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Glauner, T.

Publications and source records attributed to Glauner, T..

2 recordsLinked to original sources

NKG2D signaling regulates IL-17A-producing γδT cells to promote cancer progression

{gamma}{delta}T cells are unconventional T cells particularly abundant in mucosal tissues that play an important role in tissue surveillance and homeostasis. {gamma}{delta}T cell activation is mediated by the T cell receptor composed of {gamma} and {delta} chains, as well as activating receptors for stress-induced ligands, such as NKG2D. Contrary to the well-established anti-tumor function of {gamma}{delta}T cells, recent studies have shown that {gamma}{delta}T cells can promote tumor development in certain contexts. However, the mechanisms leading to this diseasepromoting role remain poorly understood. Here, we show that mice lacking {gamma}{delta}T cells survive longer in a mouse model of intestinal cancer, further supporting their pro-tumoral role. In a surprising conceptual twist, we found that these pro-tumor {gamma}{delta}T cells are regulated by NKG2D signaling, a receptor normally associated with cancer cell killing. Germline deletion of Klrk1, the gene encoding NKG2D, reduced the frequency of {gamma}{delta}T cells in the tumor microenvironment and delayed tumor progression. We further show that blocking NKG2D reduces the capability of {gamma}{delta}T cells to produce IL-17A in the pre-metastatic lung and that co-culture of lung T cells with NKG2D ligand-expressing tumor cells specifically increases the frequency of {gamma}{delta}T cells. Together, these data support the hypothesis that in a tumor microenvironment where NKG2D ligands are constitutively expressed, {gamma}{delta}T cells accumulate in an NKG2D-dependent manner and drive tumor progression by secreting pro-inflammatory cytokines, such as IL-17A.

immunology

Single-cell analysis uncovers differential regulation of lung γδ T cell subsets by the co-inhibitory molecules, PD-1 and TIM-3

IL-17A-producing {gamma}{delta} T cells within the lung consist of both V{gamma}6+ tissue-resident cells and V{gamma}4+ circulating cells that play important roles in homeostasis, inflammation, infection, tumor progression and metastasis. How these {gamma}{delta} T cell subsets are regulated in the lung environment during homeostasis and cancer remains poorly understood. Using single-cell RNA sequencing and flow cytometry, we show that lung V{gamma}6+ cells express a repertoire of cell surface molecules distinctive from V{gamma}4+ cells, including PD-1 and ICOS. We found that PD-1 functions as a co-inhibitory molecule on V{gamma}6+ cells to reduce IL-17A production, whereas manipulation of ICOS signaling fails to affect IL-17A in V{gamma}6+ cells. In a mammary tumor model, ICOS and PD-1 expression on lung V{gamma}6+ cells remained stable. However, V{gamma}6+ and V{gamma}4+ cells within the lung pre-metastatic niche increased expression of IL-17A, IL-17F, amphiregulin (AREG) and TIM-3 in response to tumor-derived IL-1{beta} and IL-23, where the upregulation of TIM-3 was specific to V{gamma}4+ cells. Inhibition of either PD-1 or TIM-3 in mammary tumor-bearing mice further increased IL-17A by V{gamma}6+ and V{gamma}4+ cells, indicating that both PD-1 and TIM-3 function as negative regulators of IL-17A-producing {gamma}{delta} T cell subsets. Together, these data demonstrate how lung {gamma}{delta} T cell subsets are differentially controlled by co-inhibitory molecules in steady-state and cancer.

immunology