In vivo activation of antigen-specific CD4 T cells.

Published

Journal Article (Review)

Physical detection of antigen-specific CD4 T cells has revealed features of the in vivo immune response that were not appreciated from in vitro studies. In vivo, antigen is initially presented to naïve CD4 T cells exclusively by dendritic cells within the T cell areas of secondary lymphoid tissues. Anatomic constraints make it likely that these dendritic cells acquire the antigen at the site where it enters the body. Inflammation enhances in vivo T cell activation by stimulating dendritic cells to migrate to the T cell areas and display stable peptide-MHC complexes and costimulatory ligands. Once stimulated by a dendritic cell, antigen-specific CD4 T cells produce IL-2 but proliferate in an IL-2--independent fashion. Inflammatory signals induce chemokine receptors on activated T cells that direct their migration into the B cell areas to interact with antigen-specific B cells. Most of the activated T cells then die within the lymphoid tissues. However, in the presence of inflammation, a population of memory T cells survives. This population is composed of two functional classes. One recirculates through nonlymphoid tissues and is capable of immediate effector lymphokine production. The other recirculates through lymph nodes and quickly acquires the capacity to produce effector lymphokines if stimulated. Therefore, antigenic stimulation in the presence of inflammation produces an increased number of specific T cells capable of producing effector lymphokines throughout the body.

Full Text

Cited Authors

  • Jenkins, MK; Khoruts, A; Ingulli, E; Mueller, DL; McSorley, SJ; Reinhardt, RL; Itano, A; Pape, KA

Published Date

  • 2001

Published In

Volume / Issue

  • 19 /

Start / End Page

  • 23 - 45

PubMed ID

  • 11244029

Pubmed Central ID

  • 11244029

International Standard Serial Number (ISSN)

  • 0732-0582

Digital Object Identifier (DOI)

  • 10.1146/annurev.immunol.19.1.23

Language

  • eng

Conference Location

  • United States