Decidual and peripheral blood CD4+CD25+ regulatory T cells in early pregnancy subjects and spontaneous abortion cases

Mol Hum Reprod. 2004 May;10(5):347-53. doi: 10.1093/molehr/gah044. Epub 2004 Mar 2.

Abstract

Human pregnancy represents a situation of semiallograft to maternal host. Therefore, it has been reported that tolerance to the fetal allograft represents a mechanism for maintaining a pregnancy. CD4(+)CD25(bright) regulatory T cells are known to play an important role in the development and maintenance of tolerance in peripheral tissues. However, the potential role of CD4(+)CD25(bright) T cells in maintaining human pregnancy has not been reported. In this study, we show that early human pregnancy decidua contains an abundance of CD4(+)CD25(bright) T cells, which express CD152(CTLA-4) at a high level. CD4(+)CD25(bright) T cells mediate potent inhibition of autologous T-cell proliferation by anti-CD3 stimulation. Furthermore, these cells inhibit the proliferation of autologous CD4(+)CD25(-) T cells in a dose-dependent fashion. This suppressive function of decidual CD4(+)CD25(+) T cells required cell-to-cell contact. The proportion of decidual CD4(+)CD25(bright) T cells was significantly lower in specimens from spontaneous abortion compared to those from specimens from induced abortions. These results suggest that decidual CD4(+)CD25(bright) T cells contribute to the mechanisms mediating maternal immune tolerance of conceptus antigens and therefore might contribute to the maintenance of pregnancy.

MeSH terms

  • Abortion, Spontaneous / immunology*
  • CD3 Complex / immunology
  • CD4-Positive T-Lymphocytes / immunology*
  • Clonal Anergy
  • Decidua / cytology*
  • Female
  • Humans
  • Pregnancy
  • Receptors, Interleukin-2 / immunology*
  • T-Lymphocyte Subsets

Substances

  • CD3 Complex
  • Receptors, Interleukin-2