Abstract :
Byline: Jennifer E. Smith-Garvin, Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: smithje@mail.med.upenn.edu; Gary A. Koretzky, Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: smithje@mail.med.upenn.edu, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: koretzky@mail.med.upenn.edu, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: jordanm@mail.med.upenn.edu; Martha S. Jordan, Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: smithje@mail.med.upenn.edu, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104; email: koretzky@mail.med.upenn.edu Keywords: signal transduction, immunoreceptor, integrin Abstract This year marks the 25th anniversary of the first Annual Review of Immunology article to describe features of the T cell antigen receptor (TCR). In celebration of this anniversary, we begin with a brief introduction outlining the chronology of the earliest studies that established the basic paradigm for how the engaged TCR transduces its signals. This review continues with a description of the current state of our understanding of TCR signaling, as well as a summary of recent findings examining other key aspects of T cell activation, including cross talk between the TCR and integrins, the role of costimulatory molecules, and how signals may negatively regulate T cell function.