UNIT 10.31 Measurement of Mouse T Cell Receptor Excision Circles

  1. Gregory D. Sempowski,
  2. Maria E. Rhein

Published Online: 1 NOV 2004

DOI: 10.1002/0471142735.im1031s63

Current Protocols in Immunology

Current Protocols in Immunology

How to Cite

Sempowski, G. D. and Rhein, M. E. 2004. Measurement of Mouse T Cell Receptor Excision Circles. Current Protocols in Immunology. 63:VII:10.31:10.31.1–10.31.12.

Author Information

  1. Duke University, Durham, North Carolina

Publication History

  1. Published Online: 1 NOV 2004
  2. Published Print: OCT 2004


This unit provides the protocols necessary for the quantification of mouse single joint T cell receptor excision circles (sjTRECs) generated during TCRA gene rearrangement. These nonreplicated episomal circles of DNA are generated by the recombination process used to produce antigen-specific T cell receptors. The number of sjTRECs per mg of thymus tissue or per 100,000 lysed cells has been shown to be a molecular marker of thymopoiesis and naïve T cells. This technology is beneficial to investigators interested in quantitating the level of thymopoiesis occurring in both in vivo and in vitro mouse systems and complements traditional phenotypic analyses of thymopoiesis. The Basic Protocol for real-time PCR details the assay for use on a Bio-Rad iCycler iQ. An Alternate Protocol is provided for an ABI Prism 7700. In addition, the unit includes Support Protocols for preparation of a mouse sjTREC DNA standard (Support Protocol 1) and preparation of mouse thymus tissue DNA (Support Protocol 2) as well as a protocol for proteinase K lysis of lymphocytes (Support Protocol 3) used in the Basic and Alternate protocols.


  • Mouse;
  • Thymopoiesis;
  • T cell receptor;
  • Real-time PCR