TCRγδ cells and viruses

T-cell receptor ya cells (TCR gamma delta) are often found in increased numbers during the course of several viral infections in humans. Although these findings suggest an important role for th is unique subset, their precise function has not been ascertained. Recent studies in murine models of both RNA and DNA virus infections have begun to shed new light on the potential function for TCR gamma delta cells in antiviral immunity. It is clear that TCR gamma delta cells participate in the immune response to human immunodeficiency virus (HIV), influenza, Sendai, coxsackie, vaccinia, vesicular stomatitis virus (VSV), and herpes simplex virus-1 (HSV-1) viral infections since they become activated and home to the sites of viral replication. In this review we will summarize current efforts to dissect the role of TCR gamma delta eel Is in these disease settings, emphasizing the effector functions utilized, the TCR repertoire, and the antigens recognized. Particular focus will be placed on HSV-1 infections where we have begun to address these issues and have shown that TCR gamma delta cells are sufficient for protection from lethal infection and are able to recognize the herpes virus antigen glycoprotein I.