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Examination of Thymic Positive and Negative Selection by Flow Cytometry
14:29

Examination of Thymic Positive and Negative Selection by Flow Cytometry

Published on: October 8, 2012

Positive and negative selection of T cells

Timothy K Starr1, Stephen C Jameson, Kristin A Hogquist

  • 1Center for Immunology and the Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55455, USA. star0044@umn.edu

Annual Review of Immunology
|November 5, 2002
PubMed

A functional immune system requires the selection of T lymphocytes expressing receptors that are major histocompatibility complex restricted but tolerant to self-antigens. This selection occurs predominantly in the thymus, where lymphocyte precursors first assemble a surface receptor. In this review we summarize the current state of the field regarding the natural ligands and molecular factors required for positive and negative selection and discuss a model for how these disparate outcomes can be signaled via the same receptor. We also discuss emerging data on the selection of regulatory T cells. Such cells require a high-affinity interaction with self-antigens, yet differentiate into regulatory cells instead of being eliminated.

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