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Tomaz D, Pereira PM, Guerra N, Dyson J, Gould K, Henriques R. Nanoscale Colocalization of NK Cell Activating and Inhibitory Receptors Controls Signal Integration. Front Immunol 2022; 13:868496. [PMID: 35720315 PMCID: PMC9198454 DOI: 10.3389/fimmu.2022.868496] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Natural killer (NK) cell responses depend on the balance of signals from inhibitory and activating receptors. However, how the integration of antagonistic signals occurs upon NK cell-target cell interaction is not fully understood. Here we provide evidence that NK cell inhibition via the inhibitory receptor Ly49A is dependent on its relative colocalization at the nanometer scale with the activating receptor NKG2D upon immune synapse (IS) formation. NKG2D and Ly49A signal integration and colocalization were studied using NKG2D-GFP and Ly49A-RFP-expressing primary NK cells, forming ISs with NIH3T3 target cells, with or without the expression of single-chain trimer (SCT) H2-Dd and an extended form of SCT H2-Dd-CD4 MHC-I molecules. Nanoscale colocalization was assessed by Förster resonance energy transfer between NKG2D-GFP and Ly49A-RFP and measured for each synapse. In the presence of their respective cognate ligands, NKG2D and Ly49A colocalize at the nanometer scale, leading to NK cell inhibition. However, increasing the size of the Ly49A ligand reduced the nanoscale colocalization with NKG2D, consequently impairing Ly49A-mediated inhibition. Thus, our data shows that NK cell signal integration is critically dependent on the dimensions of NK cell ligand-receptor pairs by affecting their relative nanometer-scale colocalization at the IS. Our results together suggest that the balance of NK cell signals and NK cell responses is determined by the relative nanoscale colocalization of activating and inhibitory receptors in the immune synapse.
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Affiliation(s)
- David Tomaz
- Department of Immunology, Wright-Fleming Institute, Imperial College London, London, United Kingdom
- Department of Immunology, Hammersmith Hospital, Imperial College London, London, United Kingdom
| | - Pedro Matos Pereira
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Nadia Guerra
- Division of Cell and Molecular Biology, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
| | - Julian Dyson
- Department of Immunology, Hammersmith Hospital, Imperial College London, London, United Kingdom
| | - Keith Gould
- Department of Immunology, Wright-Fleming Institute, Imperial College London, London, United Kingdom
| | - Ricardo Henriques
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Division of Infection and Immunity, University College London, London, United Kingdom
- Optical Cell Biology Lab, Instituto Gulbenkian de Ciência, Oeiras, Portugal
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Barragan-Galvez JC, Gonzalez-Orozco M, Hernandez-Flores A, Maravillas-Montero JL, Chavez-Guerrero Y, Ortiz-Navarrete V. Prokaryotic Expression of the Immunoglobulin's Domains of CRTAM to Characterize a Monoclonal Antibody. Protein J 2020; 39:224-231. [PMID: 32300914 DOI: 10.1007/s10930-020-09896-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Class-I restricted T cell-associated molecule (CRTAM) is a member of the immunoglobulin superfamily, and it is closely related to nectin-like protein. CRTAM is expressed in activated CD8 T cells, NKT cells, NK cells and in a subpopulation CD4 T cells. In this study, we produce as recombinant proteins, the Ig-domains of CRTAM (IgV-IgC), the IgV, and the IgC. These proteins were successfully purified in the soluble fraction only if the stalk region was included. The recombinant CRTAM recognizes its ligand nectin-like 2 in a cell-free system. We also demonstrate that the IgC domain of CRTAM is recognized by the anti-hCRTAM monoclonal antibody C8 with a 0.62 nM affinity. In conclusion, the stalk region of CRTAM provides solubility for the expression of its Ig-domains as recombinant proteins.
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Affiliation(s)
- Juan Carlos Barragan-Galvez
- Biomedical Sciences Program, National Autonomous University of Mexico, Circuito Interior s/n, Cd. Universitaria, Mexico City, Mexico
| | - Maria Gonzalez-Orozco
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV), Av. IPN 2508. Col. San Pedro Zacatenco, Gustavo A Madero, 07360, Mexico City, Mexico.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | | | - Jose Luis Maravillas-Montero
- Research Support Network, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Mexico City, Mexico
| | - Yedhani Chavez-Guerrero
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV), Av. IPN 2508. Col. San Pedro Zacatenco, Gustavo A Madero, 07360, Mexico City, Mexico
| | - Vianney Ortiz-Navarrete
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV), Av. IPN 2508. Col. San Pedro Zacatenco, Gustavo A Madero, 07360, Mexico City, Mexico.
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3
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Ly49R activation receptor drives self-MHC-educated NK cell immunity against cytomegalovirus infection. Proc Natl Acad Sci U S A 2019; 116:26768-26778. [PMID: 31843910 DOI: 10.1073/pnas.1913064117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Natural killer (NK) cells mediate vital control of cancer and viral infection. They rely on MHC class I (MHC I)-specific self-receptors to identify and lyse diseased cells without harming self-MHC I-bearing host cells. NK cells bearing inhibitory self-receptors for host MHC I also undergo education, referred to as licensing, which causes them to become more responsive to stimulation via activation receptor signaling. Previous work has shown that licensed NK cells selectively expand during virus infections and they are associated with improved clinical response in human patients experiencing certain chronic virus infections, including HIV and hepatitis C virus. However, the importance of inhibitory self-receptors in NK-mediated virus immunity is debated as they also limit signals in NK cells emanating from virus-specific activation receptors. Using a mouse model of MHC I-dependent (H-2Dk) virus immunity, we discovered that NK cells depend on the Ly49G2 inhibitory self-receptor to mediate virus control, which coincided with host survival during murine cytomegalovirus infection. This antiviral effect further requires active signaling in NK cells via the Ly49R activation receptor that also binds H-2Dk In tandem, these functionally discordant Ly49 self-receptors increase NK cell proliferation and effector activity during infection, resulting in selective up-regulation of CD25 and KLRG1 in virus-specific Ly49R+ Ly49G2+ NK cells. Our findings establish that paired self-receptors act as major determinants of NK cell-mediated virus sensing and immunity.
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SLAM family receptors in natural killer cells - Mediators of adhesion, activation and inhibition via cis and trans interactions. Clin Immunol 2018; 204:37-42. [PMID: 30359773 DOI: 10.1016/j.clim.2018.10.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 02/06/2023]
Abstract
SLAM family receptors are important for the fine-tuning of immune reactions. Their expression is restricted to cells of hematopoietic origin and most SLAM family receptors are their own ligand. Here we review how these receptors are involved in regulating the functions of Natural Killer (NK) cells. We discuss that promoting cellular adhesion may be a main function of SLAM family receptors in NK cells. The homophilic interactions of SLAM family receptors can not only occur in trans between different cells, but also in cis on the surface of the same cell. This cis interaction additionally modulates the function of the receptors and subsequently affects the activities of NK cells. Finally, SLAM-family receptors can also mediate inhibitory signals under certain conditions. These inhibitory signals can contribute to the functional maturation of NK cells during NK cell education. Therefore, SLAM family receptors are critically involved in many aspects of NK cell functionality.
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Claus M, Wingert S, Watzl C. Modulation of natural killer cell functions by interactions between 2B4 and CD48 in cis and in trans. Open Biol 2016; 6:rsob.160010. [PMID: 27249817 PMCID: PMC4892432 DOI: 10.1098/rsob.160010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/24/2016] [Indexed: 01/23/2023] Open
Abstract
SLAM-related receptors (SRRs) are important modulators of immune cell function. While most SRRs are homophilic, 2B4 (CD244) interacts with CD48, a GPI-anchored protein expressed on many haematopoietic cells. Here we show that natural killer (NK) cell-expressed 2B4 not only binds in trans to CD48 on neighbouring cells but also interacts in cis with CD48 on the same cell. 2B4 uses the same binding site to interact with CD48 in cis and in trans and structural flexibility of 2B4 is necessary for the cis interaction. Furthermore, the cis interaction is sufficient to induce basal phosphorylation of 2B4. However, cis interaction reduces the ability of 2B4 to bind CD48 in trans. As a consequence, stimulation-dependent phosphorylation of 2B4 upon binding to CD48 positive target cells is reduced. Interfering with the cis interaction therefore enhanced the lysis of CD48-expressing tumour cells. These data show that the density of 2B4 and CD48 on both the NK cell and the potential target cell modulates NK cell activity.
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Affiliation(s)
- Maren Claus
- Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund (IfADo) Dortmund, Germany
| | - Sabine Wingert
- Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund (IfADo) Dortmund, Germany
| | - Carsten Watzl
- Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund (IfADo) Dortmund, Germany
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Bagawath-Singh S, Staaf E, Stoppelenburg AJ, Spielmann T, Kambayashi T, Widengren J, Johansson S. Cytokines Induce Faster Membrane Diffusion of MHC Class I and the Ly49A Receptor in a Subpopulation of Natural Killer Cells. Front Immunol 2016; 7:16. [PMID: 26870035 PMCID: PMC4740373 DOI: 10.3389/fimmu.2016.00016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/14/2016] [Indexed: 12/20/2022] Open
Abstract
Cytokines have the potential to drastically augment immune cell activity. Apart from altering the expression of a multitude of proteins, cytokines also affect immune cell dynamics. However, how cytokines affect the molecular dynamics within the cell membrane of immune cells has not been addressed previously. Molecular movement is a vital component of all biological processes, and the rate of motion is, thus, an inherent determining factor for the pace of such processes. Natural killer (NK) cells are cytotoxic lymphocytes, which belong to the innate immune system. By fluorescence correlation spectroscopy, we investigated the influence of cytokine stimulation on the membrane density and molecular dynamics of the inhibitory receptor Ly49A and its ligand, the major histocompatibility complex class I allele H-2Dd, in freshly isolated murine NK cells. H-2Dd was densely expressed and diffused slowly in resting NK cells. Ly49A was expressed at a lower density and diffused faster. The diffusion rate in resting cells was not altered by disrupting the actin cytoskeleton. A short-term stimulation with interleukin-2 or interferon-α + β did not change the surface density of moving H-2Dd or Ly49A, despite a slight upregulation at the cellular level of H-2Dd by interferon-α + β, and of Ly49A by IL-2. However, the molecular diffusion rates of both H-2Dd and Ly49A increased significantly. A multivariate analysis revealed that the increased diffusion was especially marked in a subpopulation of NK cells, where the diffusion rate was increased around fourfold compared to resting NK cells. After IL-2 stimulation, this subpopulation of NK cells also displayed lower density of Ly49A and higher brightness per entity, indicating that Ly49A may homo-cluster to a larger extent in these cells. A faster diffusion of inhibitory receptors could enable a faster accumulation of these molecules at the immune synapse with a target cell, eventually leading to a more efficient NK cell response. It has previously been assumed that cytokines regulate immune cells primarily via alterations of protein expression levels or posttranslational modifications. These findings suggest that cytokines may also modulate immune cell efficiency by increasing the molecular dynamics early on in the response.
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Affiliation(s)
- Sunitha Bagawath-Singh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet , Stockholm , Sweden
| | - Elina Staaf
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet , Stockholm , Sweden
| | - Arie Jan Stoppelenburg
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet , Stockholm , Sweden
| | - Thiemo Spielmann
- Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology , Stockholm , Sweden
| | - Taku Kambayashi
- Department of Pathology and Laboratory Medicine, Division of Rheumatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jerker Widengren
- Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology , Stockholm , Sweden
| | - Sofia Johansson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet , Stockholm , Sweden
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Chen P, Aguilar OA, Rahim MMA, Allan DSJ, Fine JH, Kirkham CL, Ma J, Tanaka M, Tu MM, Wight A, Kartsogiannis V, Gillespie MT, Makrigiannis AP, Carlyle JR. Genetic investigation of MHC-independent missing-self recognition by mouse NK cells using an in vivo bone marrow transplantation model. THE JOURNAL OF IMMUNOLOGY 2015; 194:2909-18. [PMID: 25681346 DOI: 10.4049/jimmunol.1401523] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
MHC-I-specific receptors play a vital role in NK cell-mediated "missing-self" recognition, which contributes to NK cell activation. In contrast, MHC-independent NK recognition mechanisms are less well characterized. In this study, we investigated the role of NKR-P1B:Clr-b (Klrb1:Clec2d) interactions in determining the outcome of murine hematopoietic cell transplantation in vivo. Using a competitive transplant assay, we show that Clr-b(-/-) bone marrow (BM) cells were selectively rejected by wild-type B6 recipients, to a similar extent as H-2D(b-/-) MHC-I-deficient BM cells. Selective rejection of Clr-b(-/-) BM cells was mitigated by NK depletion of recipient mice. Competitive rejection of Clr-b(-/-) BM cells also occurred in allogeneic transplant recipients, where it was reversed by selective depletion of NKR-P1B(hi) NK cells, leaving the remaining NKR-P1B(lo) NK subset and MHC-I-dependent missing-self recognition intact. Moreover, competitive rejection of Clr-b(-/-) hematopoietic cells was abrogated in Nkrp1b-deficient recipients, which lack the receptor for Clr-b. Of interest, similar to MHC-I-deficient NK cells, Clr-b(-/-) NK cells were hyporesponsive to both NK1.1 (NKR-P1C)-stimulated and IL-12/18 cytokine-primed IFN-γ production. These findings support a unique and nonredundant role for NKR-P1B:Clr-b interactions in missing-self recognition of normal hematopoietic cells and suggest that optimal BM transplant success relies on MHC-independent tolerance mechanisms. These findings provide a model for human NKR-P1A:LLT1 (KLRB1:CLEC2D) interactions in human hematopoietic cell transplants.
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Affiliation(s)
- Peter Chen
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Oscar A Aguilar
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Mir Munir A Rahim
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - David S J Allan
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Jason H Fine
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Christina L Kirkham
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Jaehun Ma
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Miho Tanaka
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada
| | - Megan M Tu
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Andrew Wight
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Vicky Kartsogiannis
- Prince Henry's Institute, Monash Medical Centre, Clayton, Victoria 3168, Australia; and
| | - Matthew T Gillespie
- Prince Henry's Institute, Monash Medical Centre, Clayton, Victoria 3168, Australia; and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3168, Australia
| | - Andrew P Makrigiannis
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada;
| | - James R Carlyle
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario M4N 3M5, Canada;
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Kirkham CL, Carlyle JR. Complexity and Diversity of the NKR-P1:Clr (Klrb1:Clec2) Recognition Systems. Front Immunol 2014; 5:214. [PMID: 24917862 PMCID: PMC4041007 DOI: 10.3389/fimmu.2014.00214] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/28/2014] [Indexed: 11/26/2022] Open
Abstract
The NKR-P1 receptors were identified as prototypical natural killer (NK) cell surface antigens and later shown to be conserved from rodents to humans on NK cells and subsets of T cells. C-type lectin-like in nature, they were originally shown to be capable of activating NK cell function and to recognize ligands on tumor cells. However, certain family members have subsequently been shown to be capable of inhibiting NK cell activity, and to recognize proteins encoded by a family of genetically linked C-type lectin-related ligands. Some of these ligands are expressed by normal, healthy cells, and modulated during transformation, infection, and cellular stress, while other ligands are upregulated during the immune response and during pathological circumstances. Here, we discuss historical and recent developments in NKR-P1 biology that demonstrate this NK receptor–ligand system to be far more complex and diverse than originally anticipated.
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Affiliation(s)
- Christina L Kirkham
- Department of Immunology, University of Toronto, Sunnybrook Research Institute , Toronto, ON , Canada
| | - James R Carlyle
- Department of Immunology, University of Toronto, Sunnybrook Research Institute , Toronto, ON , Canada
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Chen P, Bélanger S, Aguilar OA, Zhang Q, St-Laurent A, Rahim MMA, Makrigiannis AP, Carlyle JR. Analysis of the mouse 129-strain Nkrp1-Clr gene cluster reveals conservation of genomic organization and functional receptor-ligand interactions despite significant allelic polymorphism. Immunogenetics 2011; 63:627-40. [PMID: 21667046 DOI: 10.1007/s00251-011-0542-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 05/23/2011] [Indexed: 11/28/2022]
Abstract
The Nkrp1 (Klrb) family of NK cell receptors and their genetically linked Clr (Clec2) ligands are conserved between rodents and humans. Nonetheless, certain mouse and rat Nkrp1 genes exhibit significant allelic polymorphism between inbred strains. We previously demonstrated that the Nkrp1-Clr recognition system is genetically and functionally conserved between the B6 and BALB/c strains, with focused sequence divergence evident in certain genes (e.g., Nkrp1b,c). Here, we extend this finding by mapping the 129-strain Nkrp1-Clr gene cluster, which is structurally conserved yet displays significant sequence divergence relative to the B6 haplotype. In addition, we show that 129-strain NK cells possess comparable Nkrp1 and Clr transcript expression, and characterize several NKR-P1:Clr interactions that are functionally conserved between the B6 and 129 strains, including documented and novel receptor-ligand pairs. Thus, despite significant allelic polymorphism observed in the Nkrp1-Clr region, the overall genetic organization and functional repertoire appear to be conserved among mouse strains, in contrast to the striking variation observed in the corresponding Ly49 region. These data extend our knowledge of the complex genetically linked Nkrp1-Clr NK recognition system in mice.
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Affiliation(s)
- Peter Chen
- Department of Immunology, University of Toronto, Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON, M4N 3M5, Canada
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Babić M, Pyzik M, Zafirova B, Mitrović M, Butorac V, Lanier LL, Krmpotić A, Vidal SM, Jonjić S. Cytomegalovirus immunoevasin reveals the physiological role of "missing self" recognition in natural killer cell dependent virus control in vivo. J Exp Med 2010; 207:2663-73. [PMID: 21078887 PMCID: PMC2989764 DOI: 10.1084/jem.20100921] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Accepted: 10/18/2010] [Indexed: 12/14/2022] Open
Abstract
Cytomegaloviruses (CMVs) are renowned for interfering with the immune system of their hosts. To sidestep antigen presentation and destruction by CD8(+) T cells, these viruses reduce expression of major histocompatibility complex class I (MHC I) molecules. However, this process sensitizes the virus-infected cells to natural killer (NK) cell-mediated killing via the "missing self" axis. Mouse cytomegalovirus (MCMV) uses m152 and m06 encoded proteins to inhibit surface expression of MHC I molecules. In addition, it encodes another protein, m04, which forms complexes with MHC I and escorts them to the cell surface. This mechanism is believed to prevent NK cell activation and killing by restoring the "self" signature and allowing the engagement of inhibitory Ly49 receptors on NK cells. Here we show that MCMV lacking m04 was attenuated in an NK cell- and MHC I-dependent manner. NK cell-mediated control of the infection was dependent on the presence of NK cell subsets expressing different inhibitory Ly49 receptors. In addition to providing evidence for immunoevasion strategies used by CMVs to avoid NK cell control via the missing-self pathway, our study is the first to demonstrate that missing self-dependent NK cell activation is biologically relevant in the protection against viral infection in vivo.
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Affiliation(s)
- Marina Babić
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
| | - Michal Pyzik
- Department of Human Genetics, McGill University, Montreal, QC H3A 1B1, Canada
| | - Biljana Zafirova
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
| | - Maja Mitrović
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
| | - Višnja Butorac
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
| | - Lewis L. Lanier
- Department of Microbiology and Immunology and the Cancer Research Institute, University of California, San Francisco, San Francisco, CA 94115
| | - Astrid Krmpotić
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
| | - Silvia M. Vidal
- Department of Human Genetics, McGill University, Montreal, QC H3A 1B1, Canada
| | - Stipan Jonjić
- Department of Histology and Embryology, Medical Faculty, University of Rijeka, 51000 Rijeka, Croatia
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Abstract
NK cell responses are regulated by a balance of inhibitory and activating signals, reflecting the net effect of interactions between receptors and ligands on target and effector cell surfaces. The identification of ligands for orphan NK cell receptors is key to enhancing our understanding of NK cell biology. Here we describe a strategy (protocol) for the identification of ligands for orphan NK cell receptors using signaling reporter cells in combination with a virus rescue system.
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