Concerted antigen presentation by dendritic cells and B cells is necessary for optimal CD4 T-cell immunity in vivo

Immunology. 2005 Aug;115(4):556-64. doi: 10.1111/j.1365-2567.2005.02196.x.

Abstract

The relative contributions of different types of antigen presenting cells to T-cell activation, expansion and induction of effector functions are still not fully understood. In order to evaluate the roles of dendritic versus B cells during these phases of a CD4 T-cell response in vivo, we adoptively transferred major histocompatibility complex class II restricted, T-cell receptor-transgenic CD4+ T cells into transgenic mice expressing selectively the T-cell restricting class II molecules on either dendritic cells, B cells or both. Upon immunization with peptide antigen, we observed that dendritic cells were sufficient to induce activation, expansion, interleukin-2 production and germinal centre migration of antigen-specific T cells, independently of other antigen-presenting cells. In contrast, neither resting nor activated B cells had similar antigen-presenting capacities in vivo. However, in double transgenic mice where both B cells and dendritic cells were capable of presenting antigen, T cells showed increased proliferation, expansion and cytokine production in vivo. Moreover, higher antigen-specific CD4 T-cell numbers accumulated in germinal centres. Our data demonstrate that dendritic cells are sufficient to activate naive CD4 T cells in vivo, but B cells subsequently can enhance CD4 T-cell expansion further.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adoptive Transfer / methods
  • Animals
  • Antigen Presentation / immunology*
  • Antigen-Presenting Cells / immunology
  • Antigens, CD / immunology
  • B-Lymphocytes / immunology*
  • CD4 Antigens / immunology
  • CD4-Positive T-Lymphocytes / immunology*
  • Cell Division / immunology
  • Cell Size
  • Dendritic Cells / immunology*
  • Histocompatibility Antigens Class II / immunology
  • Immunity, Cellular / immunology
  • Interleukin-2 / immunology
  • Lymphocyte Activation / immunology
  • Mice
  • Mice, Transgenic
  • Receptors, Antigen, T-Cell / immunology

Substances

  • Antigens, CD
  • CD4 Antigens
  • Histocompatibility Antigens Class II
  • Interleukin-2
  • Receptors, Antigen, T-Cell