Visualization of naturally occurring Foxp3+ regulatory T cells in normal and tumor-bearing mice

Int Immunopharmacol. 2004 Dec 20;4(14):1785-93. doi: 10.1016/j.intimp.2004.07.026.


CD25+CD4+ regulatory T cells (Treg) play pivotal roles in the host response to tumors. However, their exact location in vivo is largely unknown. The forkhead/winged helix transcription factor, Foxp3, is specifically expressed in naturally occurring Treg (nTreg) and programs their development and function. In this study, we produced a rabbit polyclonal antibody (pAb), which can detect mouse Foxp3 protein in situ. Results using this pAb revealed that Foxp3+CD4+ nTreg cells occur in direct contact with CD11c+ dendritic cells (DCs), and Foxp3-CD4+ and CD8+T lymphocytes in the T cell regions of lymphoid tissues from normal and tumor-bearing mice. The numbers of Foxp3+CD4+ nTreg cells are significantly increased in draining, but not nondraining, lymph nodes (LNs) and spleen (SPL) of tumor-bearing mice. Furthermore, a small number of nTreg could be also found at the tumor site. These observations support the notion that the numbers of Foxp3+CD4+ nTreg are increased by tumors and may contribute to the immunosuppression observed in tumor-bearing hosts at secondary lymphoid organs and also possibly at the tumor site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / pharmacology
  • CD4-Positive T-Lymphocytes / metabolism
  • Cell Separation
  • DNA-Binding Proteins / genetics*
  • Female
  • Forkhead Transcription Factors
  • Immunohistochemistry
  • Indicators and Reagents
  • Lymph Nodes / cytology
  • Lymphocyte Count
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Neoplasms, Experimental / metabolism
  • Neoplasms, Experimental / pathology
  • Receptors, Interleukin-2 / metabolism
  • T-Lymphocytes / metabolism*


  • Antibodies, Monoclonal
  • DNA-Binding Proteins
  • Forkhead Transcription Factors
  • Foxp3 protein, mouse
  • Indicators and Reagents
  • Receptors, Interleukin-2