Elena Tomasello

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Natural killer (NK) cells are effector lymphocytes of the innate immune system that control several types of tumors and microbial infections by limiting their spread and subsequent tissue damage. Recent research highlights the fact that NK cells are also regulatory cells engaged in reciprocal interactions with dendritic cells, macrophages, T cells and(More)
NKp46+CD3- natural killer lymphocytes isolated from blood, lymphoid organs, lung, liver and uterus can produce granule-dependent cytotoxicity and interferon-gamma. Here we identify in dermis, gut lamina propria and cryptopatches distinct populations of NKp46+CD3- cells with a diminished capacity to degranulate and produce interferon-gamma. In the gut,(More)
Optimal lymphocyte activation requires the simultaneous engagement of stimulatory and costimulatory receptors. Stimulatory immunoreceptors are usually composed of a ligand-binding transmembrane protein and noncovalently associated signal-transducing subunits. Here, we report that alternative splicing leads to two distinct NKG2D polypeptides that associate(More)
Several proteins are expressed in both immune and nervous systems. However, their putative nonimmune functions in the brain remain poorly understood. KARAP/DAP12 is a transmembrane polypeptide associated with cell-surface receptors in hematopoeitic cells. Its mutation in humans induces Nasu-Hakola disease, characterized by presenile dementia and(More)
The interferon (IFN)-gamma-induced TRAIL effector mechanism is a vital component of cancer immunosurveillance by natural killer (NK) cells in mice. Here we show that the main source of IFN-gamma is not the conventional NK cell but a subset of B220(+)Ly6C(-) dendritic cells, which are atypical insofar as they express NK cell-surface molecules. Upon contact(More)
Consistent with their function in immune surveillance, natural killer (NK) cells are distributed throughout lymphoid and nonlymphoid tissues. However, the mechanisms governing the steady-state trafficking of NK cells remain unknown. The lysophospholipid sphingosine 1-phosphate (S1P), by binding to its receptor S1P1, regulates the recirculation of T and B(More)
The gut is a major barrier against microbes and encloses various innate lymphoid cells (ILCs), including two subsets expressing the natural cytotoxicity receptor NKp46. A subset of NKp46(+) cells expresses retinoic acid receptor-related orphan receptor γt (RORγt) and produces IL-22, like lymphoid tissue inducer (LTi) cells. Other NKp46(+) cells lack RORγt(More)
Natural killer (NK) cells are large granular lymphocytes of the innate immune system that participate in the early control of microbial infections and cancer. NK cells can induce the death of autologous cells undergoing various forms of stress, recognizing and providing non-microbial 'danger' signals to the immune system. NK cells are widely distributed in(More)
NKp46 is a cell surface receptor expressed on natural killer (NK) cells, on a minute subset of T cells, and on a population of innate lymphoid cells that produce IL-22 and express the transcription factor retinoid-related orphan receptor (ROR)-γt, referred to as NK cell receptor (NKR)(+)ROR-γt(+) cells. Here we describe Nkp46(iCre) knock-in mice in which(More)
Natural killer cell and T cell subsets express at their cell surface a repertoire of receptors for MHC class I molecules, the natural killer cell receptors (NKRs). NKRs are characterized by the existence of inhibitory and activating isoforms, which are encoded by highly homologous but separate genes present in the same locus. Inhibitory isoforms express an(More)