Phenotypic Heterogeneity of Antigen-Specific CD4 T Cells Under Different Conditions of Antigen Persistence and Antigen Load

Eur J Immunol. 2004 Dec;34(12):3525-33. doi: 10.1002/eji.200425324.

Abstract

The factors responsible for the phenotypic heterogeneity of memory CD4 T cells are unclear. In the present study, we have identified a third population of memory CD4 T cells characterized as CD45RA(+)CCR7(-) that, based on its replication history and the homeostatic proliferative capacity, was at an advanced stage of differentiation. Three different phenotypic patterns of memory CD4 T cell responses were delineated under different conditions of antigen (Ag) persistence and load using CD45RA and CCR7 as markers of memory T cells. Mono-phenotypic CD45RA(-)CCR7(+) or CD45RA(-)CCR7(-) CD4 T cell responses were associated with conditions of Ag clearance (tetanus toxoid-specific CD4 T cell response) or Ag persistence and high load (chronic HIV-1 and primary CMV infections), respectively. Multi-phenotypic CD45RA(-)CCR7(+), CD45RA(-)CCR7(-) and CD45RA(+)CCR7(-) CD4 T cell responses were associated with protracted Ag exposure and low load (chronic CMV, EBV and HSV infections and HIV-1 infection in long-term nonprogressors). The mono-phenotypic CD45RA(-)CCR7(+) response was typical of central memory (T(CM)) IL-2-secreting CD4 T cells, the mono-phenotypic CD45RA(-)CCR7(-) response of effector memory (T(EM)) IFN-gamma-secreting CD4 T cells and the multi-phenotypic response of both IL-2- and IFN-gamma-secreting cells. The present results indicate that the heterogeneity of different Ag-specific CD4 T cell responses is regulated by Ag exposure and Ag load.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens / immunology*
  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / immunology*
  • Cell Division / immunology
  • Cytomegalovirus Infections / immunology
  • HIV Infections / immunology
  • Humans
  • Immunologic Memory / immunology*

Substances

  • Antigens