential for novel imaging techniques to shed light on this important aspect of HBV pathogenesis.