Polarized Th2 cytokine expression by both mucosal γδ and αβ T cells

Academic Article

Abstract

  • Currently only limited information is available as to why dominant IgA isotype responses are supported by mucosal T cells in effector tissues. To address this issue directly, γδ and αβ T cells were isolated from the submandibular gland (SMG) of mice as an example of mucosal effector tissues. Freshly isolated CD3+ T cells from this tissue contained relatively high numbers of activated cells [approximately 10% interleukin‐2 receptor (IL‐2R)+ cells and 15% of cells in cycle stages S and G2 + M], of which 25% and 75% were γδ and αβ T cells, respectively. The cytokine‐specific quantitative reverse transcriptase‐polymerase chain reaction and enzyme‐linked immunospot analyses revealed that, although both γδ and αβ T cells were capable of producing an array of Th1 or Th2 cytokines following stimulation via the T cell receptor‐CD3 complex, these mucosal T cells were mainly committed to IL‐5 and IL‐6 expression in vivo (Th2 type). Both freshly isolated γδ and αβ T cells expressed mRNA and contained IL‐5 and IL‐6 spot‐forming cells (SFC); however, only the latter exhibited high mRNA levels and SFC for a Th1 cytokine (interferon‐γ). Taken together, the results show that freshly isolated CD3+ T cells from SMG contain activated γδ and αβ T cells which are programmed to produce IL‐5 and IL‐6. Thus, SMG, an example of an IgA effector tissue, can be characterized as a Th2‐dominant site. However, although both γδ and αβ T cells express cytokine profiles consistent with a Th2 phenotype, only the latter subset with a CD4+CD8− phenotype provided effective help for mucosal B cell responses in vitro. Copyright © 1995 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
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    Digital Object Identifier (doi)

    Author List

  • Hiroi T; Fujihashi K; McGhee JR; Kiyono H
  • Start Page

  • 2743
  • End Page

  • 2751
  • Volume

  • 25
  • Issue

  • 10