Virus receptors in the human central nervous system

The initial event in the life cycle of a virus is its interaction with rece ptors present on the surface of a cell. Understanding these interactions is important to our understanding of viral tropism, spread, and pathogenesis. This is particularly true of viruses that target the central nervous syste m as these viruses must maintain a tropism for both the nervous system and for peripheral organs that allow for viral replication and spread to new su sceptible hosts. These viruses therefore interact with a diverse set of cel ls and tissues, interactions that are likely mediated by both common and un ique receptors present an each target tissue. In addition, physiological ch anges in the host can lead to increased or decreased expression of virus re ceptors, which influence virus trafficking, spread, and tissue specific pat hology This review will focus on the relatively few virus receptor systems that have been described in some level of detail for viruses that target th e human central nervous system.