Decidual and peripheral blood CD4+CD25+ regulatory T cells in early pregnancy subjects and spontaneous abortion cases.
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.
Department of Obstetrics and Gynecology, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama-shi, Toyama, 930-0194, Japan.
Y
Y
Sasaki
M
M
Sakai
S
S
Miyazaki
S
S
Higuma
A
A
Shiozaki
S
S
Saito
D000022:Abortion, Spontaneous / Q000276:immunology*; D017252:CD3 Complex / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D017635:Clonal Anergy; D003656:Decidua / Q000166:cytology*; D005260:Female; D006801:Humans; D011247:Pregnancy; D015375:Receptors, Interleukin-2 / Q000276:immunology*; D016176:T-Lymphocyte Subsets
D017252:CD3 Complex; D015375:Receptors, Interleukin-2