Dominant IL-10 and TGF-β mRNA expression in γδT cells of human early pregnancy decidua suggests immunoregulatory potential

Abstract

Problem: To examine the cytokine gene expression in γδT-cells from human early pregnancy decidua. Method of study: The cytokine messenger RNA (mRNA) expression in isolated decidual T-cell receptor (TCR)γδ+/CD56+ and TCRγδ single positive cells was investigated with a panel of cytokine primers and probes selected to distinguish between T helper (Th)1, Th2, Th3 and regulatory T-cells (Tr1) type of immune response using real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Results: TCRγδ+/CD56+ cells express almost exclusively the immunosuppressive cytokines interleukin-10 (IL-10) and transforming growth factor (TGF)-β The TCRγδ single positive cells enhance their transcription of IL-10 and TGF-β, compared with the TCRγδ+/CD56+ cells and additionally express mRNA for IL-1β and IL-6. Conclusions: The present findings suggest that γδT cells in normal pregnancy create a cytokine milieu promoting immunotolerance to the fetus. We hypothesize that through the production of the immunosuppressive cytokines IL-10 and/or TGF-β the γδT cells could function directly as regulatory T cells or induce the differentiation of Th0 TCRαβ+ cells into regulatory/suppresser cells. © Blackwell Munksgaard, 2002.