| 1. |
- Bryceson, YT, et al.
(författare)
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Cytolytic granule polarization and degranulation controlled by different receptors in resting NK cells
- 2005
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 202:7, s. 1001-1012
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Tidskriftsartikel (refereegranskat)abstract
- The relative contribution to cytotoxicity of each of the multiple NK cell activation receptors has been difficult to assess. Using Drosophila insect cells, which express ligands of human NK cell receptors, we show that target cell lysis by resting NK cells is controlled by different receptor signals for cytolytic granule polarization and degranulation. Intercellular adhesion molecule (ICAM)-1 on insect cells was sufficient to induce polarization of granules, but not degranulation, in resting NK cells. Conversely, engagement of the Fc receptor CD16 by rabbit IgG on insect cells induced degranulation without specific polarization. Lysis by resting NK cells occurred when polarization and degranulation were induced by the combined presence of ICAM-1 and IgG on insect cells. Engagement of receptor 2B4 by CD48 on insect cells induced weak polarization and no degranulation. However, coengagement of 2B4 and CD16 by their respective ligands resulted in granule polarization and cytotoxicity in the absence of leukocyte functional antigen-1–mediated adhesion to target cells. These data show that cytotoxicity by resting NK cells is controlled tightly by separate or cooperative signals from different receptors for granule polarization and degranulation.
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| 2. |
- Campbell, TM, et al.
(författare)
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IL2RB maintains immune harmony
- 2019
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 216:6, s. 1231-1233
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Tidskriftsartikel (refereegranskat)abstract
- How the IL-2 receptor β-chain specifically shapes immunity has remained enigmatic. In this issue of JEM, Zhang et al. (https://doi.org/10.1084/jem.20182304) and Fernandez et al. (https://doi.org/10.1084/jem.20182015) independently report the first observations of autosomal recessive mutations in IL2RB, revealing a requirement for IL2RB in immunity and peripheral immune tolerance.
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| 3. |
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| 4. |
- Campbell, TM, et al.
(författare)
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Respiratory viral infections in otherwise healthy humans with inherited IRF7 deficiency
- 2022
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 219:7
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Tidskriftsartikel (refereegranskat)abstract
- Autosomal recessive IRF7 deficiency was previously reported in three patients with single critical influenza or COVID-19 pneumonia episodes. The patients’ fibroblasts and plasmacytoid dendritic cells produced no detectable type I and III IFNs, except IFN-β. Having discovered four new patients, we describe the genetic, immunological, and clinical features of seven IRF7-deficient patients from six families and five ancestries. Five were homozygous and two were compound heterozygous for IRF7 variants. Patients typically had one episode of pulmonary viral disease. Age at onset was surprisingly broad, from 6 mo to 50 yr (mean age 29 yr). The respiratory viruses implicated included SARS-CoV-2, influenza virus, respiratory syncytial virus, and adenovirus. Serological analyses indicated previous infections with many common viruses. Cellular analyses revealed strong antiviral immunity and expanded populations of influenza- and SARS-CoV-2–specific memory CD4+ and CD8+ T cells. IRF7-deficient individuals are prone to viral infections of the respiratory tract but are otherwise healthy, potentially due to residual IFN-β and compensatory adaptive immunity.
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| 5. |
- Cichocki, F, et al.
(författare)
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ARID5B regulates metabolic programming in human adaptive NK cells
- 2018
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 215:9, s. 2379-2395
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Tidskriftsartikel (refereegranskat)abstract
- Natural killer (NK) cells with adaptive immunological properties expand and persist in response to human cytomegalovirus. Here, we explored the metabolic processes unique to these cells. Adaptive CD3−CD56dimCD57+NKG2C+ NK cells exhibited metabolic hallmarks of lymphocyte memory, including increased oxidative mitochondrial respiration, mitochondrial membrane potential, and spare respiratory capacity. Mechanistically, we found that a short isoform of the chromatin-modifying transcriptional regulator, AT-rich interaction domain 5B (ARID5B), was selectively induced through DNA hypomethylation in adaptive NK cells. Knockdown and overexpression studies demonstrated that ARID5B played a direct role in promoting mitochondrial membrane potential, expression of genes encoding electron transport chain components, oxidative metabolism, survival, and IFN-γ production. Collectively, our data demonstrate that ARID5B is a key regulator of metabolism in human adaptive NK cells, which, if targeted, may be of therapeutic value.
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| 6. |
- Cichocki, F, et al.
(författare)
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Transcriptional regulation of Munc13-4 expression in cytotoxic lymphocytes is disrupted by an intronic mutation associated with a primary immunodeficiency
- 2014
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 211:6, s. 1079-1091
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Tidskriftsartikel (refereegranskat)abstract
- Autosomal recessive mutations in UNC13D, the gene that encodes Munc13-4, are associated with familial hemophagocytic lymphohistiocytosis type 3 (FHL3). Munc13-4 expression is obligatory for exocytosis of lytic granules, facilitating cytotoxicity by T cells and natural killer (NK) cells. The mechanisms regulating Munc13-4 expression are unknown. Here, we report that Munc13-4 is highly expressed in differentiated human NK cells and effector CD8+ T lymphocytes. A UNC13D c.118-308C>T mutation, causative of FHL3, disrupted binding of the ETS family member ELF1 to a conserved intronic sequence. This mutation impairs UNC13D intron 1 recruitment of STAT4 and the chromatin remodeling complex component BRG1, diminishing active histone modifications at the locus. The intronic sequence acted as an overall enhancer of Munc13-4 expression in cytotoxic lymphocytes in addition to representing an alternative promoter encoding a novel Munc13-4 isoform. Mechanistically, T cell receptor engagement facilitated STAT4-dependent Munc13-4 expression in naive CD8+ T lymphocytes. Collectively, our data demonstrates how chromatin remodeling within an evolutionarily conserved regulatory element in intron 1 of UNC13D regulates the induction of Munc13-4 expression in cytotoxic lymphocytes and suggests that an alternative Munc13-4 isoform is required for lymphocyte cytotoxicity. Thus, mutations associated with primary immunodeficiencies may cause disease by disrupting transcription factor binding.
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| 7. |
- Hart, GT, et al.
(författare)
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Adaptive NK cells in people exposed to Plasmodium falciparum correlate with protection from malaria
- 2019
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 216:6, s. 1280-1290
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Tidskriftsartikel (refereegranskat)abstract
- How antibodies naturally acquired during Plasmodium falciparum infection provide clinical immunity to blood-stage malaria is unclear. We studied the function of natural killer (NK) cells in people living in a malaria-endemic region of Mali. Multi-parameter flow cytometry revealed a high proportion of adaptive NK cells, which are defined by the loss of transcription factor PLZF and Fc receptor γ-chain. Adaptive NK cells dominated antibody-dependent cellular cytotoxicity responses, and their frequency within total NK cells correlated with lower parasitemia and resistance to malaria. P. falciparum–infected RBCs induced NK cell degranulation after addition of plasma from malaria-resistant individuals. Malaria-susceptible subjects with the largest increase in PLZF-negative NK cells during the transmission season had improved odds of resistance during the subsequent season. Thus, antibody-dependent lysis of P. falciparum–infected RBCs by NK cells may be a mechanism of acquired immunity to malaria. Consideration of antibody-dependent NK cell responses to P. falciparum antigens is therefore warranted in the design of malaria vaccines.
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| 8. |
- Lam, MT, et al.
(författare)
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A novel disorder involving dyshematopoiesis, inflammation, and HLH due to aberrant CDC42 function
- 2019
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 216:12, s. 2778-2799
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Tidskriftsartikel (refereegranskat)abstract
- Hemophagocytic lymphohistiocytosis (HLH) is characterized by immune dysregulation due to inadequate restraint of overactivated immune cells and is associated with a variable clinical spectrum having overlap with more common pathophysiologies. HLH is difficult to diagnose and can be part of inflammatory syndromes. Here, we identify a novel hematological/autoinflammatory condition (NOCARH syndrome) in four unrelated patients with superimposable features, including neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and HLH. Patients shared the same de novo CDC42 mutation (Chr1:22417990C>T, p.R186C) and altered hematopoietic compartment, immune dysregulation, and inflammation. CDC42 mutations had been associated with syndromic neurodevelopmental disorders. In vitro and in vivo assays documented unique effects of p.R186C on CDC42 localization and function, correlating with the distinctiveness of the trait. Emapalumab was critical to the survival of one patient, who underwent successful bone marrow transplantation. Early recognition of the disorder and establishment of treatment followed by bone marrow transplant are important to survival.
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