γδTCR⁺ cells of the pregnant ovine uterus express variable T cell receptors and contain granulysin

Abstract 

γδ T cells are a prominent granulated cell population in the ruminant pregnant uterus and both their number and granule size increase dramatically during pregnancy. Anchor-RT-PCR was used to assess TCRδ gene usage by γδ T cells from the uterine epithelium of pregnant sheep. The TCRδ genes obtained exhibited distinct combinatorial and junctional diversity and only two out of nine V–D–J rearrangements sequenced were identical. Furthermore, two of the Vδ elements used are also expressed in peripheral blood, indicating that γδTCR use in sheep epithelia is neither restricted nor site-specific, similar to humans but in contrast to findings in mice. Protein analysis of purified, granulated uterine γδ T cells revealed the presence of large amounts of the antimicrobial peptide, granulysin. The results of the present study indicate that ovine uterine γδTCR⁺ intraepithelial lymphocytes have the potential to recognise diverse antigens and may have a role in protecting the uterus from infection during pregnancy and parturition. A similar protective role for γδ T cells may exist in the human decidua parietalis.

Keywords: Intraepithelial lymphocytes, γδ T cells, Granulysin, Pregnancy, Uterus, Sheep