Immunologic Research

, Volume 27, Issue 2, pp 277–286

Ligand-dependent regulation of T cell development and activation

  • Ronald N. Germain

DOI: 10.1385/IR:27:2-3:277

Cite this article as:
Germain, R.N. Immunol Res (2003) 27: 277. doi:10.1385/IR:27:2-3:277


Mature CD4+ and CD8+T lymphocytes develop in the thymus from precursors with diverse clonally distributed receptors, possessing binding sites with negligible, intermediate, or high affinity for self-peptide: major histocompatibility complex (MHC) ligands. Positive-and negative-selection processes acting on this precursor pool yield a peripheral T cell population comprised of cells with receptors (TCR) capable of self-peptide: MHC ligand recognition, but largely depleted of those able to mediate overt self-responsiveness. The Lymphocyte Biology Section of the Laboratory of Immunology studies how self-ligand recognition guides T cell development in the thymus and influences the functionality of naive and activated T cells in the periphery. It also seeks to define the molecular basis for the discrimination between self-ligands and foreign antigens that controls T cell activation to effector function. Finally, it uses a combination of conventional cellular immunological methods, biochemical and biophysical studies, and advanced imaging techniques to visualize, quantitate, and model the various steps in the development of primary and memory T cell immune responses.

Key Words

T lymphocyteT cell receptorMHC moleculeAntigenThymusCD4CD8SignalingVaccinesAutoimmunityTolerance

Copyright information

© Humana Press Inc. 2003

Authors and Affiliations

  • Ronald N. Germain
    • 1
  1. 1.Lymphocyte Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesda