γ/δT‐cell Subsets, NKG2A Expression and Apoptosis of Vδ2+ T cells in Pregnant Women with or without Risk of Premature Pregnancy Termination

PROBLEM: Potentially cytotoxic Vdelta2+ T lymphocytes recognize human leukocyte antigen-E on the trophoblast via their CD94/NKG2A receptors. This study aims at determing the percentage of gamma/delta T-cell subsets, their NKG2A and Annexin V positivity in peripheral blood of healthy pregnant women and women at risk of premature pregnancy termination. METHOD OF STUDY: Peripheral Vdelta2+ cells from healthy pregnant women and from women at risk of premature pregnancy termination were tested for the KIR NKG2A and Annexin V positivity by flow cytometry. RESULTS: The percentage of viable Vdelta2+ T cells was higher, that of Vdelta1+ T cells was lower in women at risk of premature pregnancy termination than in healthy pregnant women. The percentage of NKG2A + Vdelta2+ T cells was significantly lower in pregnant women at risk of premature pregnancy termination than in normal pregnancy. CONCLUSIONS: These data suggest the involvement of gamma/delta T lymphocytes in the pathogenesis of premature pregnancy termination.