Molecular biology and immunology for clinicians 17: T-cell signal transduction

Leonard H Sigal1

  • 1Division of Rheumatology and Connective Tissue Research, Department of Medicine,University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick, NJ 08903-0019, USA. sigallh@umdnj.edu

Peptide antigen recognition by T-cells occurs because of the interaction of the epitope cradled within the peptide-binding groove of the major histocompatibility complex molecule on the surface of an antigen-presenting cell with the T-cell antigen receptor, a heterodimer whose chains belong to the immunoglobulin superfamily. Passage of the message from the receptor to the cell's nucleus occurs via a complex choreography of kinases, calcium, and chemical combinations consisting of families of proteins described by arcane acronyms, numbers and letters that perplex the casual observer. However, taming the T-cell is crucial in transplantation and in controlling autoimmunity. Behind the jargon is a fascinating, albeit confusing, set of mechanisms that already offer therapeutic promise.

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