Yenan T Bryceson

University of Bergen, Bergen, Hordaland, Norway

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Publications (75)557.35 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The mechanisms underlying human natural killer (NK) cell phenotypic and functional heterogeneity are unknown. Here, we describe the emergence of diverse subsets of human NK cells selectively lacking expression of signaling proteins after human cytomegalovirus (HCMV) infection. The absence of B and myeloid cell-related signaling protein expression in these NK cell subsets correlated with promoter DNA hypermethylation. Genome-wide DNA methylation patterns were strikingly similar between HCMV-associated adaptive NK cells and cytotoxic effector T cells but differed from those of canonical NK cells. Functional interrogation demonstrated altered cytokine responsiveness in adaptive NK cells that was linked to reduced expression of the transcription factor PLZF. Furthermore, subsets of adaptive NK cells demonstrated significantly reduced functional responses to activated autologous T cells. The present results uncover a spectrum of epigenetically unique adaptive NK cell subsets that diversify in response to viral infection and have distinct functional capabilities compared to canonical NK cell subsets. Copyright © 2015 Elsevier Inc. All rights reserved.
    Immunity 03/2015; 42(3):443-56. DOI:10.1016/j.immuni.2015.02.008 · 19.75 Impact Factor
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    Journal of Allergy and Clinical Immunology 01/2015; DOI:10.1016/j.jaci.2014.11.030 · 11.25 Impact Factor
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    ABSTRACT: Objective. Recently we serendipitously identified a patient with systemic lupus erythematosus (SLE) that harbored autoantibodies to the CD94/NKG2A receptor. Here we investigated the occurrence and function of autoantibodies targeting lectin-like NK cell receptors in SLE.Method. Sera from 203 SLE patients and 90 healthy individuals were analyzed for immunoglobulin-binding to Ba/F3 cells transfected with CD94/NKG2A, CD94/NKG2C or NKG2D by flow cytometry. Identified autoantibodies were characterized with regard to interference with HLA-E-binding, effect on NK cell activation in response to HLA-E transfected K562 cells and capacity to facilitate antibody-dependent cellular cytotoxicity (ADCC). Levels of autoantibodies were determined in longitudinally sampled sera and correlated to disease activity (SLEDAI score) and severity (SLICC/ACR damage index).Results. Anti-CD94/NKG2A autoantibodies were identified in seven patients. Six inhibited, and one augmented, the binding of HLA-E to CD94/NKG2A. Two of these patients' autoantibodies also reacted with the activating CD94/NKG2C receptor, with one inhibiting and one increasing the binding of HLA-E to CD94/NKG2C. None of the sera contained anti-NKG2D autoantibodies. The levels of anti-CD94/NKG2A and anti-CD94/NKG2C autoantibodies correlated with disease activity and a more severe SLE phenotype. Mechanistically, anti-CD94/NKG2A and anti-CD94/NKG2C autoantibodies both interfered with HLA-E-mediated regulation of NK cell activation, and facilitated the elimination of target cells expressing CD94/NKG2A or CD94/NKG2C through ADCC.Conclusions. Anti-CD94/NKG2A and anti-CD94/NKG2C autoantibodies arise in a subset of clinically active SLE patients. Given their capacity to deplete certain NK cell subsets and interfere with particular NK cell function, such autoantibodies may promote the pathogenesis of SLE. This article is protected by copyright. All rights reserved.
    12/2014; DOI:10.1002/art.38999
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    ABSTRACT: Individuals with biallelic truncating PRF1 mutations typically present with fulminant early-onset familial hemophagocytic lymphohistiocytosis (FHL). We report a 19-year-old male with a 5-year history of recurrent fever and headaches progressing to refractory seizures. Brain imaging revealed multiple ring enhancing lesions. Laboratory investigations demonstrated that the patient displayed defective lymphocyte cytotoxicity and carried a homozygous missense PRF1 mutation, c.394G > A (p.Gly132Arg). The patient was successfully treated with chemo-immunotherapy followed by matched related allogeneic hematopoietic stem cell transplantation (HSCT). Our findings demonstrate that prompt HSCT of late-onset FHL with primarily neurological manifestation can reverse central nervous system symptoms and improve long-term outcome. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
    Pediatric Blood & Cancer 12/2014; 61(12). DOI:10.1002/pbc.25166 · 2.35 Impact Factor
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    ABSTRACT: Purpose: The prognosis of malignancy-associated hemophagocytic lymphohistiocytosis (M-HLH) is dismal, and knowledge on its etiology and treatment is limited. The aim of this study was to review treatment and outcome of patients with M-HLH. Methods: Between January 2008 and March 2012, 56 adult patients were referred to the Hematology Center Karolinska with suspicion of HLH. Medical records were retrospectively evaluated with respect to malignancy, clinical and laboratory features, therapy and outcome. Hemophagocytosis was re-evaluated cytohistologically. Results: Of the 56 evaluated patients, 31 fulfilled at least four HLH-2004 criteria and had a concomitant malignancy. Eleven patients (35%) suffered from myeloid malignancies, eleven from B-cell malignancies, eight from T/NK-cell malignancies, whereas one had an endocrine carcinoma. Eight patients debuted with HLH, of which six were later diagnosed with T/NK-cell malignancy. The majority of patients developed HLH subsequently to immunosuppressive therapy. At initial evaluation, hemophagocytosis was found in 17 patients (55%). However, re-evaluation performed by an experienced hematopathologist confirmed hemophagocytosis in 28 patients (90%). All patients displayed hyperferritinemia (max-value range: 1,442–645,291 µg/L). Twenty-one patients received HLH-targeted therapy with IVIG and corticosteroids. Etoposide and cyclosporine were administered in 10 and 8 patients, respectively. Overall survival was 16% (mean follow-up 219 days) and 40-day survival was 58%. The worst prognosis was noted for patients with T-cell malignancies (overall follow-up 0%, mean survival 58 days). There was no difference in survival between patients that fulfilled four versus five or more HLH criteria. Conclusions: Malignancy-associated HLH occurs in patients with hematological malignancies of all cell lineages and occasionally in patients with solid tumors. In patients with T/NK-cell malignancies HLH often preceded the diagnosis of malignancy, whereas in other malignancies HLH predominately followed immunosuppressive therapy. Survival rates were dismal, especially in patients with T/NK-cell malignancies, highlighting the need for improved treatment of adults with M-HLH.
    Pediatric Blood & Cancer 11/2014; 61(11):2132-2133. · 2.56 Impact Factor
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    ABSTRACT: Background Primary hemophagocytic lymphohistiocytosis (HLH) represents a group of inherited hyperinflammatory immunodeficiencies, including familial HLH (FHL), Griscelli syndrome type 2 (GS2), and X-linked lymphoproliferative syndrome (XLP). We previously reported an annual incidence of suspected primary HLH in Sweden 1971–1986 of 0.12 per 100,000 children. Here, we determined if the incidence had increased with concomitant awareness.ProcedureChildren <15 years old presenting with HLH 1987–2006 in Sweden were identified through the national mortality registry as well as by nation-wide inquiries to all pediatric centers. HLH was diagnosed according to the HLH-2004 diagnostic guidelines (in case of missing data of at least three of the eight diagnostic criteria, fulfillment of four was sufficient for inclusion). We defined primary HLH as patients presenting with HLH requiring transplantation or dying of disease.ResultsRemarkably, the minimal annual incidence rate of primary HLH remained 0.12 per 100,000 children, equating to 1.8 per 100,000 live births. Notably, an increased overall survival was observed in 1997–2006, relative to the period 1987–1996. During the subsequent 5-year period, 2007–2011, the incidence of genetically and/or functionally verified primary HLH was 0.15 per 100,000 children per year, suggesting that new assays may aid the identification of patients with primary HLH.Conclusion The annual incidence of primary HLH in Sweden is 0.12–0.15 per 100,000 children per year. Pediatr Blood Cancer 2014;9999: 1–7. © 2014 Wiley Periodicals, Inc.
    Pediatric Blood & Cancer 11/2014; DOI:10.1002/pbc.25308 · 2.35 Impact Factor
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    ABSTRACT: The signal transducer and activator of transcription (STAT) family of transcription factors orchestrate hematopoietic cell differentiation. Recently, mutations in STAT1, STAT5B, and STAT3 have been linked to development of IPEX-like syndrome. Here, we immunologically characterized three patients with de novo activating mutations in the DNA binding or dimerization domains of STAT3 (p.K392R, p.M394T and p.K658N, respectively). The patients displayed multi-organ autoimmunity, lymphoproliferation, and delayed-onset mycobacterial disease. Immunologically, we noted hypogammaglobulinemia with terminal B cell maturation arrest, dendritic cell deficiency, peripheral eosinopenia, increased double-negative (CD4(-)CD8(-)) T cells, and decreased NK, Th17, and regulatory T cell numbers. Notably, the patient harboring the K392R mutation developed T cell LGL leukemia at age 14. Our results broaden the spectrum of phenotypes caused by activating STAT3 mutations, highlight the role of STAT3 in the development and differentiation of multiple immune cell lineages, and strengthen the link between the STAT family of transcription factors and autoimmunity.
    Blood 10/2014; DOI:10.1182/blood-2014-04-570101 · 9.78 Impact Factor
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    ABSTRACT: Histiocytic disorders are rare entities that are becoming more recognized as our understanding of the molecular pathogenesis lead to novel diagnostic tests and targeted drug development. A symposium held at the American Society of Pediatric Hematology/Oncology (ASPHO) 2013 Annual Meeting discussed new insights into histiocytic disorders. This review highlights the symposium presentations, divided into three sections encompassing Langerhans cell histiocytosis (LCH), hemophagocytic lymphohistiocytosis (HLH) and Rosai Dorfman disease (RDD) including subsections on pathogenesis, clinical diagnostic criteria and novel insights into treatment. Details of other histiocytic disorders as well as the standard treatment guidelines have been published elsewhere and are beyond the scope of this discussion [Haupt et al. (2013). Pediatr Blood Cancer 60:175–184; Henter et al. (2007). Pediatr Blood Cancer 48:124–131]. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
    Pediatric Blood & Cancer 07/2014; 61(7). DOI:10.1002/pbc.25017 · 2.35 Impact Factor
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    Konrad Krzewski, Yenan T Bryceson
    Frontiers in Immunology 06/2014; 5:279. DOI:10.3389/fimmu.2014.00279
  • Journal of Allergy and Clinical Immunology 05/2014; DOI:10.1016/j.jaci.2014.04.026 · 11.25 Impact Factor
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    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.
    Journal of Experimental Medicine 05/2014; 211(6). DOI:10.1084/jem.20131131 · 13.91 Impact Factor
  • Frank Cichocki, Ewa Sitnicka, Yenan T. Bryceson
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    ABSTRACT: Bone marrow-derived natural killer (NK) cells constitute the major subset of cytotoxic lymphocytes in peripheral blood. They provide innate defense against intracellular infection or malignancy and contribute to immune homeostasis. Large numbers of NK cells are also present in tissues, including the liver and uterus, where they can mediate immunosurveillance but also play important roles in tissue remodeling and vascularization. Here, we review the pathways involved in NK cell lineage commitment and differentiation, discussing relationships to other lymphocyte populations and highlighting genetic determinants. Characterizing NK cells from distinct tissues and during infections have revealed subset specializations, reflecting inherent cellular plasticity. In this context, we discuss how different environmental and inflammatory stimuli may shape NK cells. Particular emphasis is placed on genes identified as being critical for NK cell development, differentiation, and function from studies of model organisms or associations with disease. Such studies are also revealing important cellular redundancies. Here, we provide a view of the genetic framework constraining NK cell development and function, pinpointing molecules required for these processes but also underscoring plasticity and redundancy that may underlie robust immunological function. With this view, built in redundancy may highlight the importance of NK cells to immunity.
    Seminars in Immunology 04/2014; DOI:10.1016/j.smim.2014.02.003 · 6.12 Impact Factor
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    ABSTRACT: Natural killer (NK) cells mediate defense against neoplastic as well as infected cells. Yet, how their effector functions are affected by the large variety of pharmacological compounds commonly in use has not been investigated systematically. Here, we screened 1,200 in-use or previously approved drugs for their biological effect on freshly isolated human peripheral blood-derived NK cells. Mimicking antibody-dependent cellular cytotoxicity (ADCC), known to be important in antibody-based immunotherapies against, e.g., human malignancies, the cells were stimulated by Fc-receptor (CD16) engagement. Cellular responses were assessed by flow cytometry. Fifty-six compounds that significantly inhibited and twelve that enhanced one or more of the readouts of adhesion, exocytosis, and chemokine production were identified and confirmed as hits. Among the confirmed inhibitors, 80 % could be assigned to one of seven major pharmacological classes. These classes were β2-adrenergic agonists, prostaglandins, phosphodiesterase-4 inhibitors, Ca(2+)-channel blockers, histamine H1-receptor antagonists, serotonin/dopamine receptor antagonists, and topoisomerase inhibitors that displayed distinct inhibitory patterns on NK cell responses. Among observed enhancers, interestingly, two ergosterol synthesis inhibitors were identified that specifically promoted exocytosis. In summary, these results provide a comprehensive knowledge base of the effect known drugs have on NK cells. More specifically, they provide an overview of drugs that may modulate NK cell-mediated ADCC in the context of clinical immunotherapies.
    Cancer Immunology and Immunotherapy 03/2014; DOI:10.1007/s00262-014-1539-6 · 3.64 Impact Factor
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    ABSTRACT: In experimental settings, lymphocyte cytotoxicity has been recognized as a central mechanism for immune defense against infected and neoplastic cells. More recently, molecular determinants of lymphocyte cytotoxicity have been identified through studies of rare, inherited hyperinflammatory and lymphoproliferative syndromes that include hemophagocytic lymphohistiocytosis (HLH). These studies have unraveled a set of genes pivotal for the biogenesis and directed release of perforin-containing lysosomes that mediate target cell killing, in addition to other pathways including Fas that also contribute to induction of cell death. Furthermore, studies of such human primary immunodeficiencies have highlighted non-redundant roles of perforin for maintenance of immune homeostasis. Besides providing mechanistic insights to lymphocyte cytotoxicity, studies of individuals with rare hyperinflammatory diseases are highlighting the relevance of lymphocyte cytotoxicity to more common human diseases. It is increasingly recognized that mutations abrogating lymphocyte cytotoxicity not only cause HLH, but also are associated with susceptibility to cancer and autoimmune syndromes. In addition, patients may initially present with neurological symptoms or severe infectious disease masquerading as variable immunodeficiency syndrome. Here, we highlight new knowledge regarding the molecular mechanisms regulating lymphocyte cytotoxicity and review how mutations in genes associated with HLH cause disease. We also discuss the wider implications of impairments in lymphocyte cytotoxicity for human disease predisposition.
    Experimental Cell Research 03/2014; DOI:10.1016/j.yexcr.2014.03.014 · 3.37 Impact Factor
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    ABSTRACT: Reporting a clinical case with a novel mutation in the signal transducer and activator of transcription 3 (STAT3) gene resulting in autosomal dominant hyper-immunoglobulin E syndrome (AD-HIES). Here we also had the opportunity to perform in-depth immunologic investigations to further understand the immunopathology of this primary immunodeficiency. The patient, a baby boy, was clinically assessed according to the scoring system developed by Grimbacher et al. and STAT3 was investigated by DNA sequencing. Immunologic work-up consisted of lymphocyte phenotyping and proliferation assays, measurement of soluble mediators and routine investigations. According to the Grimbacher score the patient was likely to have AD-HIES and a novel heterozygous STAT3 mutation (c.1110-3C>A), causing a splice error, was identified. Lymphocyte phenotyping revealed decreased numbers of interleukin (IL)-17 producing T-helper lymphocytes and aberrant B-lymphocyte subsets. Proliferative in vitro lymphocyte responses against C. albicans, staphylococcal enterotoxins and pokeweed mitogen were supernormal at presentation, whereas only the elevated response to pokeweed mitogen persisted. The soluble mediators IL-5, -10, -12, -13, -15 and granulocyte colony stimulatory factor were elevated in serum. A novel heterozygous STAT3 mutation causing defective splicing of exon 12 was identified. Lymphocyte phenotyping revealed deranged subpopulations. Despite the clinical picture with severe C. albicans and staphylococcal infections, the patient's lymphocytes mounted responses to these pathogens. The hypereosinophilia and high immunoglobulin E levels might partly be explained by elevated IL-5 and -13 as a result of lack of negative feedback from defective STAT3 signaling.
    Journal of Clinical Immunology 03/2014; 34(4). DOI:10.1007/s10875-014-0011-x · 2.65 Impact Factor
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    ABSTRACT: Familial hemophagocytic lymphohistiocytosis (FHL) is an often-fatal hyperinflammatory disorder caused by autosomal recessive mutations in PRF1, UNC13D, STX11, and STXBP2. We identified a homozygous STX11 mutation, c.173T > C (p.L58P), in three patients presenting clinically with hemophagocytic lymphohistiocytosis from unrelated Pakistani families. The mutation yields an amino acid substitution in the N-terminal Habc domain of syntaxin-11 and resulted in defective natural killer cell degranulation. Notably, syntaxin-11 expression was decreased in patient cells. However, in an ectopic expression system, syntaxin-11 L58P was expressed at levels comparable to wild-type syntaxin-11, but did not bind Munc18-2. Moreover, another N-terminal syntaxin-11 mutant, R4A, also did not bind Munc18-2. Thus, we have identified a novel missense STX11 mutation causative of FHL type 4. The syntaxin-11 R4A and L58P mutations reveal that both the N-terminus and Habc domain of syntaxin-11 are required for binding to Munc18-2, implying similarity to the dynamic binary binding of neuronal syntaxin-1 to Munc18-1.
    Frontiers in Immunology 01/2014; 4:515. DOI:10.3389/fimmu.2013.00515
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    ABSTRACT: Constitutive heterozygous GATA2 mutation is associated with deafness, lymphedema, mononuclear cytopenias, infection, myelodysplasia (MDS) and AML. Here we describe a cross-sectional analysis of 24 patients and 6 relatives with 14 different frameshift or substitution mutations of GATA2. A pattern of mononuclear cytopenia (DCML deficiency) with elevated Flt3 ligand (Flt3L) was observed in all 20 patients phenotyped, including patients with Emberger's syndrome, monoMAC, and MDS. Four unaffected relatives had a normal phenotype indicating that cellular deficiency may evolve over time or is incompletely penetrant, while 2 developed subclinical cytopenias or elevated Flt3L. Patients with GATA2 mutation maintained higher hemoglobin, neutrophils and platelets and were younger than controls with acquired MDS and wild-type GATA2. Frame-shift mutations were associated with earlier age of clinical presentation than substitution mutations. Elevated Flt3L, loss of bone marrow progenitors and clonal myelopoiesis were early signs of disease evolution. Clinical progression was associated with increasingly elevated Flt3L, depletion of transitional B cells, CD56(bright) NK cells and naïve T cells and accumulation of terminally differentiated NK and CD8(+) memory T cells. These studies provide a framework for clinical and laboratory monitoring of patients with GATA2 mutation and may inform therapeutic decision making.
    Blood 12/2013; DOI:10.1182/blood-2013-07-517151 · 9.78 Impact Factor
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    ABSTRACT: During childhood, infections with cytomegalovirus (CMV) and Epstein-Barr virus (EBV) can occur in close temporal proximity. Active as well as latent CMV infection is associated with enlarged subsets of differentiated NK- and cytotoxic T cells. How EBV infection may influence CMV-driven immune differentiation is not known. Here we found that EBV co-infection selectively influenced the NK-cell compartment of CMV-seropositive (CMV(+)) children. Co-infected children had significantly higher proportions of peripheral-blood NKG2C(+) NK cells than CMV(+)EBV(-) children. Ex vivo NK-cell degranulation after target cell stimulation and plasma IL-15 levels were significantly higher in CMV(+) children. EBV co-infection related with the highest levels of plasma IL-15 and IL-12p70. Remarkably, in vitro EBV infection of peripheral blood mononuclear cells (PBMC) from EBV(-)CMV(+) children increased NKG2C(+) NK-cell proportions. A similar tendency was seen in co-cultures of PBMC with EBV(+) lymphoblastoid B-cell lines (LCL) and IL-15. Following K562 challenge, NKG2C(+) NK cells excelled in regards to degranulation and production of IFN-γ, regardless of previous co-culture with LCL. Taken together, our data suggests that dual latency with these herpesviruses during childhood could contribute to an in vivo environment supporting differentiation and maintenance of distinct NK-cell populations. This viral imprint may affect subsequent immune responses through altered distributions of effector cells.
    Journal of Virology 10/2013; 87(24). DOI:10.1128/JVI.02382-13 · 4.65 Impact Factor
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    ABSTRACT: Patients with systemic lupus erythematosus (SLE) display an activated type I IFN system due to unceasing IFN-α release from plasmacytoid dendritic cells (pDCs) stimulated by nucleic acid-containing immune complexes (ICs). NK cells strongly promote the IFN-α production by pDCs; therefore, we investigated surface molecules that could be involved in the pDC-NK cell cross-talk. In human PBMCs stimulated with RNA-containing ICs (RNA-ICs), the expression of the signaling lymphocyte activation molecule (SLAM) family receptors CD319 and CD229 on pDCs and CD319 on CD56(dim) NK cells was selectively increased. Upregulation of CD319 and CD229 on RNA-IC-stimulated pDCs was induced by NK cells or cytokines (e.g., GM-CSF, IL-3). IFN-α-producing pDCs displayed a higher expression of SLAM molecules compared with IFN-α(-) pDCs. With regard to signaling downstream of SLAM receptors, pDCs expressed SHIP-1, SHP-1, SHP-2, and CSK but lacked SLAM-associated protein (SAP) and Ewing's sarcoma-activated transcript 2 (EAT2), indicating that these receptors may act as inhibitory receptors on pDCs. Furthermore, pDCs from patients with SLE had decreased expression of CD319 on pDCs and CD229 on CD56(dim) NK cells, but RNA-IC stimulation increased CD319 and CD229 expression. In conclusion, this study reveals that the expression of the SLAM receptors CD319 and CD229 is regulated on pDCs and NK cells by lupus ICs and that the expression of these receptors is specifically altered in SLE. These results, together with the observed genetic association between the SLAM locus and SLE, suggest a role for CD319 and CD229 in the SLE disease process.
    The Journal of Immunology 08/2013; 191(6). DOI:10.4049/jimmunol.1301022 · 5.36 Impact Factor
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    ABSTRACT: Cytotoxic lymphocytes are important for immune responses against viral infections and cancer. They can kill target cells through the release of cytotoxic granules without themselves getting harmed in the process. Because the lysosomal associated membrane proteins (LAMPs) appear on the cell surface following cytotoxic granule exocytosis, we hypothesized that some of these proteins might be involved in transiently protecting cytotoxic lymphocytes from suicide. Intracellular expression of CD107a/LAMP-1, and to a lesser extent that of CD107b/LAMP-2, correlated with lymphocyte cytotoxic granule content. Engineered surface expression of CD107a/LAMP-1, but not of CD107b/LAMP-2, reduced the granule-mediated killing of transfected target cells. This was dependent on glycosylation of the CD107a/LAMP-1 hinge. Moreover, surface expression of CD107a/LAMP-1 reduced binding of perforin to cells. Importantly, knockdown of CD107a/LAMP-1 in primary human NK cells and deficiency of CD107a/LAMP-1 in mice resulted in increased NK cell apoptosis upon target cell-induced degranulation. Thus, our data support a novel role of CD107a/LAMP-1 in the protection of NK cells from degranulation-associated suicide, which may represent a general mechanism to transiently limit self-destruction by cytotoxic lymphocytes upon target cell killing.
    Blood 07/2013; 122(8). DOI:10.1182/blood-2012-07-441832 · 9.78 Impact Factor

Publication Stats

3k Citations
557.35 Total Impact Points


  • 2014
    • University of Bergen
      • Department of Clinical Science
      Bergen, Hordaland, Norway
  • 2008–2014
    • Karolinska Institutet
      • Center for Infectious Medicine
      Solna, Stockholm, Sweden
    • National Institutes of Health
      Maryland, United States
  • 2007–2014
    • Karolinska University Hospital
      • Center for Infectious Medicine (CIM)
      Tukholma, Stockholm, Sweden
    • Leiden University
      Leyden, South Holland, Netherlands
  • 2011
    • Freie Universität Berlin
      • Division of Biochemistry
      Berlin, Land Berlin, Germany
  • 2002–2009
    • National Institute of Allergy and Infectious Diseases
      • Laboratory of Immunoregulation
      Maryland, United States
  • 2005
    • University of Oslo
      • Department of Anatomy
      Kristiania (historical), Oslo, Norway