651
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Abstract
Natural killer (NK) cells play a crucial role in limiting the severity of diseases caused by a range of viruses. Recent data have shown that the effector functions of NK cells can be specifically stimulated when NK cell activation receptors engage cellular major histocompatibility complex (MHC) class I-like ligands induced after infection or by specific viral gene products. However, to counter this NK cell response viruses have evolved an array of strategies to subvert efficient NK cell activation. These data indicate that the balance of host NK cell responses and viral NK cell escape mechanisms can be strategically poised as each strives for survival.
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Affiliation(s)
- Anthony A Scalzo
- Dept of Microbiology, School of Biomedical and Chemical Sciences, Queen Elizabeth II Medical Centre, The University of Western Australia, Nedlands, WA, Australia.
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652
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Markel G, Wolf D, Hanna J, Gazit R, Goldman-Wohl D, Lavy Y, Yagel S, Mandelboim O. Pivotal role of CEACAM1 protein in the inhibition of activated decidual lymphocyte functions. J Clin Invest 2002. [DOI: 10.1172/jci0215643] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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653
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Colucci F, Di Santo JP, Leibson PJ. Natural killer cell activation in mice and men: different triggers for similar weapons? Nat Immunol 2002; 3:807-13. [PMID: 12205470 DOI: 10.1038/ni0902-807] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The signaling pathways that regulate B and T lymphocytes are remarkably conserved between humans and mice. However, recent evidence suggests that the pathways regulating natural killer (NK) cell activation may actually differ between these two species. We discuss the controversies in the field and propose that this divergence could be deceptive: despite some clear differences between human and mouse NK cell receptors, the many ways of activating NK cells and their functions may well be conserved.
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Affiliation(s)
- Francesco Colucci
- Unit of Cytokines and Lymphoid Development, The Pasteur Institute, Paris, France.
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654
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Abstract
An array of inhibitory and activating receptors initially identified on NK cells are also expressed by conventional CD8+ alphabeta T cells. New evidence strongly implicates these 'NK cell receptors' in modulating NK cell and virus-specific CD8+ T cell responses against a variety of viral infections. Precise regulation of NK cell and T cell responses by these receptors optimizes antiviral immunity while preventing immunological bystander pathology and autoimmunity.
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Affiliation(s)
- Janice M Moser
- Department of Pathology, Woodruff Memorial Research Building, Emory University School of Medicine, 1639 Pierce Drive, Atlanta, GA 30322, USA
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655
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Abstract
Influenza virus remains a major public heath concern, both in its annual toll in death and debilitation and its potential to cause devastating pandemics. A number of recent surprising discoveries emphasize how little we know about influenza virus and its interaction with its hosts. These include the description of a novel viral protein encoded by an overlapping reading frame, the demonstration that the most abundant viral non-structural protein interferes with the induction of interferons by infected cells, and the finding that natural killer cells express activating receptors that detect viral cell-surface proteins. The introduction of improved methods for genetically manipulating influenza virus promises to revolutionize our understanding of viral replication and its interaction with the host innate and acquired immune systems, and will also enable the improvement of vaccines. Using knowledge of viral sequences recovered from archived or interred tissues from victims of the 1918 influenza pandemic, it is now possible to investigate why this virus was so pathogenic - it killed more than 20000000 people, most of whom were young adults in the prime of their lives.
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Affiliation(s)
- Jonathan Yewdell
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Room 211, Building 4, 4 Center Drive, Bethesda, Maryland 20892-0440, USA.
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656
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Lewis BJ, Croker S, Newton DJ, Lennon GP, Johnson PM, Christmas SE. Natural killer cell receptor expression by human first trimester decidual granular leukocytes and T-lymphocytes. Am J Reprod Immunol 2002; 48:103-9. [PMID: 12389599 DOI: 10.1034/j.1600-0897.2002.01115.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PROBLEM Detailed analysis of the expression of natural killer (NK) cell activatory and inhibitory receptors by human decidual leukocyte subpopulations has not been undertaken. METHOD OF STUDY Expression of the natural cytotoxicity receptors NKp30, NKp44 and NKp46 by decidual leukocytes were studied by reverse transcriptase polymerase chain reaction. Expression of the killer cell Ig-like receptors CD158a and CD158b on decidual T cells were studied by flow cytometry. RESULTS First trimester decidual leukocytes expressed mRNA for the NKp30 and NKp46 receptors but expression of NKp44, a marker of activated NK cells, was not detected. A mean of 11.8 and 15.8% of decidual T cells expressed CD158a or 158b, respectively, while only around 1% of peripheral blood T cells were CD158a+ or CD158b+. CONCLUSIONS Like peripheral blood NK cells, decidual NK cells express the natural cytotoxicity receptors NKp30 and NKp46 but the significance of this will not become apparent until ligands for these molecules have been identified. Only a minority of decidual T cells express CD158, indicating that this is not a mechanism for inhibition of cytotoxicity mediated by all decidual T cells.
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Affiliation(s)
- Barry J Lewis
- Department of Immunology, University of Liverpool, UK
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657
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Terrazzano G, Zanzi D, Palomba C, Carbone E, Grimaldi S, Pisanti S, Fontana S, Zappacosta S, Ruggiero G. Differential involvement of CD40, CD80, and major histocompatibility complex class I molecules in cytotoxicity induction and interferon‐γ production by human natural killer effectors. J Leukoc Biol 2002. [DOI: 10.1189/jlb.72.2.305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Giuseppe Terrazzano
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Delia Zanzi
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Carmen Palomba
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Ennio Carbone
- Dipartimento di Medicina Sperimentale e Clinica, Università “Magna Grecia” Catanzaro, Italy
- Microbiology and Tumorbiology Centre, Karolinska Institutet, Stockholm, Sweden; and
| | - Serena Grimaldi
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Simona Pisanti
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Silvia Fontana
- Centro di Endocrinologia e Oncologia Sperimentale, CEOS, C.N.R., Naples, Italy
| | - Serafino Zappacosta
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | - Giuseppina Ruggiero
- Cattedra di Immunologia, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
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658
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Drukker M, Katz G, Urbach A, Schuldiner M, Markel G, Itskovitz-Eldor J, Reubinoff B, Mandelboim O, Benvenisty N. Characterization of the expression of MHC proteins in human embryonic stem cells. Proc Natl Acad Sci U S A 2002; 99:9864-9. [PMID: 12114532 PMCID: PMC125045 DOI: 10.1073/pnas.142298299] [Citation(s) in RCA: 437] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Human embryonic stem (ES) cells are pluripotent cells that may be used in transplantation medicine. These cells can be induced to differentiate into cells from the three embryonic germ layers both in vivo and in vitro. To determine whether human ES cells might be rejected after transplantation, we examined cell surface expression of the MHC proteins in these cells. Our results show very low expression levels of MHC class I (MHC-I) proteins on the surface of human ES cells that moderately increase on in vitro or in vivo differentiation. A dramatic induction of MHC-I proteins was observed when the cells were treated with IFN-gamma but not with IFN-alpha or -beta. However, all three IFNs induced expression of MHC-I proteins in differentiated human ES cells. MHC-II proteins and HLA-G were not expressed on the surface of undifferentiated or differentiated cells. Ligands for natural killer cell receptors were either absent or expressed in very low levels in human ES cells and in their differentiated derivatives. In accordance, natural killer cytotoxic assays demonstrated only limited lysis of both undifferentiated and differentiated cells. To initiate a histocompatibility databank of human ES cells, we have isotyped several of the published ES cell lines for their human leukocyte antigens. In conclusion, our results demonstrate that human ES cells can express high levels of MHC-I proteins and thus may be rejected on transplantation.
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Affiliation(s)
- Micha Drukker
- Department of Genetics, Silberman Institute of Life Sciences, Hebrew University, 91904 Jerusalem, Israel
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659
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Menier C, Riteau B, Carosella ED, Rouas-Freiss N. MICA triggering signal for NK cell tumor lysis is counteracted by HLA-G1-mediated inhibitory signal. Int J Cancer 2002; 100:63-70. [PMID: 12115588 DOI: 10.1002/ijc.10460] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
MICA, a highly glycosylated membrane-anchored cell-surface MHC Class I-related chain, has recently been reported to activate NK cell cytolytic responses in epithelial tumors. Tumor cells may escape from NK lysis by counteracting NK cytotoxicity activating signals with inhibitory ones. Among the molecules that mediate an NK inhibitory signal, HLA-G1, a non-classical MHC Class I antigen, is of particular interest. HLA-G1 is ectopically expressed in various tumors, including melanoma and constitutes the major NK inhibitory ligand in the M8 melanoma cell line when coexpressed with HLA-A, -B, -C and -E molecules. We have evaluated the balance between 2 powerful signals that affect NK cell tumor lysis, one inhibitory and the other one activating, respectively HLA-G1 and MICA. For this purpose, we transfected the M8 melanoma cell line, which spontaneously expresses MICA, with HLA-G1 cDNA, using it as a target for the NKL effector. We carried out cytotoxicity assays, using antibodies that disrupt interactions between the MICA and HLA-G1 ligands and their respective NK effector counterparts, the NKG2D activating and ILT2 inhibitory receptors. Results showed that 1) MICA expressed in the M8 melanoma cell line triggered NK cell tumor lysis and 2) HLA-G1 coexpression mediated the inhibition of NK cytotoxicity by mitigating the MICA activating signal. HLA-G1 expression in a tumor cell line in which MICA is switched on would therefore appear to be a powerful way to turn off NK cells, supporting the emerging idea that the balance between positive and negative NK cytolysis signals critically influences tumor progression.
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Affiliation(s)
- Catherine Menier
- Service de Recherche en Hémato-Immunologie, Direction des Sciences du Vivant, Département de Recherche Médicale, Commissariat à l'Energie Atomique, Institut Universitaire d'Hématologie, Hôpital Saint Louis, Paris, France
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660
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Deignan T, Curry MP, Doherty DG, Golden-Mason L, Volkov Y, Norris S, Nolan N, Traynor O, McEntee G, Hegarty JE, O'Farrelly C. Decrease in hepatic CD56(+) T cells and V alpha 24(+) natural killer T cells in chronic hepatitis C viral infection. J Hepatol 2002; 37:101-8. [PMID: 12076868 DOI: 10.1016/s0168-8278(02)00072-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND/AIMS The intrahepatic immune system is likely to play a key role in determining the outcome of hepatitis C virus (HCV) infection. The hepatic lymphocyte repertoire is characterised by high CD8/CD4 T cell ratios and large numbers of gamma delta T cells, natural killer (NK) cells, NK T cells and NK receptor-positive T cells. It is not known which of these populations contribute to immunity against HCV or immune pathology. METHODS To explore the relative contributions of lymphocyte subpopulations, we have compared the intrahepatic lymphocyte repertoires and cytokine expression in 13 patients with mild chronic hepatitis C infection, 14 with end-stage hepatitis C cirrhosis and five histologically normal livers by flow cytometry and immunohistochemistry. RESULTS CD4(+) T cells bearing alpha beta T cell receptors (TCR) were significantly expanded in livers with chronic HCV infection while CD56(+) alpha beta T cells and V alpha 24 TCR-positive T cells were significantly depleted. Expanded CD4(+)T cells were predominantly Th1 cells, producing interferon-gamma but not interleukin-4. CONCLUSIONS Failure to resolve HCV infection may be due to deficient innate and/or memory immune responses, while Th1 cells may mediate immune pathology.
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Affiliation(s)
- Tina Deignan
- Education and Research Centre, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland
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661
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Natarajan K, Dimasi N, Wang J, Mariuzza RA, Margulies DH. Structure and function of natural killer cell receptors: multiple molecular solutions to self, nonself discrimination. Annu Rev Immunol 2002; 20:853-85. [PMID: 11861620 DOI: 10.1146/annurev.immunol.20.100301.064812] [Citation(s) in RCA: 235] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In contrast to T cell receptors, signal transducing cell surface membrane molecules involved in the regulation of responses by cells of the innate immune system employ structures that are encoded in the genome rather than generated by somatic recombination and that recognize either classical MHC-I molecules or their structural relatives (such as MICA, RAE-1, or H-60). Considerable progress has recently been made in our understanding of molecular recognition by such molecules based on the determination of their three-dimensional structure, either in isolation or in complex with their MHC-I ligands. Those best studied are the receptors that are expressed on natural killer (NK) cells, but others are found on populations of T cells and other hematopoietic cells. These molecules fall into two major structural classes, those of the immunoglobulin superfamily (KIRs and LIRs) and of the C-type lectin-like family (Ly49, NKG2D, and CD94/NKG2). Here we summarize, in a functional context, the structures of the murine and human molecules that have recently been determined, with emphasis on how they bind different regions of their MHC-I ligands, and how this allows the discrimination of tumor or virus-infected cells from normal cells of the host.
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MESH Headings
- Alleles
- Amino Acid Sequence
- Animals
- Antigens, CD/chemistry
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Antigens, Ly
- Histocompatibility Antigens Class I/chemistry
- Histocompatibility Antigens Class I/metabolism
- Humans
- Killer Cells, Natural/immunology
- Lectins, C-Type
- Leukocyte Immunoglobulin-like Receptor B1
- Macromolecular Substances
- Membrane Glycoproteins/chemistry
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Models, Molecular
- Molecular Sequence Data
- Molecular Structure
- NK Cell Lectin-Like Receptor Subfamily D
- Receptors, Immunologic/chemistry
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- Receptors, KIR
- Receptors, KIR2DL1
- Receptors, NK Cell Lectin-Like
- Self Tolerance
- Sequence Homology, Amino Acid
- Signal Transduction
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Affiliation(s)
- Kannan Natarajan
- Molecular Biology Section, Laboratory of Immunology, NIAID, NIH, Bethesda, Maryland 20892-1892, USA.
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662
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Zeng J, Fournier P, Schirrmacher V. Induction of interferon-alpha and tumor necrosis factor-related apoptosis-inducing ligand in human blood mononuclear cells by hemagglutinin-neuraminidase but not F protein of Newcastle disease virus. Virology 2002; 297:19-30. [PMID: 12083832 DOI: 10.1006/viro.2002.1413] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To determine molecular viral components which can induce innate immune responses in human peripheral blood mononuclear cells (PBMC), we investigated the anti-neoplastic agent Newcastle disease virus (NDV) and its two spike proteins hemagglutinin-neuraminidase (HN) and fusion protein (F). NDV was an excellent inducer in PBMC of IFN-alpha production and capable of inducing upregulation of plasma membrane expression of tumor necrosis factor related apoptosis inducing ligand (TRAIL). Viral replication was not required for these responses because NDV inactivated for 5 min by UV was as good as live NDV. NDV-modified and paraformaldehyde-fixed BHK cells could also trigger IFN-alpha and TRAIL induction, indicating that contacts of responder cells with NDV-modified cell surfaces are sufficient to induce these activities in PBMC. Antibodies against HN but not F were able to block these responses. Finally we could show that HN but not F induced IFN-alpha and TRAIL in PBMC. This was possible through the use of respective gene transfectants generated with the help of Semliki Forest virus (SFV) replicase-based DNA recombinant expression systems. Upon contact with BHK cells expressing HN but not F at their cell surface, human PBMC produced IFN-alpha and some cells, including monocytes and T lymphocytes, upregulated cell surface TRAIL expression.
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Affiliation(s)
- Jinyang Zeng
- German Cancer Research Center, Division of Cellular Immunology, 69120 Heidelberg, Germany
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663
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Jiang K, Zhong B, Gilvary DL, Corliss BC, Vivier E, Hong-Geller E, Wei S, Djeu JY. Syk regulation of phosphoinositide 3-kinase-dependent NK cell function. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:3155-64. [PMID: 11907067 DOI: 10.4049/jimmunol.168.7.3155] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Emerging evidence suggests that NK-activatory receptors use KARAP/DAP12, CD3zeta, and FcepsilonRIgamma adaptors that contain immunoreceptor tyrosine-based activatory motifs to mediate NK direct lysis of tumor cells via Syk tyrosine kinase. NK cells may also use DAP10 to drive natural cytotoxicity through phosphoinositide 3-kinase (PI3K). In contrast to our recently identified PI3K pathway controlling NK cytotoxicity, the signaling mechanism by which Syk associates with downstream effectors to drive NK lytic function has not been clearly defined. In NK92 cells, which express DAP12 but little DAP10/NKG2D, we now show that Syk acts upstream of PI3K, subsequently leading to the specific signaling of the PI3K-->Rac1-->PAK1-->mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase-->ERK cascade that we earlier described. Tumor cell ligation stimulated DAP12 tyrosine phosphorylation and its association with Syk in NK92 cells; Syk tyrosine phosphorylation and activation were also observed. Inhibition of Syk function by kinase-deficient Syk or piceatannol blocked target cell-induced PI3K, Rac1, PAK1, mitogen-activated protein/ERK kinase, and ERK activation, perforin movement, as well as NK cytotoxicity, indicating that Syk is upstream of all these signaling events. Confirming that Syk does not act downstream of PI3K, constitutively active PI3K reactivated all the downstream effectors as well as NK cytotoxicity suppressed in Syk-impaired NK cells. Our results are the first report documenting the instrumental role of Syk in control of PI3K-dependent natural cytotoxicity.
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Affiliation(s)
- Kun Jiang
- Immunology Program, H. Lee Moffitt Cancer Center, Department of Interdisciplinary Oncology, University of South Florida College of Medicine, Tampa, FL 33612, USA
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664
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Vankayalapati R, Wizel B, Weis SE, Safi H, Lakey DL, Mandelboim O, Samten B, Porgador A, Barnes PF. The NKp46 receptor contributes to NK cell lysis of mononuclear phagocytes infected with an intracellular bacterium. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:3451-7. [PMID: 11907104 DOI: 10.4049/jimmunol.168.7.3451] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We used human tuberculosis as a model to investigate the role of NK cytotoxic mechanisms in the immune response to intracellular infection. Freshly isolated NK cells and NK cell lines from healthy donors lysed Mycobacterium tuberculosis-infected monocytes to a greater extent than uninfected monocytes. Lysis of infected monocytes was associated with increased expression of mRNA for the NKp46 receptor, but not the NKp44 receptor. Antisera to NKp46 markedly inhibited lysis of infected monocytes. NK cell-mediated lysis was not due to reduced expression of MHC class I molecules on the surface of infected monocytes or to enhanced production of IL-18 or IFN-gamma. NK cell lytic activity against M. tuberculosis-infected monocytes and NKp46 mRNA expression were reduced in tuberculosis patients with ineffective immunity to M. tuberculosis compared with findings in healthy donors. These observations suggest that 1) the NKp46 receptor participates in NK cell-mediated lysis of cells infected with an intracellular pathogen, and 2) the reduced functional capacity of NK cells is associated with severe manifestations of infectious disease.
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MESH Headings
- Cell Line
- Cell Survival/immunology
- Cells, Cultured
- Coculture Techniques
- Cytokines/biosynthesis
- Cytokines/immunology
- Cytotoxicity, Immunologic/immunology
- Histocompatibility Antigens Class I/biosynthesis
- Humans
- Immune Sera/pharmacology
- Intracellular Fluid/immunology
- Intracellular Fluid/microbiology
- K562 Cells
- Killer Cells, Natural/cytology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/microbiology
- Monocytes/immunology
- Monocytes/metabolism
- Monocytes/microbiology
- Mycobacterium tuberculosis/immunology
- Natural Cytotoxicity Triggering Receptor 1
- Natural Cytotoxicity Triggering Receptor 2
- Phagocytes/immunology
- Phagocytes/microbiology
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/biosynthesis
- Receptors, Immunologic/biosynthesis
- Receptors, Immunologic/genetics
- Receptors, Immunologic/immunology
- Receptors, Immunologic/physiology
- Tuberculosis/immunology
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Affiliation(s)
- Ramakrishna Vankayalapati
- Center for Pulmonary and Infectious Disease Control, University of Texas Health Center, Tyler, TX 75708, USA
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665
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Markel G, Lieberman N, Katz G, Arnon TI, Lotem M, Drize O, Blumberg RS, Bar-Haim E, Mader R, Eisenbach L, Mandelboim O. CD66a interactions between human melanoma and NK cells: a novel class I MHC-independent inhibitory mechanism of cytotoxicity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:2803-10. [PMID: 11884449 DOI: 10.4049/jimmunol.168.6.2803] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NK cells are able to kill virus-infected and tumor cells via a panel of lysis receptors. Cells expressing class I MHC proteins are protected from lysis primarily due to the interactions of several families of NK receptors with both classical and nonclassical class I MHC proteins. In this study we show that a class I MHC-deficient melanoma cell line (1106mel) is stained with several Ig-fused lysis receptors, suggesting the expression of the appropriate lysis ligands. Surprisingly, however, this melanoma line was not killed by CD16-negative NK clones. The lack of killing is shown to be the result of homotypic CD66a interactions between the melanoma line and the NK cells. Furthermore, 721.221 cells expressing the CD66a protein were protected from lysis by YTS cells and by NK cells expressing the CD66a protein. Redirected lysis experiments demonstrated that the strength of the inhibitory effect is correlated with the levels of CD66a expression. Finally, the expression of CD66a protein was observed on NK cells derived from patients with malignant melanoma. These findings suggest the existence of a novel class I MHC-independent inhibitory mechanism of human NK cell cytotoxicity. This may be a mechanism that is used by some of the class I MHC-negative melanoma cells to evade attack by CD66a-positive NK cells.
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MESH Headings
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, CD/metabolism
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/genetics
- Antigens, Differentiation/immunology
- Antigens, Differentiation/metabolism
- Cell Adhesion Molecules
- Cells, Cultured
- Cytotoxicity Tests, Immunologic
- Cytotoxicity, Immunologic/immunology
- Histocompatibility Antigens Class I/biosynthesis
- Histocompatibility Antigens Class I/genetics
- Histocompatibility Antigens Class I/metabolism
- Humans
- Immunosuppression Therapy
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Ligands
- Melanoma/genetics
- Melanoma/immunology
- Melanoma/metabolism
- Receptors, IgG/biosynthesis
- Receptors, IgG/deficiency
- Receptors, IgG/genetics
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- Gal Markel
- Lautenberg Center for General and Tumor Immunology and Sharet Institute of Oncology, Hadassah Medical School, Jerusalem, Israel
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666
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Borrego F, Kabat J, Kim DK, Lieto L, Maasho K, Peña J, Solana R, Coligan JE. Structure and function of major histocompatibility complex (MHC) class I specific receptors expressed on human natural killer (NK) cells. Mol Immunol 2002; 38:637-60. [PMID: 11858820 DOI: 10.1016/s0161-5890(01)00107-9] [Citation(s) in RCA: 205] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Natural killer (NK) cells express receptors that are specific for MHC class I molecules. These receptors play a crucial role in regulating the lytic and cytokine expression capabilities of NK cells. In humans, three distinct families of genes have been defined that encode for receptors of HLA class I molecules. The first family identified consists of type I transmembrane molecules belonging to the immunoglobulin (Ig) superfamily and are called killer cell Ig-like receptors (KIR). A second group of receptors belonging to the Ig superfamily, named ILT (for immunoglobulin like transcripts), has more recently been described. ILTs are expressed mainly on B, T and myeloid cells, but some members of this group are also expressed on NK cells. They are also referred to as LIRs (for leukocyte Ig-like receptor) and MIRs (for macrophage Ig-like receptor). The ligands for the KIR and some of the ILT receptors include classical (class Ia) HLA class I molecules, as well as the nonclassical (class Ib) HLA-G molecule. The third family of HLA class I receptors are C-type lectin family members and are composed of heterodimers of CD94 covalently associated with a member of the NKG2 family of molecules. The ligand for most members is the nonclassical class I molecule HLA-E. NKG2D, a member of the NKG2 family, is expressed as a homodimer, along with the adaptor molecule DAP10. The ligands of NKG2D include the human class I like molecules MICA and MICB, and the recently described ULBPs. Each of these three families of receptors has individual members that can recognize identical or similar ligands yet signal for activation or inhibition of cellular functions. This dichotomy correlates with particular structural features present in the transmembrane and intracytoplasmic portions of these molecules. In this review we will discuss the molecular structure, specificity, cellular expression patterns, and function of these HLA class I receptors, as well as the chromosomal location and genetic organization.
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Affiliation(s)
- Francisco Borrego
- Receptor Cell Biology Section, Laboratory of Allergic Diseases, NIAID, NIH, Twinbrook II, Room 205, 12441 Parklawn Dr., Rockville, MD 20852, USA
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667
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Poggi A, Carosio R, Spaggiari GM, Fortis C, Tambussi G, Dell'Antonio G, Dal Cin E, Rubartelli A, Zocchi MR. NK cell activation by dendritic cells is dependent on LFA-1-mediated induction of calcium-calmodulin kinase II: inhibition by HIV-1 Tat C-terminal domain. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:95-101. [PMID: 11751951 DOI: 10.4049/jimmunol.168.1.95] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this study, we show that binding to autologous dendritic cells (DC) induces a calcium influx in NK cells, followed by activation of the calcium-calmodulin kinase II (CAMKII), release of perforin and granzymes, and IFN-gamma secretion. CAMKII is induced via LFA-1: indeed, oligomerization of LFA-1 leads to CAMKII induction in NK cells. Moreover, release of lytic enzymes and cytotoxic activity is strongly reduced by masking LFA-1 or by adding CAMKII inhibitors such as KN62 and KN93, at variance with the inactive compound KN92. NK cell-mediated lysis of DC and IFN-gamma release by NK cells upon NK/DC contact are inhibited by exogenous HIV-1 Tat: the protein blocks calcium influx and impairs CAMKII activation elicited via LFA-1 in NK cells, eventually inhibiting degranulation. Experiments performed with synthetic, overlapping Tat-derived peptides showed that the C-terminal domain of the protein is responsible for inhibition. Finally, both KN62 and Tat reduced the extension of NK/DC contacts, possibly affecting NK cell granule polarization toward the target. These data provide evidence that exogenous Tat inhibits NK cell activation occurring upon contact with DC: this mechanism might contribute to the impairment of natural immunity in HIV-1 infection.
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MESH Headings
- Calcium Signaling
- Calcium-Calmodulin-Dependent Protein Kinase Type 2
- Calcium-Calmodulin-Dependent Protein Kinases/metabolism
- Cell Degranulation
- Cells, Cultured
- Cytotoxicity Tests, Immunologic
- Cytotoxicity, Immunologic
- Dendritic Cells/immunology
- Dendritic Cells/ultrastructure
- Enzyme Activation
- Gene Products, tat/chemistry
- Gene Products, tat/pharmacology
- HIV-1
- Humans
- Interferon-gamma/biosynthesis
- Killer Cells, Natural/drug effects
- Killer Cells, Natural/immunology
- Killer Cells, Natural/ultrastructure
- Lymphocyte Activation
- Lymphocyte Function-Associated Antigen-1/physiology
- Membrane Glycoproteins/metabolism
- Perforin
- Pore Forming Cytotoxic Proteins
- Protein Structure, Tertiary
- Serine Endopeptidases/metabolism
- Tumor Cells, Cultured
- tat Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- Alessandro Poggi
- Laboratory of Immunology, National Institute for Cancer Research, Genoa, Italy
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668
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MESH Headings
- Animals
- Bone Marrow Transplantation
- Cytotoxicity, Immunologic
- Evolution, Molecular
- Forecasting
- Histocompatibility Antigens Class I/immunology
- Humans
- Immunologic Surveillance
- Immunotherapy, Adoptive
- Killer Cells, Natural/classification
- Killer Cells, Natural/cytology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/transplantation
- Lymphocyte Activation/physiology
- Neoplasms/immunology
- Pan troglodytes/immunology
- Receptors, Immunologic/genetics
- Receptors, Immunologic/immunology
- Receptors, KIR
- Rodentia/immunology
- Virus Diseases/immunology
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Affiliation(s)
- Alessandro Moretta
- Dipartimento di Medicina Sperimentale, Università degli Studi di Genova, Genova, Italy
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669
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Boon ACM, de Mutsert G, Graus YMF, Fouchier RAM, Sintnicolaas K, Osterhaus ADME, Rimmelzwaan GF. The magnitude and specificity of influenza A virus-specific cytotoxic T-lymphocyte responses in humans is related to HLA-A and -B phenotype. J Virol 2002; 76:582-90. [PMID: 11752149 PMCID: PMC136822 DOI: 10.1128/jvi.76.2.582-590.2002] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The repertoire of human cytotoxic T-lymphocytes (CTL) in response to influenza A viruses has been shown to be directed towards multiple epitopes, with a dominant response to the HLA-A2-restricted M1(58-66) epitope. These studies, however, were performed with peripheral blood mononuclear cells (PBMC) of individuals selected randomly with respect to HLA phenotype or selected for the expression of one HLA allele without considering an influence of other HLA molecules. In addition, little information is available on the influence of HLA makeup on the overall CTL response against influenza viruses. Here, the influenza A virus-specific CTL response was investigated in groups of HLA-A and -B identical individuals. Between groups the individuals shared two or three of the four HLA-A and -B alleles. After in vitro stimulation of PBMC with influenza virus, the highest CTL activity was found in HLA-A2(+) donors. A similar pattern was observed for the precursor frequency of virus-specific CTL (CTLp) ex vivo, with a higher CTLp frequency in HLA-A2-positive donors than in HLA-A2-negative donors, which were unable to recognize the immunodominant M1(58-66) epitope. In addition, CTL activity and frequency of CTLp for the individual influenza virus epitopes were determined. The frequency of CTLp specific for the HLA-B8-restricted epitope NP(380-388) was threefold lower in HLA-B27-positive donors than in HLA-B27-negative donors. In addition, the frequency of CTLp specific for the HLA-A1-restricted epitope NP(44-52) was threefold higher in HLA-A1-, -A2-, -B8-, and -B35-positive donors than in other donors, which was confirmed by measuring the CTL activity in vitro. These findings indicate that the epitope specificity of the CTL response is related to the phenotype of the other HLA molecules. Furthermore, the magnitude of the influenza virus-specific CTL response seems dependent on the HLA-A and -B phenotypes.
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Affiliation(s)
- A C M Boon
- Institute of Virology, Erasmus University Rotterdam, 3015 GE Rotterdam, The Netherlands
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670
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Fassett MS, Davis DM, Valter MM, Cohen GB, Strominger JL. Signaling at the inhibitory natural killer cell immune synapse regulates lipid raft polarization but not class I MHC clustering. Proc Natl Acad Sci U S A 2001; 98:14547-52. [PMID: 11724921 PMCID: PMC64719 DOI: 10.1073/pnas.211563598] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2001] [Indexed: 12/23/2022] Open
Abstract
Natural killer (NK) cell cytotoxicity is determined by a balance of positive and negative signals. Negative signals are transmitted by NK inhibitory receptors (killer immunoglobulin-like receptors, KIR) at the site of membrane apposition between an NK cell and a target cell, where inhibitory receptors become clustered with class I MHC ligands in an organized structure known as an inhibitory NK immune synapse. Immune synapse formation in NK cells is poorly understood. Because signaling by NK inhibitory receptors could be involved in this process, the human NK tumor line YTS was transfected with signal-competent and signal-incompetent KIR2DL1. The latter were generated by truncating the KIR2DL1 cytoplasmic tail or by introducing mutations in the immunoreceptor tyrosine-based inhibition motifs. The KIR2DL1 mutants retained their ability to cluster class I MHC ligands on NK cell interaction with appropriate target cells. Therefore, receptor-ligand clustering at the inhibitory NK immune synapse occurs independently of KIR2DL1 signal transduction. However, parallel examination of NK cell membrane lipid rafts revealed that KIR2DL1 signaling is critical for blocking lipid raft polarization and NK cell cytotoxicity. Moreover, raft polarization was inhibited by reagents that disrupt microtubules and actin filaments, whereas synapse formation was not. Thus, NK lipid raft polarization and inhibitory NK immune synapse formation occur by fundamentally distinct mechanisms.
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Affiliation(s)
- M S Fassett
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
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671
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Chen W, Calvo PA, Malide D, Gibbs J, Schubert U, Bacik I, Basta S, O'Neill R, Schickli J, Palese P, Henklein P, Bennink JR, Yewdell JW. A novel influenza A virus mitochondrial protein that induces cell death. Nat Med 2001; 7:1306-12. [PMID: 11726970 DOI: 10.1038/nm1201-1306] [Citation(s) in RCA: 731] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
While searching for alternative reading-frame peptides encoded by influenza A virus that are recognized by CD8+ T cells, we found an abundant immunogenic peptide encoded by the +1 reading frame of PB1. This peptide derives from a novel conserved 87-residue protein, PB1-F2, which has several unusual features compared with other influenza gene products in addition to its mode of translation. These include its absence from some animal (particularly swine) influenza virus isolates, variable expression in individual infected cells, rapid proteasome-dependent degradation and mitochondrial localization. Exposure of cells to a synthetic version of PB1-F2 induces apoptosis, and influenza viruses with targeted mutations that interfere with PB1-F2 expression induce less extensive apoptosis in human monocytic cells than those with intact PB1-F2. We propose that PB1-F2 functions to kill host immune cells responding to influenza virus infection.
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Affiliation(s)
- W Chen
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA
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672
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Carlin LM, Eleme K, McCann FE, Davis DM. Intercellular transfer and supramolecular organization of human leukocyte antigen C at inhibitory natural killer cell immune synapses. J Exp Med 2001; 194:1507-17. [PMID: 11714757 PMCID: PMC2193674 DOI: 10.1084/jem.194.10.1507] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
After accumulation of target cell human leukocyte antigen (HLA)-C at inhibitory natural killer (NK) cell immune synapses, some HLA-C transfers from target cells to NK cell plasma membranes and cytoplasm. This unexpected intercellular transfer of HLA-C is dependent on NK receptor recognition, since HLA-Cw6 or -Cw4 but not -Cw3 transfer to an NK transfectant expressing killer Ig-like receptor (KIR)2DL1. Strikingly, live-cell time-lapse laser scanning confocal microscopy shows vesicles containing target cell green fluorescent protein-tagged HLA-C migrating away from immune synapses into NK cells. Unlike clustering of HLA-C at the immune synapse, intercellular transfer of HLA-C is dependent on NK cell ATP, but not target cell ATP. However, the intercellular transfer of HLA-C is not dependent on active polymerization of the actin cytoskeleton. In addition, different arrangements of HLA-C are seen at inhibitory NK immune synapses, and these alter as NK synapses mature, but in a fashion distinct from that seen upon T cell activation.
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Affiliation(s)
- L M Carlin
- Department of Biological Sciences, Sir Alexander Fleming Building, Imperial College of Science, Technology, and Medicine, South Kensington, London SW7 2AZ, United Kingdom
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673
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Abstract
Natural killer cells are innate immune cells that control certain microbial infections and tumours. The function of natural killer cells is regulated by a balance between signals transmitted by activating receptors, which recognize ligands on tumours and virus-infected cells, and inhibitory receptors specific for major histocompatibility complex class I molecules. Here, we review the emerging evidence that natural killer cells have an important role in vivo in immune defence.
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Affiliation(s)
- A Cerwenka
- Department of Microbiology and Immunology and the Cancer Research Institute, University of California, San Francisco, 94143-0414, USA
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674
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Magor BG, Magor KE. Evolution of effectors and receptors of innate immunity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2001; 25:651-682. [PMID: 11602189 DOI: 10.1016/s0145-305x(01)00029-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The bony fishes are derived from one of the earliest divergent vertebrate lineages to have both innate and acquired immune systems. They are considered by some to be an ideal model to study the underpinnings of immune systems precisely because of their phylogenetic position and the fact that their adaptive immune systems have not been elaborated to the extent seen in mammals. By the same token, examination of innate immune systems in invertebrates and early chordates can provide insight into how homologous systems operate in fish and higher vertebrates. Herein, we provide an overview of the molecular evidence that we hope helps clarify the evolutionary relationships of innate immune molecules identified in bony fishes. The innate immune systems being considered include select chemokines (CC and CXC chemokines and their receptors), cytokines (IL-1, IL-8, interferons, TGF-beta, TNF-alpha), acute phase proteins (SAA, SAP, CRP, alpha2M, and the complement components--C3-C9, MASP, MBL, Bf), NK cell receptors, and molecules upstream and downstream of the Toll signaling pathways.
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Affiliation(s)
- B G Magor
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E5, Canada.
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675
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Abstract
Natural killer (NK) cells destroy virus-infected and tumor cells without prior antigen stimulation. The NK cell cytotoxicity is regulated in large part by the expression of NK cell receptors that are able to bind major histocompatibility complex (MHC) class I glycoproteins. NK cells also express lysis triggering receptors specific for non-MHC ligands, including NKp30, NKp44, NKp46 and CD16. However, the nature of their ligands, recognized on target cells, is undefined. We have recently shown that the NKp46 protein, but not the CD16 protein, recognizes the hemagglutinin (HA) of influenza virus (IV) and the hemagglutinin-neuraminidase (HN) of Sendai virus (SV), and that the recognition of HA from IV requires the sialylation of NKp46 oligosaccharides. We have also demonstrated that binding of NKp46 to HA of IV is required for lysis of cells expressing the corresponding glycoproteins by a substantial subset of NK clones. Here we show that NKp44, but not NKp30, can also recognize the HA of both IV and SV and that the recognition of IV HA requires the sialylation of the NKp44 receptor in a similar way to that of NKp46. SV infection of 721.221 cells expressing MHC class I proteinsresulted in the abrogation of the inhibition by NK clones expressing high levels of NKp44. In addition, the binding of NKp44 to HA improves the ability of some NK clones to lyse IV infected cells.
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Affiliation(s)
- T I Arnon
- The Lautenberg Center for General and Tumor Immunology, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
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676
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Abstract
HLA class I and NK receptors are encoded within dense clusters of immune loci. The MHC, at 6p21.3, and the complex containing the KIR loci, at 19q13.4, both feature variation in the number of genes, as well as sequence polymorphism. In addition to T cell receptors, several variable class I-related molecules interact with polymorphic NK receptors. Some of the lectin-related NK receptor genes, at 12p13.1, also have ligands belonging to the extended class I family. The expanding clusters of class I-related sequences and their receptors, some of which evolved recently, reveal further complexity in immune recognition of disease.
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Affiliation(s)
- J Trowsdale
- Immunology Division, Pathology Department, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, United Kingdom
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677
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Chiorean EG, Miller JS. The biology of natural killer cells and implications for therapy of human disease. JOURNAL OF HEMATOTHERAPY & STEM CELL RESEARCH 2001; 10:451-63. [PMID: 11522229 DOI: 10.1089/15258160152509073] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Natural killer (NK) cells are unique lymphocytes capable of lysing target cells without prior immunization. NK cells activated with cytokines, like interleukin-2 (IL-2), have been used since the 1980s as adoptive immunotherapy against metastatic solid tumors, but their effectiveness has been limited. The mechanisms by which NK cells recognize their targets are complex, including newly identified receptors that recognize class I MHC molecules. Understanding these mechanisms may support the use of NK cells as clinical therapy against infectious diseases and cancer. We have been interested in the use of NK cells clinically for their potential to eradicate minimal residual disease and prevent relapses after autologous stem cell transplantation. Several strategies are discussed to increase the specificity and efficacy of NK cell therapy. One method is to increase the targeting of NK cells by the use of monoclonal antibodies. Another approach uses allogeneic NK cells to overcome the inhibitory receptor mechanisms that may block target cell lysis by recognition of class I molecules. These and other novel strategies may prove to be attractive and effective immunotherapeutic tools to manipulate NK cells to fight human disease.
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Affiliation(s)
- E G Chiorean
- Department of Medicine, Division of Hematology, Oncology and Transplantation, University of Minnesota Cancer Center, Minneapolis, MN 55455, USA
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678
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679
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Biassoni R, Cantoni C, Falco M, Pende D, Millo R, Moretta L, Bottino C, Moretta A. Human natural killer cell activating receptors. Mol Immunol 2000; 37:1015-24. [PMID: 11399319 DOI: 10.1016/s0161-5890(01)00018-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Natural killer (NK) cells were poorly characterized until 10 years ago and few molecules expressed on their cell surface were known. Now the situation has changed dramatically, since a plethora of receptors characterized by opposite functions have been functionally and molecularly defined. NK cells express clonally distributed inhibitory receptors specific for different groups of HLA class I alleles, thus protecting normal cells from NK-mediated lysis. On the contrary, various activating receptors are involved in triggering of NK-mediated natural cytotoxicity. Their engagement induces human NK cells to kill target cells that are either HLA class I-negative or -deficient. Here a brief description of the activating receptors and coreceptor and of their ligand(s) is given.
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Affiliation(s)
- R Biassoni
- Istituto Nazionale per la Ricerca sul Cancro, Laboratorio di Immunologia, IST/CBA, L.go R. Benzi, 10, 16132, Genova, Italy.
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