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.
Sasaki
Y
Y
Department of Obstetrics and Gynecology, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama-shi, Toyama, 930-0194, Japan.
Sakai
M
M
Miyazaki
S
S
Higuma
S
S
Shiozaki
A
A
Saito
S
S
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