CD3 epsilon-mediated signals rescue the development of CD4+CD8+ thymocytes in RAG-2-/- mice in the absence of TCR beta chain expression

Int Immunol. 1994 Jul;6(7):995-1001. doi: 10.1093/intimm/6.7.995.


Recent studies have shown that TCR beta chain expression can effect the differentiation of CD4-CD8- double-negative (DN) thymocytes to CD4+CD8+ double-positive (DP) thymocytes. The TCR beta chain is expressed on the surface of DP thymocytes in association with CD3 gamma, delta and epsilon chains, suggesting a potential role for CD3 components in this signaling process. We now report detection of a very low level of surface expression of CD3 epsilon on adult DN RAG-2-/- thymocytes. This surface CD3 epsilon was associated with CD3 gamma and delta chains, as detected by anti-CD3 epsilon immunoprecipitation analyses. Significantly, injection of anti-CD3 epsilon mAb into RAG-2-/- mice led to the accumulation of an IL-2R alpha- CD2+ DP cell population and a nearly 100-fold increase in thymic cellularity to essentially normal levels. Together, these data strongly indicate that TCR beta chain-mediated developmental signals are transduced by CD3 components and provide potential insights into mechanisms by which TCR beta chain expression may effect this process.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antibodies, Monoclonal
  • CD3 Complex / immunology*
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • DNA-Binding Proteins*
  • Flow Cytometry
  • Mice
  • Mice, Mutant Strains
  • Proteins / immunology*
  • Receptors, Antigen, T-Cell, alpha-beta / immunology*
  • Signal Transduction / immunology*
  • Thymus Gland / cytology


  • Antibodies, Monoclonal
  • CD3 Complex
  • DNA-Binding Proteins
  • Proteins
  • Rag2 protein, mouse
  • Receptors, Antigen, T-Cell, alpha-beta
  • V(D)J recombination activating protein 2