Long-lived central memory γδ T cells confer protection against murine cytomegalovirus reinfection.

The involvement of γδ TCR-bearing lymphocytes in immunological memory has gained increasing interest due to their functional duality between adaptive and innate immunity. γδ T effector memory (TEM) and central memory (TCM) subsets have been identified, but their respective roles in memory responses are poorly understood. In the present study, we used subsequent mouse cytomegalovirus (MCMV) infections of αβ T cell deficient mice in order to analyze the memory potential of γδ T cells.

Sensing of cell stress by human γδ TCR-dependent recognition of annexin A2.

Human γδ T cells comprise a first line of defense through T-cell receptor (TCR) recognition of stressed cells. However, the molecular determinants and stress pathways involved in this recognition are largely unknown. Here we show that exposure of tumor cells to various stress situations led to tumor cell recognition by a Vγ8Vδ3 TCR.

γδ T cells confer protection against murine cytomegalovirus (MCMV).

Cytomegalovirus (CMV) is a leading infectious cause of morbidity in immune-compromised patients. γδ T cells have been involved in the response to CMV but their role in protection has not been firmly established and their dependency on other lymphocytes has not been addressed. Using C57BL/6 αβ and/or γδ T cell-deficient mice, we here show that γδ T cells are as competent as αβ T cells to protect mice from CMV-induced death.

Anti-metastatic potential of human Vδ1(+) γδ T cells in an orthotopic mouse xenograft model of colon carcinoma.

The role of human intraepithelial Vδ1(+) γδ T cell cytotoxic effectors in the immune surveillance against metastatic colon cancer has never been addressed, despite their reported capacity to infiltrate colon carcinomas and to kill colonic cancer cells in vitro. We previously showed that Vδ1(+) γδ T cells are enriched in blood in response to cytomegalovirus (CMV) infection, and that such increase may be protective against epithelial cancers. The objective of the present study was to investigate whether CMV-induced Vδ1(+) γδ T lymphocytes could inhibit the propagation of human colon tumors in vivo, in order to evaluate their immunotherapeutic potential in this context.

Cytomegalovirus and tumor stress surveillance by binding of a human γδ T cell antigen receptor to endothelial protein C receptor.

T cells bearing γδ T cell antigen receptors (TCRs) function in lymphoid stress surveillance. However, the contribution of γδ TCRs to such responses is unclear. Here we found that the TCR of a human V(γ)4V(δ)5 clone directly bound endothelial protein C receptor (EPCR), which allowed γδ T cells to recognize both endothelial cells targeted by cytomegalovirus and epithelial tumors.

Key implication of CD277/butyrophilin-3 (BTN3A) in cellular stress sensing by a major human γδ T-cell subset.

Human peripheral Vγ9Vδ2 T cells are activated by phosphorylated metabolites (phosphoagonists [PAg]) of the mammalian mevalonate or the microbial desoxyxylulose-phosphate pathways accumulated by infected or metabolically distressed cells. The underlying mechanisms are unknown. We show that treatment of nonsusceptible target cells with antibody 20.

Up-regulation of cytolytic functions of human Vδ2-γ T lymphocytes through engagement of ILT2 expressed by tumor target cells.

In humans, the majority of peripheral blood γδ T cells expresses Vγ9Vδ2 T-cell receptors (TCR) and recognize nonpeptidic phosphorylated antigens. In contrast, most tissue-derived γδ T cells, which are located mainly in spleen and epithelia, preferentially use Vδ1 or Vδ3 chains paired with diverse Vγ chains to form their TCR. Our knowledge about the antigenic specificity and costimulation requirements of human Vδ2(-) γδ T cells remains limited.

Common features of gammadelta T cells and CD8(+) alphabeta T cells responding to human cytomegalovirus infection in kidney transplant recipients.

Background: Kidney transplant recipients infected with cytomegalovirus (CMV) undergo a persistent gammadelta T cell expansion in their peripheral blood. The anti-CMV function of these cells was previously demonstrated by their ability to kill CMV-infected cells in vitro.

Methods: To gain insight into the role of gammadelta T cells within the antiviral immune network, we compared the expansion kinetics of these T cells with that of CMV pp65-specific CD8(+) alphabeta T cells in the peripheral blood of twenty-one kidney transplant recipients.

Ectopic expression of the ets transcription factor ER81 in transgenic mouse mammary gland enhances both urokinase plasminogen activator and stromelysin-1 transcription.

The PEA3 group members PEA3, ER81 and ERM, which are highly conserved transcription factors from the Ets family, are over-expressed in metastatic mammary tumors. In the current study, we present the characterization of a transgenic mouse strain which over-expresses ER81 in the mammary gland via the long terminal repeat of the mouse mammary tumor virus (LTR-MMTV). Although six genotypically positive transgenic lines were identified, only one expressed the ectopic transcript with an exclusive expression in the lactating and late-pregnancy (18th day) mammary glands.