Pathogen-specific regulatory T cells provoke a shift in the Th1/Th2 paradigm in immunity to infectious diseases

Trends Immunol. 2002 Sep;23(9):450-5. doi: 10.1016/s1471-4906(02)02288-3.


Current dogma suggests that immunity to infection is controlled by distinct type 1 (Th1) and type 2 (Th2) subpopulations of T cells discriminated on the basis of cytokine secretion and function. However, a further subtype of T cells, with immunosuppressive function and cytokine profiles distinct from either Th1 or Th2 T cells, termed regulatory T (Tr) cells has been described. Although considered to have a role in the maintenance of self-tolerance, recent studies suggest that Tr cells can be induced against bacterial, viral and parasite antigens in vivo and might prevent infection-induced immunopathology or prolong pathogen persistence by suppressing protective Th1 responses. These observations have significant implications for our understanding of the role of T cells in immunity to infectious diseases and for the development of new therapies for immune-mediated disorders.

Publication types

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

MeSH terms

  • Animals
  • Cell Differentiation
  • Communicable Diseases / immunology*
  • Humans
  • Immune Tolerance
  • Interleukin-10 / immunology
  • Receptors, Antigen, T-Cell / immunology*
  • Th1 Cells / immunology*
  • Th1 Cells / metabolism
  • Th2 Cells / immunology*
  • Th2 Cells / metabolism
  • Transforming Growth Factor beta / immunology


  • Receptors, Antigen, T-Cell
  • Transforming Growth Factor beta
  • Interleukin-10