• IL-10;
  • NK activity;
  • progesterone;
  • γ/δ subpopulations

PROBLEM: We have previously demonstrated a significantly increased ratio of γ/δ T-cell receptor (TCR)-positive progesterone receptor(PR)-positive cells in the peripheral blood of healthy pregnant women compared to that of recurrent aborters or non-pregnant individuals. Treatment of pregnancy lymphocytes with a pan anti-γ/δ TCR antibody inhibits progesterone-induced blocking factor (PIBF) production, increases natural killer (NK) activity, and alters the cytokine profile. The present study was aimed at investigating the role of the different γ/δ subpopulations in these phenomena.

METHOD OF STUDY: Peripherial blood lymphocytes from healthy pregnant women were incubated with either anti-γ1.4 and δ1, or anti-γ9 and δ2 antibodies. The effect of these treatments on PR induction and interleukin (IL)-10 and IL-12 expression were tested by immunocytochemistry. NK activity of anti-γ/δ treated lymphocytes was also determined.

RESULTS: In peripheral blood of healthy pregnant women, the most frequently occurring chain combination was γ1.4/δ1, whereas in recurrent aborters, the γ9/δ2 combination was predominant. Treatment of normal pregnancy lymphocytes with a mixture of γ1.4 and δ1 antibodies resulted in a significantly reduced NK activity and increased PR and IL-10 expression, whereas treatment with a mixture of γ9 and δ2 antibodies significantly reduced IL-10 production and slightly increased IL-12 production and NK activity. These data suggest the presence of two functionally distinct subpopulations in the peripheral blood of pregnant women.