Unit

UNIT 17.3 MHC-Peptide Tetramers to Visualize Antigen-Specific T Cells

  1. John D. Altman1,
  2. Mark M. Davis2

Published Online: 1 MAY 2003

DOI: 10.1002/0471142735.im1703s53

Current Protocols in Immunology

Current Protocols in Immunology

How to Cite

Altman, J. D. and Davis, M. M. 2003. MHC-Peptide Tetramers to Visualize Antigen-Specific T Cells. Current Protocols in Immunology. 53:17.3:17.3.1–17.3.33.

Author Information

  1. 1

    Emory University School of Medicine, Atlanta, Georgia

  2. 2

    Stanford University School of Medicine and The Howard Hughes Medical Institute, Palo Alto, California

Publication History

  1. Published Online: 1 MAY 2003
  2. Published Print: FEB 2003

Abstract

Mature T lymphocytes of the CD8 or CD4 classes bear αβ T cell receptors (TCR) that are specific for a molecular complex consisting of a major histocompatibility complex class I or II (MHC class I or II) molecule bound to a unique self or foreign peptide. Until recently, methods for monitoring the T cell immune response to a viral or tumor antigen were restricted primarily to functional assays based on limiting dilution analysis, because the lack of specific molecular reagents to identify clonal T cells obviated approaches to identify and enumerate specific T cells. Development of efficient methods to express and refold MHC class I molecules with synthetic peptides coincided with identification of specific protein sequences that provide the substrate for enzymatic biotinylation. This combination has led to the development of a straightforward method for generating synthetic TCR ligands, making them tetravalent to provide increased avidity, and labeling them through a streptavidin moiety with useful fluorescent tags such as fluorescein or phycoerythrin. This unit describes the preparation of MHC class I/peptide tetramers in detail, including bacterial expression and refolding of the MHC class I light chain, β2-microglobulin (β2m), as well as the formation of a complex consisting of the MHC class I heavy chain of interest, β2m, and a chosen peptide.