A spatial view of the CD8+ T-cell response: the case of HCV

In viral infections, a memory T-cell population comprises multiple subtypes of cells, distributed in diverse anatomic compartments and possibly re-circulating among them. Accordingly, memory T cells display distinct phenotypes and functions, depending on the nature of the infecting virus, the anatomic location of the infection, and the differences between the sites of active infection and T-cell collection. This paper explores the body compartments where virus-specific CD8(+) T cells have been found during chronic hepatitis C virus infection, describes the cells' memory qualities, and discusses how they are spatially regulated, in comparison with other human viral infections. Understanding the role of compartmentalization and diversity of HCV-specific memory T-cell subsets may be the key to developing effective immunotherapies.