1
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Tano-Menka R, Singh NK, Muzhingi I, Li X, Mandanas MV, Kaseke C, Crain CR, Zhang A, Ogunshola FJ, Vecchiarello L, Piechocka-Trocha A, Bashirova A, Birnbaum ME, Carrington M, Walker BD, Gaiha GD. Polymorphic residues in HLA-B that mediate HIV control distinctly modulate peptide interactions with both TCR and KIR molecules. Structure 2024; 32:1121-1136.e5. [PMID: 38733995 PMCID: PMC11329236 DOI: 10.1016/j.str.2024.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/27/2024] [Accepted: 04/16/2024] [Indexed: 05/13/2024]
Abstract
Immunogenetic studies have shown that specific HLA-B residues (67, 70, 97, and 156) mediate the impact of HLA class I on HIV infection, but the molecular basis is not well understood. Here we evaluate the function of these residues within the protective HLA-B∗5701 allele. While mutation of Met67, Ser70, and Leu156 disrupt CD8+ T cell recognition, substitution of Val97 had no significant impact. Thermal denaturation of HLA-B∗5701-peptide complexes revealed that Met67 and Leu156 maintain HLA-peptide stability, while Ser70 and Leu156 facilitate T cell receptor (TCR) interactions. Analyses of existing structures and structural models suggested that Val97 mediates HLA-peptide binding to inhibitory KIR3DL1 molecules, which was confirmed by experimental assays. These data thereby demonstrate that the genetic basis by which host immunity impacts HIV outcomes occurs by modulating HLA-B-peptide stability and conformation for interaction with TCR and killer immunoglobulin receptor (KIR) molecules. Moreover, they indicate a key role for epitope specificity and HLA-KIR interactions to HIV control.
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MESH Headings
- Humans
- HLA-B Antigens/chemistry
- HLA-B Antigens/metabolism
- HLA-B Antigens/genetics
- HLA-B Antigens/immunology
- Protein Binding
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/immunology
- HIV-1/immunology
- HIV-1/metabolism
- HIV Infections/immunology
- HIV Infections/virology
- Models, Molecular
- Receptors, KIR3DL1/metabolism
- Receptors, KIR3DL1/chemistry
- Receptors, KIR3DL1/genetics
- Peptides/chemistry
- Peptides/metabolism
- Binding Sites
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Polymorphism, Genetic
- Protein Stability
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Affiliation(s)
- Rhoda Tano-Menka
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Nishant K Singh
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Itai Muzhingi
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Xiaolong Li
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; The First Affiliated School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Michael V Mandanas
- Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02142, USA
| | - Clarety Kaseke
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Charles R Crain
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Angela Zhang
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Funsho J Ogunshola
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | | | - Alicja Piechocka-Trocha
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Arman Bashirova
- Basic Science Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; Laboratory of Integrative Cancer Immunology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Michael E Birnbaum
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mary Carrington
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Basic Science Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA; Laboratory of Integrative Cancer Immunology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Bruce D Walker
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Institute for Medical Engineering and Science and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Gaurav D Gaiha
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Gastroenterology, Massachusetts General Hospital, Boston, MA 02114, USA.
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2
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Piersma SJ, Li S, Wong P, Bern MD, Poursine-Laurent J, Yang L, Beckman DL, Parikh BA, Yokoyama WM. Expression of a single inhibitory Ly49 receptor is sufficient to license NK cells for effector functions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.04.597367. [PMID: 38895234 PMCID: PMC11185686 DOI: 10.1101/2024.06.04.597367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Natural killer (NK) cells recognize target cells through germline-encoded activation and inhibitory receptors enabling effective immunity against viruses and cancer. The Ly49 receptor family in the mouse and killer immunoglobin-like receptor family in humans play a central role in NK cell immunity through recognition of MHC class I and related molecules. Functionally, these receptor families are involved in licensing and rejection of MHC-I-deficient cells through missing-self. The Ly49 family is highly polymorphic, making it challenging to detail the contributions of individual Ly49 receptors to NK cell function. Herein, we showed mice lacking expression of all Ly49s were unable to reject missing-self target cells in vivo, were defective in NK cell licensing, and displayed lower KLRG1 on the surface of NK cells. Expression of Ly49A alone on a H-2Dd background restored missing-self target cell rejection, NK cell licensing, and NK cell KLRG1 expression. Thus, a single inhibitory Ly49 receptor is sufficient to license NK cells and mediate missing-self in vivo.
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Affiliation(s)
- Sytse J. Piersma
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shasha Li
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Pamela Wong
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Michael D. Bern
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jennifer Poursine-Laurent
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Liping Yang
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Diana L. Beckman
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Bijal A. Parikh
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wayne M. Yokoyama
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St. Louis, MO 63110, USA
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3
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Wickström SL, Wagner AK, Fuchs S, Elemans M, Kritikou J, Mehr R, Kärre K, Johansson MH, Brauner H. MHC Class I–Dependent Shaping of the NK Cell Ly49 Receptor Repertoire Takes Place Early during Maturation in the Bone Marrow. THE JOURNAL OF IMMUNOLOGY 2022; 209:751-759. [DOI: 10.4049/jimmunol.2100775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 05/27/2022] [Indexed: 01/04/2023]
Abstract
Abstract
MHC class I (MHC I) expression in the host influences NK cells in a process termed education. The result of this education is reflected in the responsiveness of NK cells at the level of individual cells as well as in the repertoire of inhibitory MHC I–specific receptors at the NK cell system level. The presence of MHC I molecules in the host environment gives rise to a skewed receptor repertoire in spleen NK cells where subsets expressing few (one or two) inhibitory receptors are expanded whereas subsets with many (three or more) receptors are contracted. It is not known whether this MHC I–dependent skewing is imposed during development or after maturation of NK cells. In this study, we tested the hypothesis that the NK cell receptor repertoire is shaped already early during NK cell development in the bone marrow. We used mice with a repertoire imposed by a single MHC I allele, as well as a C57BL/6 mutant strain with exaggerated repertoire skewing, to investigate Ly49 receptor repertoires at different stages of NK cell differentiation. Our results show that NK cell inhibitory receptor repertoire skewing can indeed be observed in the bone marrow, even during the earliest developmental steps where Ly49 receptors are expressed. This may partly be accounted for by selective proliferation of certain NK cell subsets, but other mechanisms must also be involved. We propose a model for how repertoire skewing is established during a developmental phase in the bone marrow, based on sequential receptor expression as well as selective proliferation.
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Affiliation(s)
- Stina L. Wickström
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- †Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Arnika K. Wagner
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- ‡Department of Medicine, Huddinge, Center for Hematology and Regenerative Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Sina Fuchs
- §Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Marjet Elemans
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- ¶Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Joanna Kritikou
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Ramit Mehr
- ‖Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel; and
| | - Klas Kärre
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Maria H. Johansson
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Hanna Brauner
- *Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- §Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
- #Dermatology Clinic, Karolinska University Hospital, Stockholm, Sweden
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4
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Millan AJ, Hom BA, Libang JB, Sindi S, Manilay JO. Evidence for Prescribed NK Cell Ly-49 Developmental Pathways in Mice. THE JOURNAL OF IMMUNOLOGY 2021; 206:1215-1227. [PMID: 33495236 DOI: 10.4049/jimmunol.2000613] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 12/30/2020] [Indexed: 12/16/2022]
Abstract
Previous studies of NK cell inhibitory Ly-49 genes showed their expression is stochastic. However, relatively few studies have examined the mechanisms governing acquisition of inhibitory receptors in conjunction with activating Ly-49 receptors and NK cell development. We hypothesized that the surface expression of activating Ly-49 receptors is nonrandom and is influenced by inhibitory Ly-49 receptors. We analyzed NK cell "clusters" defined by combinatorial expression of activating (Ly-49H and Ly-49D) and inhibitory (Ly-49I and Ly-49G2) receptors in C57BL/6 mice. Using the product rule to evaluate the interdependencies of the Ly-49 receptors, we found evidence for a tightly regulated expression at the immature NK cell stage, with the highest interdependencies between clusters that express at least one activating receptor. Further analysis demonstrated that certain NK clusters predominated at the immature (CD27+CD11b-), transitional (CD27+CD11b+), and mature (CD27-CD11b-) NK cell stages. Using parallel in vitro culture and in vivo transplantation of sorted NK clusters, we discovered nonrandom expression of Ly-49 receptors, suggesting that prescribed pathways of NK cluster differentiation exist. Our data infer that surface expression of Ly-49I is an important step in NK cell maturation. Ki-67 expression and cell counts confirmed that immature NK cells proliferate more than mature NK cells. We found that MHC class I is particularly important for regulation of Ly-49D and Ly-49G2, even though no known MHC class I ligand for these receptors is present in B6 mice. Our data indicate that surface expression of both activating and inhibitory Ly-49 receptors on NK cell clusters occurs in a nonrandom process correlated to their maturation stage.
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Affiliation(s)
- Alberto J Millan
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA 95343.,Department of Applied Mathematics, School of Natural Sciences, University of California, Merced, Merced, CA 95343; and
| | - Bryan A Hom
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA 95343
| | - Jeremy B Libang
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA 95343
| | - Suzanne Sindi
- Department of Applied Mathematics, School of Natural Sciences, University of California, Merced, Merced, CA 95343; and.,Quantitative and Systems Biology Graduate Group, School of Natural Sciences, University of California, Merced, Merced, CA 95343
| | - Jennifer O Manilay
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA 95343; .,Quantitative and Systems Biology Graduate Group, School of Natural Sciences, University of California, Merced, Merced, CA 95343
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5
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Meissl K, Simonović N, Amenitsch L, Witalisz-Siepracka A, Klein K, Lassnig C, Puga A, Vogl C, Poelzl A, Bosmann M, Dohnal A, Sexl V, Müller M, Strobl B. STAT1 Isoforms Differentially Regulate NK Cell Maturation and Anti-tumor Activity. Front Immunol 2020; 11:2189. [PMID: 33042133 PMCID: PMC7519029 DOI: 10.3389/fimmu.2020.02189] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/11/2020] [Indexed: 12/18/2022] Open
Abstract
Natural killer (NK) cells are important components of the innate immune defense against infections and cancers. Signal transducer and activator of transcription 1 (STAT1) is a transcription factor that is essential for NK cell maturation and NK cell-dependent tumor surveillance. Two alternatively spliced isoforms of STAT1 exist: a full-length STAT1α and a C-terminally truncated STAT1β isoform. Aberrant splicing is frequently observed in cancer cells and several anti-cancer drugs interfere with the cellular splicing machinery. To investigate whether NK cell-mediated tumor surveillance is affected by a switch in STAT1 splicing, we made use of knock-in mice expressing either only the STAT1α (Stat1α/α) or the STAT1β (Stat1β/β ) isoform. NK cells from Stat1α/α mice matured normally and controlled transplanted tumor cells as efficiently as NK cells from wild-type mice. In contrast, NK cells from Stat1β/β mice showed impaired maturation and effector functions, albeit less severe than NK cells from mice that completely lack STAT1 (Stat1-/- ). Mechanistically, we show that NK cell maturation requires the presence of STAT1α in the niche rather than in NK cells themselves and that NK cell maturation depends on IFNγ signaling under homeostatic conditions. The impaired NK cell maturation in Stat1β/β mice was paralleled by decreased IL-15 receptor alpha (IL-15Rα) surface levels on dendritic cells, macrophages and monocytes. Treatment of Stat1β/β mice with exogenous IL-15/IL-15Rα complexes rescued NK cell maturation but not their effector functions. Collectively, our findings provide evidence that STAT1 isoforms are not functionally redundant in regulating NK cell activity and that the absence of STAT1α severely impairs, but does not abolish, NK cell-dependent tumor surveillance.
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Affiliation(s)
- Katrin Meissl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Natalija Simonović
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Lena Amenitsch
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Agnieszka Witalisz-Siepracka
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Klara Klein
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Caroline Lassnig
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Biomodels Austria, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Ana Puga
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Claus Vogl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Andrea Poelzl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Markus Bosmann
- Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA, United States
- Center for Thrombosis and Hemostasis, University Medical Center Mainz, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Alexander Dohnal
- Tumor Immunology, St. Anna Kinderkrebsforschung, Children’s Cancer Research Institute, Vienna, Austria
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Mathias Müller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
- Biomodels Austria, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Birgit Strobl
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
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6
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Significance of KIR like natural killer cell receptors in autoimmune disorders. Clin Immunol 2020; 216:108449. [PMID: 32376502 DOI: 10.1016/j.clim.2020.108449] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 04/21/2020] [Accepted: 04/27/2020] [Indexed: 12/26/2022]
Abstract
Killer cell immunoglobulin-like receptors (KIRs), act as the regulators for the cytolytic activity of natural killer and certain T cells by interacting with the HLA class I ligands. KIRs have been shown to contribute to the pathogenesis of several autoimmune diseases. However, their specific roles are still not very clear. Autoimmune diseases are multifactorial in nature, highlighting the influence of both genetic and environmental factors. The innate immune response plays an important role in autoimmunity as it alters the self-glycans that mimic molecular patterns found on different intracellular pathogens. Natural killer (NK) cells have an important position in the innate immune response. NK cell receptors are encoded by the leukocyte receptor complex located on the chromosome 19q13.4 and lectin-like receptors on chromosome 12p13. This review focuses on the role of KIRs and their relationship with different autoimmune diseases.
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7
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Goodall KJ, Nguyen A, Sullivan LC, Andrews DM. The expanding role of murine class Ib MHC in the development and activation of Natural Killer cells. Mol Immunol 2018; 115:31-38. [PMID: 29789149 DOI: 10.1016/j.molimm.2018.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 04/21/2018] [Accepted: 05/02/2018] [Indexed: 12/12/2022]
Abstract
Major Histocompatibility Complex-I (MHC-I) molecules can be divided into class Ia and class Ib, with three distinct class Ib families found in the mouse. These families are designated as Q, T and M and are largely unexplored in terms of their immunological function. Among the class Ib MHC, H2-T23 (Qa-1b) has been a significant target for Natural Killer (NK) cell research, owing to its homology with the human class Ib human leukocyte antigen (HLA)-E. However, recent data has indicated that members of the Q and M family of class Ib MHC also play a critical role in the development and regulation NK cells. Here we discuss the recent advances in the control of NK cells by murine class Ib MHC as a means to stimulate further exploration of these molecules.
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Affiliation(s)
- Katharine J Goodall
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Australia
| | - Angela Nguyen
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Australia
| | - Lucy C Sullivan
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Daniel M Andrews
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Australia.
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8
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Wilk AJ, Blish CA. Diversification of human NK cells: Lessons from deep profiling. J Leukoc Biol 2018; 103:629-641. [PMID: 29350874 PMCID: PMC6133712 DOI: 10.1002/jlb.6ri0917-390r] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/06/2017] [Accepted: 12/29/2017] [Indexed: 12/14/2022] Open
Abstract
NK cells are innate lymphocytes with important roles in immunoregulation, immunosurveillance, and cytokine production. Originally defined on the functional basis of their "natural" ability to lyse tumor targets and thought to be a relatively homogeneous group of lymphocytes, NK cells possess a remarkable degree of phenotypic and functional diversity due to the combinatorial expression of an array of activating and inhibitory receptors. Diversification of NK cells is multifaceted: mechanisms of NK cell education that promote self-tolerance result in a heterogeneous repertoire that further diversifies upon encounters with viral pathogens. Here, we review the genetic, developmental, and environmental sources of NK cell diversity with a particular focus on deep profiling and single-cell technologies that will enable a more thorough and accurate dissection of this intricate and poorly understood lymphocyte lineage.
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Affiliation(s)
- Aaron J. Wilk
- Medical Scientist Training Program, Stanford University School of Medicine, Stanford, CA, USA
| | - Catherine A. Blish
- Medical Scientist Training Program, Stanford University School of Medicine, Stanford, CA, USA
- Department of Medicine, and Stanford Immunology, Stanford University School of Medicine, Stanford, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
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9
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Immunoreceptor tyrosine-based inhibitory motif-dependent functions of an MHC class I-specific NK cell receptor. Proc Natl Acad Sci U S A 2017; 114:E8440-E8447. [PMID: 28923946 DOI: 10.1073/pnas.1713064114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Natural killer (NK) cells express MHC class I (MHC-I)-specific receptors, such as Ly49A, that inhibit killing of cells expressing self-MHC-I. Self-MHC-I also "licenses" NK cells to become responsive to activating stimuli and regulates the surface level of NK-cell inhibitory receptors. However, the mechanisms of action resulting from these interactions of the Ly49s with their MHC-I ligands, particularly in vivo, have been controversial. Definitive studies could be derived from mice with targeted mutations in inhibitory Ly49s, but there are inherent challenges in specifically altering a single gene within a multigene family. Herein, we generated a knock-in mouse with a targeted mutation in the immunoreceptor tyrosine-based inhibitory motif (ITIM) of Ly49A that abolished the inhibitory function of Ly49A in cytotoxicity assays. This mutant Ly49A caused a licensing defect in NK cells, but the surface expression of Ly49A was unaltered. Moreover, NK cells that expressed this mutant Ly49A exhibited an altered inhibitory receptor repertoire. These results demonstrate that Ly49A ITIM signaling is critical for NK-cell effector inhibition, licensing, and receptor repertoire development.
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10
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Freund J, May RM, Yang E, Li H, McCullen M, Zhang B, Lenvik T, Cichocki F, Anderson SK, Kambayashi T. Activating Receptor Signals Drive Receptor Diversity in Developing Natural Killer Cells. PLoS Biol 2016; 14:e1002526. [PMID: 27500644 PMCID: PMC4976927 DOI: 10.1371/journal.pbio.1002526] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/07/2016] [Indexed: 12/20/2022] Open
Abstract
It has recently been appreciated that NK cells exhibit many features reminiscent of adaptive immune cells. Considerable heterogeneity exists with respect to the ligand specificity of individual NK cells and as such, a subset of NK cells can respond, expand, and differentiate into memory-like cells in a ligand-specific manner. MHC I-binding inhibitory receptors, including those belonging to the Ly49 and KIR families, are expressed in a variegated manner, which creates ligand-specific diversity within the NK cell pool. However, how NK cells determine which inhibitory receptors to express on their cell surface during a narrow window of development is largely unknown. In this manuscript, we demonstrate that signals from activating receptors are critical for induction of Ly49 and KIR receptors during NK cell development; activating receptor-derived signals increased the probability of the Ly49 bidirectional Pro1 promoter to transcribe in the forward versus the reverse direction, leading to stable expression of Ly49 receptors in mature NK cells. Our data support a model where the balance of activating and inhibitory receptor signaling in NK cells selects for the induction of appropriate inhibitory receptors during development, which NK cells use to create a diverse pool of ligand-specific NK cells.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/immunology
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Cells, Cultured
- Flow Cytometry
- Genetic Variation/immunology
- Histocompatibility Antigens Class I/immunology
- Histocompatibility Antigens Class I/metabolism
- Humans
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Ligands
- Mice, Inbred C57BL
- Mice, Knockout
- NK Cell Lectin-Like Receptor Subfamily A/genetics
- NK Cell Lectin-Like Receptor Subfamily A/immunology
- NK Cell Lectin-Like Receptor Subfamily A/metabolism
- Phosphoproteins/genetics
- Phosphoproteins/immunology
- Phosphoproteins/metabolism
- RNA Interference
- Receptors, KIR/immunology
- Receptors, KIR/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/genetics
- Signal Transduction/immunology
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Affiliation(s)
- Jacquelyn Freund
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Rebecca M. May
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Enjun Yang
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Hongchuan Li
- Basic Science Program, Leidos Biomedical Research Inc., Frederick National Lab, Frederick, Maryland, United States of America
| | - Matthew McCullen
- Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Bin Zhang
- Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Todd Lenvik
- Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Frank Cichocki
- Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Stephen K. Anderson
- Basic Science Program, Leidos Biomedical Research Inc., Frederick National Lab, Frederick, Maryland, United States of America
- Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Taku Kambayashi
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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11
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Forbes CA, Scalzo AA, Degli-Esposti MA, Coudert JD. Ly49C Impairs NK Cell Memory in Mouse Cytomegalovirus Infection. THE JOURNAL OF IMMUNOLOGY 2016; 197:128-40. [PMID: 27233959 DOI: 10.4049/jimmunol.1600199] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/03/2016] [Indexed: 01/06/2023]
Abstract
NK cells possess inhibitory receptors that are responsible for self-MHC class I recognition; beyond their inhibitory function, accumulating evidence indicates that such receptors confer NK cell functional competence through an unclear process termed "licensing." Ly49C is the main self-specific inhibitory Ly49 receptor in H-2(b) C57BL/6 (B6) mice. We used B6 Ly49C-transgenic and B6 β2 microglobulin (β2m)-knockout Ly49C-transgenic mice to investigate the impact of licensing through this inhibitory receptor in precursor and mature NK cells. We found that self-specific inhibitory receptors affected NK cell precursor survival and proliferation at particular developmental stages in an MHC class I-dependent manner. The presence of Ly49C impacted the NK cell repertoire in a β2m-dependent manner, with reduced Ly49A(+), Ly49G2(+), and Ly49D(+) subsets, an increased DNAM-1(+) subset, and higher NKG2D expression. Licensed NK cells displayed a skewed distribution of the maturation stages, which was characterized by differential CD27 and CD11b expression, toward the mature phenotypes. We found that Ly49C-mediated licensing induced a split effect on NK cell functions, with increased cytokine-production capabilities following engagement of various activating receptors while cytotoxicity remained unchanged. Analysis of licensed NK cell functions in vivo, in a system of mouse CMV infection, indicated that licensing did not play a major role in the NK cell antiviral response during acute infection, but it strongly impaired the generation and/or persistence of memory NK cells. This study unravels multifaceted effects of licensing on NK cell populations and their functions.
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Affiliation(s)
- Catherine A Forbes
- Centre for Experimental Immunology, Lions Eye Institute, Nedlands, Western Australia 6009, Australia; and
| | - Anthony A Scalzo
- Centre for Experimental Immunology, Lions Eye Institute, Nedlands, Western Australia 6009, Australia; and
| | - Mariapia A Degli-Esposti
- Centre for Experimental Immunology, Lions Eye Institute, Nedlands, Western Australia 6009, Australia; and Centre for Ophthalmology and Vision Science, University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Jerome D Coudert
- Centre for Experimental Immunology, Lions Eye Institute, Nedlands, Western Australia 6009, Australia; and Centre for Ophthalmology and Vision Science, University of Western Australia, Crawley, Western Australia 6009, Australia
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12
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Goodridge JP, Önfelt B, Malmberg KJ. Newtonian cell interactions shape natural killer cell education. Immunol Rev 2016; 267:197-213. [PMID: 26284479 PMCID: PMC4832384 DOI: 10.1111/imr.12325] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Newton's third law of motion states that for every action on a physical object there is an equal and opposite reaction. The dynamic change in functional potential of natural killer (NK) cells during education bears many features of such classical mechanics. Cumulative physical interactions between cells, under a constant influence of homeostatic drivers of differentiation, lead to a reactive spectrum that ultimately shapes the functionality of each NK cell. Inhibitory signaling from an array of self‐specific receptors appear not only to suppress self‐reactivity but also aid in the persistence of effector functions over time, thereby allowing the cell to gradually build up a functional potential. Conversely, the frequent non‐cytolytic interactions between normal cells in the absence of such inhibitory signaling result in continuous stimulation of the cells and attenuation of effector function. Although an innate cell, the degree to which the fate of the NK cell is predetermined versus its ability to adapt to its own environment can be revealed through a Newtonian view of NK cell education, one which is both chronological and dynamic. As such, the development of NK cell functional diversity is the product of qualitatively different physical interactions with host cells, rather than simply the sum of their signals or an imprint based on intrinsically different transcriptional programs.
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Affiliation(s)
- Jodie P Goodridge
- The KG Jebsen Center for Cancer Immunotherapy, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Björn Önfelt
- Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.,Science for Life Laboratory, Department of Applied Physics, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Karl-Johan Malmberg
- The KG Jebsen Center for Cancer Immunotherapy, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Infectious Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
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13
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Kadri N, Thanh TL, Höglund P. Selection, tuning, and adaptation in mouse NK cell education. Immunol Rev 2016; 267:167-77. [PMID: 26284477 DOI: 10.1111/imr.12330] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Natural killer (NK) cells recognize transformed cells with an array of germline-encoded inhibitory and activating receptors. Inhibitory Ly49 receptors bind major histocompatibility complex class I (MHC-I) molecules, providing a mechanism by which NK cells maintain self-tolerance yet eliminate cells expressing reduced levels of MHC-I. Additionally, MHC-I molecules are required for NK cell education, a process in which NK cells acquire responsiveness. In this review, we discuss three facets of MHC class I-dependent education of mouse NK cells: skewing of the inhibitory receptor repertoire, induction of functional responsiveness, and tuning in response to changes in MHC-I expression. We discuss prevailing models for education such as licensing and disarming and propose a model for positive selection of 'useful' NK cell subsets. Furthermore, we argue that both repertoire skewing and functional NK cell education may be altered in mature NK cells subject to changes in MHC-I input and suggest that this process may provide increased dynamics to the NK cell system.
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Affiliation(s)
- Nadir Kadri
- Center for Hematology and Regenerative Medicine (HERM), Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Thuy Luu Thanh
- Center for Hematology and Regenerative Medicine (HERM), Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Petter Höglund
- Center for Hematology and Regenerative Medicine (HERM), Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden.,Clinical Immunology and Transfusion Medicine, Karolinska University Hospital, Stockholm, Sweden
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14
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Manser AR, Weinhold S, Uhrberg M. Human KIR repertoires: shaped by genetic diversity and evolution. Immunol Rev 2015; 267:178-96. [DOI: 10.1111/imr.12316] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Angela R. Manser
- Institute for Transplantation Diagnostics and Cell Therapeutics; Heinrich-Heine University Düsseldorf; Medical Faculty; Düsseldorf Germany
| | - Sandra Weinhold
- Institute for Transplantation Diagnostics and Cell Therapeutics; Heinrich-Heine University Düsseldorf; Medical Faculty; Düsseldorf Germany
| | - Markus Uhrberg
- Institute for Transplantation Diagnostics and Cell Therapeutics; Heinrich-Heine University Düsseldorf; Medical Faculty; Düsseldorf Germany
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15
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Alhajjat AM, Strong BS, Lee AE, Turner LE, Wadhwani RK, Ortaldo JR, Heusel JW, Shaaban AF. Prenatal Allospecific NK Cell Tolerance Hinges on Instructive Allorecognition through the Activating Receptor during Development. THE JOURNAL OF IMMUNOLOGY 2015; 195:1506-16. [PMID: 26136432 DOI: 10.4049/jimmunol.1500463] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 06/11/2015] [Indexed: 12/24/2022]
Abstract
Little is known about how the prenatal interaction between NK cells and alloantigens shapes the developing NK cell repertoire toward tolerance or immunity. Specifically, the effect on NK cell education arising from developmental corecognition of alloantigens by activating and inhibitory receptors with shared specificity is uncharacterized. Using a murine prenatal transplantation model, we examined the manner in which this seemingly conflicting input affects NK cell licensing and repertoire formation in mixed hematopoietic chimeras. We found that prenatal NK cell tolerance arose from the elimination of phenotypically hostile NK cells that express an allospecific activating receptor without coexpressing any allospecific inhibitory receptors. Importantly, the checkpoint for the system appeared to occur centrally within the bone marrow during the final stage of NK cell maturation and hinged on the instructive recognition of allogeneic ligand by the activating receptor rather than through the inhibitory receptor as classically proposed. Residual nondeleted hostile NK cells expressing only the activating receptor exhibited an immature, anergic phenotype, but retained the capacity to upregulate inhibitory receptor expression in peripheral sites. However, the potential for this adaptive change to occur was lost in developmentally mature chimeras. Collectively, these findings illuminate the intrinsic process in which developmental allorecognition through the activating receptor regulates the emergence of durable NK cell tolerance and establishes a new paradigm to fundamentally guide future investigations of prenatal NK cell-allospecific education.
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Affiliation(s)
- Amir M Alhajjat
- Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, IA 52242
| | - Beverly S Strong
- Department of Surgery, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Amanda E Lee
- Department of Surgery, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Lucas E Turner
- Department of Surgery, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Ram K Wadhwani
- Department of Surgery, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - John R Ortaldo
- Experimental Therapeutics Section, National Cancer Institute, Frederick, MD 21702
| | - Jonathan W Heusel
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110; and Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
| | - Aimen F Shaaban
- Department of Surgery, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229;
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16
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Mickiewicz KM, Gays F, Lewis RJ, Brooks CG. Mutagenesis of Ly49B reveals key structural elements required for promiscuous binding to MHC class I molecules and new insights into the molecular evolution of Ly49s. THE JOURNAL OF IMMUNOLOGY 2014; 192:1558-69. [PMID: 24403531 DOI: 10.4049/jimmunol.1301643] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ly49B is a potentially important immunoregulator expressed on mouse myeloid cells, and it is thus an unusual member of the wider Ly49 family whose members are ordinarily found on NK cells. Ly49B displays substantial sequence divergence from other Ly49s and in particular shares virtually no amino acid sequence identity with the residues that have been reported to bind to MHC class I (cI) ligands in other Ly49s. Despite this, we show in this study that the BALB/c, but not the C57, isoform of Ly49B displays promiscuous cI binding. Binding was not significantly affected by inactivation of any of the four predicted N-linked glycosylation sites of Ly49B, nor was it affected by removal of the unique 20-aa C-terminal extension found in Ly49B. However, transfer of these C-terminal 20 aa to Ly49A inhibited cI binding, as did the addition of a hemagglutinin tag to the C terminus of Ly49B, demonstrating unexpectedly that the C-terminal region of Ly49s can play a significant role in ligand binding. Systematic exchange of BALB/c and C57 residues revealed that Trp(166), Asn(167), and Cys(251) are of major importance for cI binding in Ly49B. These residues are highly conserved in the Ly49 family. Remarkably, however, Ly49B(BALB) variants that have C57 residues at positions 166 or 167, and are unable to bind cI multimers, regain substantial cI binding when amino acid changes are made at distal positions, providing an explanation of how highly divergent Ly49s that retain the ability to bind cI molecules might have evolved.
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Affiliation(s)
- Katarzyna M Mickiewicz
- Institute of Cell and Molecular Biosciences, University of Newcastle, Newcastle NE2 4HH, United Kingdom
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17
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Abstract
The functions of Natural Killer (NK) cells are regulated by a highly redundant set of germline-encoded surface receptors that can inhibit or activate NK cell activities. NK cells can be activated by cytokines or through the interaction with transformed or infected cells. This typically results in the production of cytokines, chemokines, and the induction of cellular cytotoxicity. However, the reactivity of NK cells is modulated on various levels and shaped by processes such as development, education, priming, exposure to antigens and cytokines, and the formation of memory-like phenotypes. Here, I will summarize our current understanding of these processes and describe how they influence NK cell reactivity on a molecular level.
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Affiliation(s)
- Carsten Watzl
- Leibniz Research Center for Working Environment and Human Factors, IfADo, Dortmund, Germany.
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18
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Bessoles S, Angelov GS, Back J, Leclercq G, Vivier E, Held W. Education of murine NK cells requires both cis and trans recognition of MHC class I molecules. THE JOURNAL OF IMMUNOLOGY 2013; 191:5044-51. [PMID: 24098052 DOI: 10.4049/jimmunol.1301971] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Although NK cells use invariant receptors to identify diseased cells, they nevertheless adapt to their environment, including the presence of certain MHC class I (MHC-I) molecules. This NK cell education, which is mediated by inhibitory receptors specific for MHC-I molecules, changes the responsiveness of activating NK cell receptors (licensing) and modifies the repertoire of MHC-I receptors used by NK cells. The fact that certain MHC-I receptors have the unusual capacity to recognize MHC-I molecules expressed by other cells (trans) and by the NK cell itself (cis) has raised the question regarding possible contributions of the two types of interactions to NK cell education. Although the analysis of an MHC-I receptor variant suggested a role for cis interaction for NK cell licensing, adoptive NK cell transfer experiments supported a key role for trans recognition. To reconcile some of these findings, we have analyzed the impact of cell type-specific deletion of an MHC-I molecule and of a novel MHC-I receptor variant on the education of murine NK cells when these mature under steady-state conditions in vivo. We find that MHC-I expression by NK cells (cis) and by T cells (trans), and MHC-I recognition in cis and in trans, are both needed for NK cell licensing. Unexpectedly, modifications of the MHC-I receptor repertoire are chiefly dependent on cis binding, which provides additional support for an essential role for this unconventional type of interaction for NK cell education. These data suggest that two separate functions of MHC-I receptors are needed to adapt NK cells to self-MHC-I.
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Affiliation(s)
- Stéphanie Bessoles
- Department of Oncology, Ludwig Center for Cancer Research, University of Lausanne, 1066 Epalinges, Switzerland
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19
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Alvarez M, Sungur CM, Ames E, Anderson SK, Pomeroy C, Murphy WJ. Contrasting effects of anti-Ly49A due to MHC class I cis binding on NK cell-mediated allogeneic bone marrow cell resistance. THE JOURNAL OF IMMUNOLOGY 2013; 191:688-98. [PMID: 23752612 DOI: 10.4049/jimmunol.1300202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NK subsets have activating and inhibitory receptors that bind MHC-I. Ly49A is a mouse inhibitory receptor that binds with high affinity to H2(d) in both a cis- and trans-manner. Ly49A cis-associations limit trans-interactions with H2(d)-expressing targets as well as mAb binding. We demonstrate that cis-interactions affect mAb effector functions. In vivo administration of anti-Ly49A depleted NK cells in H2(b) but not H2(d) mice. Despite lack of depletion, in vivo treatment with anti-Ly49A reduced NK killing capabilities and inhibited activation, partially due to its agonistic effect. These data explain the previously described in vivo effects on bone marrow allograft rejection observed with anti-Ly49A treatment in H2(d)-haplotype mice. However, prior treatment of mice with poly(I:C) or mouse CMV infection resulted in increased Ly49A expression and Ly49A(+) NK cell depletion in H2(d) mice. These data indicate that, although Ly49 mAbs can exert similar in vivo effects in mice with different MHC haplotypes, these effects are mediated via different mechanisms of action correlating with Ly49A expression levels and can be altered within the same strain contingent on stimuli. This illustrates the marked diversity of mAb effector functions due to the regulation of the level of expression of target Ags and responses by stimulatory incidents such as infection.
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Affiliation(s)
- Maite Alvarez
- Department of Dermatology, University of California, Davis, Sacramento, CA 95817, USA
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20
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Sternberg-Simon M, Brodin P, Pickman Y, Onfelt B, Kärre K, Malmberg KJ, Höglund P, Mehr R. Natural killer cell inhibitory receptor expression in humans and mice: a closer look. Front Immunol 2013; 4:65. [PMID: 23532016 PMCID: PMC3607804 DOI: 10.3389/fimmu.2013.00065] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 02/28/2013] [Indexed: 01/01/2023] Open
Abstract
The Natural Killer (NK) cell population is composed of subsets of varying sizes expressing different combinations of inhibitory receptors for MHC class I molecules. Genes within the NK gene complex, including the inhibitory receptors themselves, seem to be the primary intrinsic regulators of inhibitory receptor expression, but the MHC class I background is an additional Modulating factor. In this paper, we have performed a parallel study of the inhibitory receptor repertoire in inbred mice of the C57Bl/6 background and in a cohort of 44 humans. Deviations of subset frequencies from the “product rule (PR),” i.e., differences between observed and expected frequencies of NK cells, were used to identify MHC-independent and MHC-dependent control of receptor expression frequencies. Some deviations from the PR were similar in mice and humans, such as the decreased presence of NK cell subset lacking inhibitory receptors. Others were different, including a role for NKG2A in determining over- or under-representation of specific subsets in humans but not in mice. Thus, while human and murine inhibitory receptor repertoires differed in details, there may also be shared principles governing NK cell repertoire formation in these two species.
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Affiliation(s)
- Michal Sternberg-Simon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University Ramat-Gan, Israel
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21
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Recognition of the nonclassical MHC class I molecule H2-M3 by the receptor Ly49A regulates the licensing and activation of NK cells. Nat Immunol 2012; 13:1171-7. [PMID: 23142773 DOI: 10.1038/ni.2468] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 10/05/2012] [Indexed: 12/26/2022]
Abstract
The development and function of natural killer (NK) cells is regulated by the interaction of inhibitory receptors of the Ly49 family with distinct peptide-laden major histocompatibility complex (MHC) class I molecules, although whether the Ly49 family is able bind to other MHC class I-like molecules is unclear. Here we found that the prototypic inhibitory receptor Ly49A bound the highly conserved nonclassical MHC class I molecule H2-M3 with an affinity similar to its affinity for H-2D(d). The specific recognition of H2-M3 by Ly49A regulated the 'licensing' of NK cells and mediated 'missing-self' recognition of H2-M3-deficient bone marrow. Host peptide-H2-M3 was required for optimal NK cell activity against experimental metastases and carcinogenesis. Thus, nonclassical MHC class I molecules can act as cognate ligands for Ly49 molecules. Our results provide insight into the various mechanisms that lead to NK cell tolerance.
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22
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Abstract
Mounting evidence suggests a role for innate immunity in the early control of HIV infection, before the induction of adaptive immune responses. Among the early innate immune effector cells, dendritic cells (DCs) respond rapidly following infection aimed at arming the immune system, through the recognition of viral products via pattern recognition receptors. This early response results in the potent induction of a cascade of inflammatory cytokines, intimately involved in directly setting up an antiviral state, and indirectly activating other antiviral cells of the innate immune system. However, epidemiologic data strongly support a role for natural killer (NK) cells as critical innate mediators of antiviral control, through the recognition of virally infected cells through a network of receptors called the killer immunoglobulin-like receptors (KIRs). In this review, the early events in innate immune recognition of HIV, focused on defining the biology underlying KIR-mediated NK-cell control of HIV viral replication, are discussed.
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Affiliation(s)
- Mary Carrington
- Ragon Institute of MGH, MIT, and Harvard, Charlestown, Massachusetts, USA
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23
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Brodin P, Lakshmikanth T, Kärre K, Höglund P. Skewing of the NK Cell Repertoire by MHC Class I via Quantitatively Controlled Enrichment and Contraction of Specific Ly49 Subsets. THE JOURNAL OF IMMUNOLOGY 2012; 188:2218-26. [DOI: 10.4049/jimmunol.1102801] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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24
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Pelak K, Need AC, Fellay J, Shianna KV, Feng S, Urban TJ, Ge D, De Luca A, Martinez-Picado J, Wolinsky SM, Martinson JJ, Jamieson BD, Bream JH, Martin MP, Borrow P, Letvin NL, McMichael AJ, Haynes BF, Telenti A, Carrington M, Goldstein DB, Alter G. Copy number variation of KIR genes influences HIV-1 control. PLoS Biol 2011; 9:e1001208. [PMID: 22140359 PMCID: PMC3226550 DOI: 10.1371/journal.pbio.1001208] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 10/20/2011] [Indexed: 11/19/2022] Open
Abstract
A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3DS1 count associates with a lower viral set point if its putative ligand is present (p = 0.00028), as does an increase in KIR3DL1 count in the presence of KIR3DS1 and appropriate ligands for both receptors (p = 0.0015). We further provide functional data that demonstrate that NK cells from individuals with multiple copies of KIR3DL1, in the presence of KIR3DS1 and the appropriate ligands, inhibit HIV-1 replication more robustly, and associated with a significant expansion in the frequency of KIR3DS1+, but not KIR3DL1+, NK cells in their peripheral blood. Our results suggest that the relative amounts of these activating and inhibitory KIR play a role in regulating the peripheral expansion of highly antiviral KIR3DS1+ NK cells, which may determine differences in HIV-1 control following infection.
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Affiliation(s)
- Kimberly Pelak
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Anna C. Need
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Jacques Fellay
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
- Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Kevin V. Shianna
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Sheng Feng
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, United States of America
| | - Thomas J. Urban
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Dongliang Ge
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Andrea De Luca
- Institute of Clinical Infectious Diseases, Catholic University of the Sacred Heart, Rome, Italy
- Division of Infectious Diseases, Siena University Hospital, Siena, Italy
| | - Javier Martinez-Picado
- irsiCaixa Foundation and Hospital Germans Trias i Pujol, Badalona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Steven M. Wolinsky
- Division of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Jeremy J. Martinson
- Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Beth D. Jamieson
- Department of Medicine, David Geffen School of Medicine, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Jay H. Bream
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Maureen P. Martin
- Cancer and Inflammation Program, Laboratory of Experimental Immunology, SAIC-Frederick, Inc., NCI-Frederick, Frederick, Maryland, United States of America
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford and Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, United Kingdom
| | - Norman L. Letvin
- Division of Viral Pathogenesis, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrew J. McMichael
- Medical Research Council Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University, Durham, North Carolina, United States of America
| | - Amalio Telenti
- Institute of Microbiology, University Hospital Center; and University of Lausanne, Lausanne, Switzerland
| | - Mary Carrington
- Department of Medicine, David Geffen School of Medicine, University of California–Los Angeles, Los Angeles, California, United States of America
- Ragon Institute of MGH, MIT and Harvard, Boston, Massachusetts, United States of America
| | - David B. Goldstein
- Center for Human Genome Variation, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Galit Alter
- Ragon Institute of MGH, MIT and Harvard, Boston, Massachusetts, United States of America
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25
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Analyses of HLA-C–specific KIR repertoires in donors with group A and B haplotypes suggest a ligand-instructed model of NK cell receptor acquisition. Blood 2011; 117:98-107. [DOI: 10.1182/blood-2010-03-273656] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Abstract
To determine the influence of KIR and HLA class I polymorphism on human NK cell repertoires, 32 different clonotypes representing all possible combinations of 4 inhibitory KIR and NKG2A were analyzed by multicolor flow cytometry. In donors homozygous for the common group A KIR haplotype, a significant influence of HLA-C ligands was seen: KIR repertoires were dominated by clonotypes expressing a single KIR for the respective cognate ligand, either the C1-specific KIR2DL3 or C2-specific KIR2DL1. In contrast, in donors possessing the polymorphic group B haplotypes, a similar adaptation to cognate HLA-C was lacking. We suggest that this discrepancy is largely the result of a suppressive effect of the group B–specific KIR2DL2 on the frequency of KIR2DL1+ NK cells. In functional assays, KIR2DL2 not only recognized C1 but also C2 ligands, showing overlapping specificity with KIR2DL1. Moreover, using an NK cell differentiation assay we show sequential acquisition of KIR2DL2 before KIR2DL1 on developing NK cells. Together, these observations are compatible with a ligand-instructed model of NK cell education, in which recognition of HLA class I by an inhibitory receptor (KIR2DL2) suppresses subsequent expression of a second receptor (KIR2DL1) of related specificity. Importantly, the ligand-instructed model fits to the observed KIR repertoires in both broad KIR haplotype groups.
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26
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Shegarfi H, Naper C, Rolstad B, Inngjerdingen M. Listeria monocytogenes infection affects a subset of Ly49-expressing NK cells in the rat. PLoS One 2010; 5:e15579. [PMID: 21179539 PMCID: PMC3002286 DOI: 10.1371/journal.pone.0015579] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Accepted: 11/12/2010] [Indexed: 01/22/2023] Open
Abstract
NK cells are protective against certain bacterial and viral infections, and their production of IFN-γ is important for the early innate immune defence against L. monocytogenes. We have previously shown that depletion of NK cells in rats leads to increased bacterial burden upon L. monocytogenes infection, and that a subset of NK cells encompassing the majority of Ly49 receptors (Ly49s3+ NK cells) contributed to this effect. In this study, we have further investigated how the Ly49s3+ NK cell subset is affected by L. monocytogenes infection. We observed an increased percentage of Ly49s3+ NK cells in the spleen and a reduction in the bone marrow within the first 48 hrs of L. monocytogenes infection. Concomitantly, we observed increased expression levels of the inflammatory chemokine receptors CCR5 and CXCR3 by Ly49s3+ bone marrow NK cells, as compared to Ly49s3− NK cells, suggesting involvement of Ly49s3+ NK cells in the early phase of infection. However, NK cell production of IFN-γ was independent of Ly49 receptor expression. Furthermore, we observed increased expression levels of MHC class I molecules on both macrophages and NK cells during the first 48 hrs of infection, paralleled by a reduction in the surface expression of Ly49s3 on NK cells. In conclusion, L. monocytogenes infection modulates the tissue distribution of Ly49s3+ NK cells, and induces increased MHC class I expression and hence reduced surface expression of Ly49 receptors on NK cells. These changes indicate that L. monocytogenes infection may have multiple effects on NK cells in vivo, and suggests the involvement of Ly49-expressing NK cells in the immune responses towards L. monocytogenes.
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Affiliation(s)
- Hamid Shegarfi
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Christian Naper
- Institute of Immunology, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Bent Rolstad
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Marit Inngjerdingen
- Institute of Immunology, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- * E-mail:
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27
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Abstract
Natural killer (NK) cells play a key role in the immune response to certain infections and malignancies by direct cytolysis of infected or transformed cells and by secretion of potent immune mediators. NK cells express an array of activating receptors that recognize self-molecules. If not restrained by inhibitory receptors recognizing major histocompatibility complex (MHC) class I proteins on the surface of self cells, NK cells are able to kill normal, healthy cells. Not all NK cells express inhibitory receptors for self-MHC class I; thus, other tolerance mechanisms are necessary to prevent NK cell-mediated autoimmunity. Here we review the major mechanisms of NK cell education and tolerance.
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Affiliation(s)
- Mark T Orr
- Department of Microbiology and Immunology and the Cancer Research Institute, University of California, San Francisco, CA 94143, USA
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28
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Brodin P, Lakshmikanth T, Mehr R, Johansson MH, Duru AD, Achour A, Salmon-Divon M, Kärre K, Höglund P, Johansson S. Natural killer cell tolerance persists despite significant reduction of self MHC class I on normal target cells in mice. PLoS One 2010; 5. [PMID: 20957233 PMCID: PMC2949391 DOI: 10.1371/journal.pone.0013174] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Accepted: 09/03/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND A major group of murine inhibitory receptors on Natural Killer (NK) cells belong to the Ly49 receptor family and recognize MHC class I molecules. Infected or transformed target cells frequently downmodulate MHC class I molecules and can thus avoid CD8(+) T cell attack, but may at the same time develop NK cell sensitivity, due to failure to express inhibitory ligands for Ly49 receptors. The extent of MHC class I downregulation needed on normal cells to trigger NK cell effector functions is not known. METHODOLOGY/PRINCIPAL FINDINGS In this study, we show that cells expressing MHC class I to levels well below half of the host level are tolerated in an in vivo assay in mice. Hemizygous expression (expression from only one allele) of MHC class I was sufficient to induce Ly49 receptor downmodulation on NK cells to a similar degree as homozygous expression, despite a strongly reduced cell surface level of MHC class I. Co-expression of weaker MHC class I ligands in the host did not have any further effect on the degree of Ly49 downmodulation. Furthermore, a single MHC class I allele could downmodulate up to three Ly49 receptors on individual NK cells. Only when NK cells simultaneously expressed several Ly49 receptors and hemizygous MHC class I levels, a putative threshold for Ly49 downmodulation was reached. CONCLUSION Collectively, our findings suggest that in interactions between NK cells and normal untransformed cells, MHC class I molecules are in most cases expressed in excess compared to what is functionally needed to ensure self tolerance and to induce maximal Ly49 downmodulation. We speculate that the reason for this is to maintain a safety margin for otherwise normal, autologous cells over a range of MHC class I expression levels, in order to ensure robustness in NK cell tolerance.
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Affiliation(s)
- Petter Brodin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Tadepally Lakshmikanth
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Ramit Mehr
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Maria H. Johansson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Adil Doganay Duru
- Department of Medicine, Center for Infectious Medicine, Karolinska University Hospital Huddinge, Karolinska Institutet, Sweden
| | - Adnane Achour
- Department of Medicine, Center for Infectious Medicine, Karolinska University Hospital Huddinge, Karolinska Institutet, Sweden
| | - Mali Salmon-Divon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
- European Molecular Biology Laboratory (EMBL) European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
| | - Klas Kärre
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Petter Höglund
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Sofia Johansson
- Department of Applied Physics, Experimental Biomolecular Physics, Royal Institute of Technology, AlbaNova University Center, Stockholm, Sweden
- * E-mail:
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29
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Höglund P, Brodin P. Current perspectives of natural killer cell education by MHC class I molecules. Nat Rev Immunol 2010; 10:724-34. [PMID: 20818413 DOI: 10.1038/nri2835] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
From the early days of natural killer (NK) cell research, it was clear that MHC genes controlled the specificity of mouse NK cell-dependent responses, such as the ability to reject transplanted allogeneic bone marrow and to kill tumour cells. Although several mechanisms that are involved in this 'education' process have been clarified, most of the mechanisms have still to be identified. Here, we review the current understanding of the processes that are involved in NK cell education, including how the host MHC class I molecules regulate responsiveness and receptor repertoire formation in NK cells and the signalling pathways that are involved.
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Affiliation(s)
- Petter Höglund
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, SE-171 77, Stockholm, Sweden
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30
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Tolerant and diverse natural killer cell repertoires in the absence of selection. Exp Cell Res 2010; 316:1309-15. [DOI: 10.1016/j.yexcr.2010.02.030] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Accepted: 02/24/2010] [Indexed: 11/22/2022]
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31
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KIR acquisition probabilities are independent of self-HLA class I ligands and increase with cellular KIR expression. Blood 2009; 114:95-104. [DOI: 10.1182/blood-2008-10-184549] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Inhibitory killer cell immunoglobulin-like receptors (KIRs) preserve tolerance to self and shape the functional response of human natural killer (NK) cells. Here, we have evaluated the influence of selection processes in the formation of inhibitory KIR repertoires in a cohort of 44 donors homozygous for the group A KIR haplotype. Coexpression of multiple KIRs was more frequent than expected by the product rule that describes random association of independent events. In line with this observation, the probability of KIR acquisition increased with the cellular expression of KIRs. Three types of KIR repertoires were distinguished that differed in frequencies of KIR- and NKG2A-positive cells but showed no dependency on the number of self-HLA class I ligands. Furthermore, the distribution of self- and nonself-KIRs at the cell surface reflected a random combination of receptors rather than a selection process conferred by cognate HLA class I molecules. Finally, NKG2A was found to buffer overall functional responses in KIR repertoires characterized by low-KIR expression frequencies. The results provide new insights into the formation of inhibitory KIR repertoires on human NK cells and support a model in which variegated KIR repertoires are generated through sequential and random acquisition of KIRs in the absence of selection.
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32
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Johansson S, Salmon-Divon M, Johansson MH, Pickman Y, Brodin P, Kärre K, Mehr R, Höglund P. Probing natural killer cell education by Ly49 receptor expression analysis and computational modelling in single MHC class I mice. PLoS One 2009; 4:e6046. [PMID: 19557128 PMCID: PMC2699029 DOI: 10.1371/journal.pone.0006046] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 04/16/2009] [Indexed: 01/17/2023] Open
Abstract
Murine natural killer (NK) cells express inhibitory Ly49 receptors for MHC class I molecules, which allows for “missing self” recognition of cells that downregulate MHC class I expression. During murine NK cell development, host MHC class I molecules impose an “educating impact” on the NK cell pool. As a result, mice with different MHC class I expression display different frequency distributions of Ly49 receptor combinations on NK cells. Two models have been put forward to explain this impact. The two-step selection model proposes a stochastic Ly49 receptor expression followed by selection for NK cells expressing appropriate receptor combinations. The sequential model, on the other hand, proposes that each NK cell sequentially expresses Ly49 receptors until an interaction of sufficient magnitude with self-class I MHC is reached for the NK cell to mature. With the aim to clarify which one of these models is most likely to reflect the actual biological process, we simulated the two educational schemes by mathematical modelling, and fitted the results to Ly49 expression patterns, which were analyzed in mice expressing single MHC class I molecules. Our results favour the two-step selection model over the sequential model. Furthermore, the MHC class I environment favoured maturation of NK cells expressing one or a few self receptors, suggesting a possible step of positive selection in NK cell education. Based on the predicted Ly49 binding preferences revealed by the model, we also propose, that Ly49 receptors are more promiscuous than previously thought in their interactions with MHC class I molecules, which was supported by functional studies of NK cell subsets expressing individual Ly49 receptors.
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Affiliation(s)
- Sofia Johansson
- Department of Microbiology Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
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33
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Brodin P, Kärre K, Höglund P. NK cell education: not an on-off switch but a tunable rheostat. Trends Immunol 2009; 30:143-9. [PMID: 19282243 DOI: 10.1016/j.it.2009.01.006] [Citation(s) in RCA: 191] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 01/26/2009] [Accepted: 01/27/2009] [Indexed: 10/21/2022]
Abstract
Heterogeneity in the natural killer (NK) cell population is determined by variegated expression of polygenic and polymorphic receptors and distinct phenotypes and functions of NK cell subsets. Here, we outline an additional heterogeneity at the level of MHC-dependent education of NK cells. Based on data obtained using polychromatic flow cytometry and mice with single MHC class I alleles, we argue that NK cell responsiveness is tuned along a continuum determined by the strength of the inhibitory input received by the individual NK cell during education. This model has implications for the use of NK cells in therapeutic settings and affects interpretations of how NK cells control virus infections and regulate autoimmunity.
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Affiliation(s)
- Petter Brodin
- Department of Microbiology Tumor and Cell Biology, and Strategic Research Center for Studies of Integrative Recognition in the Immune System (IRIS), Karolinska Institutet, Stockholm, Sweden
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34
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Abstract
NK cells can kill transformed, infected and stressed cells while most normal cells are spared. NK cells are activated by various endogenous self-ligands, some of which are actually expressed by normal cells. Thus, NK cells are inherently self-reactive and consequently, potentially auto-aggressive. How these cells are prevented from attacking normal cells while ensuring reactivity to diseased cells is a major unresolved question for NK-cell biologists.
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Affiliation(s)
- Werner Held
- Ludwig Institute for Cancer Research, Lausanne Branch, Epalinges, Switzerland.
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35
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Abstract
Armed with potent cytotoxic and immunostimulatory effector functions, natural killer (NK) cells have the potential to cause significant damage to normal self cells unless controlled by self-tolerance mechanisms. NK cells identify and attack target cells based on integration of signals from activation and inhibitory receptors, whose ligands exhibit complex expression and/or binding patterns. Preservation of NK cell self-tolerance must therefore go beyond mere engagement of inhibitory receptors during effector functions. Herein, we review recent work that has uncovered a number of mechanisms to ensure self-tolerance of NK cells. For example, licensing of NK cells allows only NK cells that can engage self-MHC to become functionally competent, or licensed. The molecular mechanism of this phenomenon appears to require signaling by receptors that were originally identified in effector inhibition. However, the nature of the signaling event has not yet been defined, but new interpretations of several published experiments provide valuable clues. In addition, several other cell-intrinsic and -extrinsic mechanisms of NK cell tolerance are discussed, including activation receptor cooperation and synergy, cytokine stimulation, and the opposing roles of accessory and regulatory cells. Finally, NK cell tolerance is discussed as it relates to the clinic, such as KIR-HLA disease associations, tumor immunotherapy, and fetal tolerance.
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36
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Sun JC, Lanier LL. Cutting edge: viral infection breaks NK cell tolerance to "missing self". THE JOURNAL OF IMMUNOLOGY 2008; 181:7453-7. [PMID: 19017932 DOI: 10.4049/jimmunol.181.11.7453] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NK cells attack cells lacking MHC class I, yet MHC class I-deficient mice have normal numbers of NK cells with intact, albeit diminished, functions. Moreover, wild-type NK cells are tolerant of MHC class I-deficient cells in mixed bone marrow chimeras. In this study, we investigated how the absence of MHC class I affects NK cells. NK cells from beta(2)-microglobulin-deficient (B2m(-/-)) and wild-type mice exhibit similar phenotypic and functional characteristics. Both B2m(-/-) and wild-type Ly49H(+) NK cells proliferated robustly and produced IFN-gamma after infection with mouse CMV. NK cells in mixed wild-type:B2m(-/-) chimeric mice were initially tolerant of MHC class I-deficient host cells. However, this tolerance was gradually lost over time and after mouse CMV infection was rapidly broken, with a pronounced rejection of host B2m(-/-) hematopoietic cells. Thus, although NK cells can be held in check against "missing self," acute inflammation driven by infection can rapidly break established self-tolerance.
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Affiliation(s)
- Joseph C Sun
- Department of Microbiology and Immunology and the Cancer Research Institute, University of California, San Francisco, CA 94143, USA
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37
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Joncker NT, Raulet DH. Regulation of NK cell responsiveness to achieve self-tolerance and maximal responses to diseased target cells. Immunol Rev 2008; 224:85-97. [PMID: 18759922 DOI: 10.1111/j.1600-065x.2008.00658.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Inhibitory receptors specific for major histocompatibility complex (MHC) class I molecules govern the capacity of natural killer (NK) cells to attack class I-deficient cells ('missing-self recognition'). These receptors are expressed stochastically, such that the panel of expressed receptors varies between NK cells. This review addresses how the activity of NK cells is coordinated in the face of this variation to achieve a repertoire that is self-tolerant and optimally reactive with diseased cells. Recent studies show that NK cells arise in normal animals or humans that lack any known inhibitory receptors specific for self-MHC class I. These NK cells exhibit self-tolerance and exhibit functional hyporesponsiveness to stimulation through various activating receptors. Evidence suggests that hyporesponsiveness is induced because these NK cells cannot engage inhibitory MHC class I molecules and are therefore persistently over-stimulated by normal cells in the environment. Finally, we discuss evidence that hyporesponsiveness is a quantitative trait that varies depending on the balance of signals encountered by developing NK cells. Thus, a tuning process determines the functional set-point of NK cells, providing a basis for discriminating self from missing-self, and at the same time endowing each NK cell with the highest inherent responsiveness compatible with self-tolerance.
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Affiliation(s)
- Nathalie T Joncker
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720-3200, USA
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38
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A combined genotype of KIR3DL1 high expressing alleles and HLA-B*57 is associated with a reduced risk of HIV infection. AIDS 2008; 22:1487-91. [PMID: 18614872 DOI: 10.1097/qad.0b013e3282ffde7e] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Coexpression of certain combinations of natural killer cell receptor KIR3DL1 and HLA-B alleles is associated with slower time to AIDS. The strongest protection in terms of disease outcome in KIR3DL1 homozygotes (3DL1 hmz) is coexpression of HLA-B*57 and a set of KIR3DL1 genotypes (3DL1*h/*y) lacking alleles expressed at low levels on natural killer cells. We questioned whether this allele combination could also influence resistance to infection. DESIGN The genetic distribution of 3DL1*h/*y and HLA-B*57 was compared in 41 HIV-exposed uninfected and 186 recently HIV-infected 3DL1 hmz. METHODS KIR3DL1 subtyping was performed by sequencing the exons 3, 4, 5, 7-9. The major histocompatibility complex class IB locus was typed by sequence specific oligonucleotide PCR and sequencing to resolve Bw4 and Bw6 alleles and the amino acid present at position 80. RESULTS Percentage carriers of HLA-B*57 in HIV-exposed uninfected and individuals in a primary infection cohort was 12.2 and 4.3%, respectively (P = 0.0631), whereas that of 3DL1*h/*y was similar in both populations (P = 0.221). The 3DL1*h/*y-HLA-B*57 combined genotype was more frequent in exposed uninfected individuals (12.2%) than individuals in primary infection (2.7%) (P = 0.019; odds ratio, 5.03; 95% confidence intervals, 1.38-18.3). CONCLUSION Coexpression of 3DL1*h/*y and B*57, which has been associated with a reduced risk of progressing to AIDS in HIV-infected individuals also lowers the risk of HIV infection in exposed uninfected individuals.
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39
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MHC class I-specific inhibitory receptors and their ligands structure diverse human NK-cell repertoires toward a balance of missing self-response. Blood 2008; 112:2369-80. [PMID: 18583565 DOI: 10.1182/blood-2008-03-143727] [Citation(s) in RCA: 243] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Variegated expression of 6 inhibitory HLA class I-specific receptors on primary NK cells was studied using high-dimension flow cytometry in 58 humans to understand the structure and function of NK-cell repertoires. Sixty-four subsets expressing all possible receptor com-binations were present in each repertoire, and the frequency of receptor-null cells varied among the donors. Enhancement in missing-self response between NK subsets varied substantially where subset responses were defined by donor KIR/HLA allotypes, reflecting the differences in interaction between inhibitory receptors and their ligands. This contrasted to the enhancement conferred by NKG2A, which was constant and of intermediate strength. We infer a mechanism that modulates frequencies of the NK subsets displaying diverse levels of missing-self response, a system that reduces the presence of KIR-expressing subsets that display either too strong or too weak a response and effectively replaces them with NKG2A-expressing cells in the repertoire. Through this high-resolution analysis of inhibitory receptor expression, 5 types of NK-cell repertoire were defined by their content of NKG2A(+)/NKG2A(-) cells, frequency of receptor-null cells, and degree of KIR receptor coexpression. The analyses provide new perspective on how personalized human NK-cell repertoires are structured.
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40
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Awasthi A, Samarakoon A, Dai X, Wen R, Wang D, Malarkannan S. Deletion of PI3K-p85alpha gene impairs lineage commitment, terminal maturation, cytokine generation and cytotoxicity of NK cells. Genes Immun 2008; 9:522-35. [PMID: 18548087 DOI: 10.1038/gene.2008.45] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Class IA phosphotidylinositol-3-kinases (PI3Ks) are a family of p85/p110 heterodimeric lipid kinases that are important in regulating signaling events in B and T cells. However, their role in natural killer (NK) cells is not understood. Here, using mice that lack the regulatory p85alpha subunit and its alternatively spliced variants p55alpha/p50alpha (collectively termed as p85alpha(-/-)), we defined the role of PI3K in NK cell development and function. p85alpha(-/-) mice had impaired lineage commitment leading to reduced NK cellularity in the bone marrow and liver. p85alpha(-/-) NK cells showed a defective Ly49 subset specification and a decreased expression of CD43. Lack of p85alpha severely reduced the NK-mediated cytotoxicity against tumor cells representing 'induced-self' and 'missing-self'. More importantly, NKG2D and NK1.1 receptor-mediated cytokine and chemokine generation was significantly compromised in p85alpha(-/-) NK cells. These results reveal a previously unrecognized role of p85alpha in the development, terminal maturation, cytokine/chemokine generation and tumor clearance of NK cells.
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Affiliation(s)
- A Awasthi
- Laboratory of Molecular Immunology, Blood Research Institute, Milwaukee, WI, USA
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41
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Abstract
Despite early reports that natural killer (NK) cells are non-specific or have non-major histocompatibility complex (MHC)- restricted killing, it is now clear that NK cells express a panoply of receptors with defined specificity for ligands expressed on their cellular targets. The roles of these receptors in terms of physiological NK cell effector functions, such as cytotoxicity and cytokine production, are beginning to be unravelled. Inasmuch as NK cells accumulate in the uterus, an appreciation of NK cell receptor specificities and their physiological functions should provide valuable clues to the role of NK cells in the uterus and during pregnancy.
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42
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Abstract
In B lymphocytes, the B-cell adaptor for phosphatidylinositol 3-kinase (BCAP) facilitates signaling from the antigen receptor. Mice lacking BCAP have a predominantly immature pool of B cells with impaired immune function and increased susceptibility to apoptosis. Unexpectedly, we have found that natural killer (NK) cells from BCAP-deficient mice are more mature, more long-lived, more resistant to apoptosis, and exhibit enhanced functional activity compared with NK cells from wild-type mice. Surprisingly, these effects are evident despite a severe impairment of the immunoreceptor tyrosine-based activation motif-mediated Akt signaling pathway. The seemingly paradoxical phenotype reveals inherent differences in the signals controlling the final maturation of B cells and NK cells, which depend on positive and negative signals, respectively. Both enhanced interferon-gamma responses and augmented maturation of NK cells in BCAP-deficient mice are independent of available MHC class I ligands. Our data support a model in which blunting of BCAP-mediated activation signaling in developing NK cells promotes functionality, terminal maturation, and long-term survival.
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43
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Agrawal S, Tripathi P, Naik S. Roles and mechanism of natural killer cells in clinical and experimental transplantation. Expert Rev Clin Immunol 2008; 4:79-91. [DOI: 10.1586/1744666x.4.1.79] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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44
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Hayakawa Y, Watt SV, Takeda K, Smyth MJ. Distinct receptor repertoire formation in mouse NK cell subsets regulated by MHC class I expression. J Leukoc Biol 2007; 83:106-11. [DOI: 10.1189/jlb.0707496] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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45
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Benoît LA, Tan R. Xenogeneic β2-Microglobulin Substitution Alters NK Cell Function. THE JOURNAL OF IMMUNOLOGY 2007; 179:1466-74. [PMID: 17641012 DOI: 10.4049/jimmunol.179.3.1466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recently, it has been shown that human beta(2)-microglobulin (h-beta(2)m) blocks the association between the NK cell inhibitory receptor Ly49C and H-2K(b). Given this finding, we therefore sought to assess the immunobiology of NK cells derived from C57BL/6 (H-2(b)) mice expressing exclusively h-beta(2)m. Initial analysis revealed that the Ly49C expression profile of NK cells from h-beta(2)m(+) mice was modified, despite the fact that H-2K(b) expression was normal in these mice. Moreover, the NK cells were not anergic in that IL-2 treatment of h-beta(2)m(+) NK cells in vitro enabled efficient lysis of prototypic tumor cell lines as well as of syngeneic h-beta(2)m(+) lymphoblasts. This loss of self-tolerance appeared to correlate with the activation status of h-beta(2)m(+) NK cells because quiescent h-beta(2)m(+) transplant recipients maintained h-beta(2)m(+) grafts but polyinosine:polycytidylic acid-treated recipients acutely rejected h-beta(2)m(+) grafts. NK cell reactivity toward h-beta(2)m(+) targets was attributed to defective Ly49C interactions with h-beta(2)m:H-2K(b) molecules. With regard to NK cell regulatory mechanisms, we observed that h-beta(2)m:H-2K(b) complexes in the cis-configuration were inefficient at regulating Ly49C and, furthermore, that receptor-mediated uptake of h-beta(2)m:H-2K(b) by Ly49C was impaired compared with uptake of mouse beta(2)m:H-2K(b). Thus, we conclude that transgenic expression of h-beta(2)m alters self-MHC class I in such a way that it modulates the NK cell phenotype and interferes with regulatory mechanisms, which in turn causes in vitro-expanded and polyinosine:polycytidylic acid-activated NK cells to be partially self-reactive similar to what is seen with NK cells derived from MHC class I-deficient mice.
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MESH Headings
- Animals
- Cell Line, Tumor
- Cytotoxicity, Immunologic/genetics
- Female
- Graft Rejection/genetics
- Graft Rejection/immunology
- H-2 Antigens/genetics
- H-2 Antigens/immunology
- Humans
- Immunophenotyping
- Killer Cells, Lymphokine-Activated/immunology
- Killer Cells, Lymphokine-Activated/metabolism
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/transplantation
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Self Tolerance/genetics
- Self Tolerance/immunology
- beta 2-Microglobulin/biosynthesis
- beta 2-Microglobulin/deficiency
- beta 2-Microglobulin/genetics
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Affiliation(s)
- Loralyn A Benoît
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
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46
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Martin MP, Qi Y, Gao X, Yamada E, Martin JN, Pereyra F, Colombo S, Brown EE, Shupert WL, Phair J, Goedert JJ, Buchbinder S, Kirk GD, Telenti A, Connors M, O'Brien SJ, Walker BD, Parham P, Deeks SG, McVicar DW, Carrington M. Innate partnership of HLA-B and KIR3DL1 subtypes against HIV-1. Nat Genet 2007; 39:733-40. [PMID: 17496894 PMCID: PMC4135476 DOI: 10.1038/ng2035] [Citation(s) in RCA: 584] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Accepted: 03/29/2007] [Indexed: 11/09/2022]
Abstract
Allotypes of the natural killer (NK) cell receptor KIR3DL1 vary in both NK cell expression patterns and inhibitory capacity upon binding to their ligands, HLA-B Bw4 molecules, present on target cells. Using a sample size of over 1,500 human immunodeficiency virus (HIV)+ individuals, we show that various distinct allelic combinations of the KIR3DL1 and HLA-B loci significantly and strongly influence both AIDS progression and plasma HIV RNA abundance in a consistent manner. These genetic data correlate very well with previously defined functional differences that distinguish KIR3DL1 allotypes. The various epistatic effects observed here for common, distinct KIR3DL1 and HLA-B Bw4 combinations are unprecedented with regard to any pair of genetic loci in human disease, and indicate that NK cells may have a critical role in the natural history of HIV infection.
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Affiliation(s)
- Maureen P Martin
- Laboratory of Genomic Diversity, Science Applications International Corporation-Frederick, Inc., National Cancer Institute, P.O. Box B, Building 560, Frederick, Maryland 21702, USA
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47
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Abstract
Our understanding of human natural killer (NK) cell development lags far behind that of human B- or T-cell development. Much of our recent knowledge of this incomplete picture comes from experimental animal models that have aided in identifying fundamental in vivo processes, including those controlling NK cell homeostasis, self-tolerance, and the generation of a diverse NK cell repertoire. However, it has been difficult to fully understand the mechanistic details of NK cell development in humans, primarily because the in vivo cellular intermediates and microenvironments of this developmental pathway have remained elusive. Although there is general consensus that NK cell development occurs primarily within the bone marrow (BM), recent data implicate secondary lymphoid tissues as principal sites of NK cell development in humans. The strongest evidence stems from the observation that the newly described stages of human NK cell development are naturally and selectively enriched within lymph nodes and tonsils compared with blood and BM. In the current review, we provide an overview of these recent findings and discuss these in the context of existing tenets in the field of lymphocyte development.
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Affiliation(s)
- Aharon G Freud
- Medical Scientist Program, The Ohio State University, Columbus, OH 43210, USA
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48
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Abstract
Natural killer (NK) cells have potent capacities to immediately kill cellular targets and produce cytokines that may potentially damage normal self-tissues unless they are kept in check. Such tolerance mechanisms are incompletely understood. Here we discuss recent studies suggesting that NK cells undergo a host major histocompatibility complex (MHC) class I-dependent functional maturation process, termed 'licensing'. Ironically, licensing directly involves inhibitory receptors that recognize target cell MHC class I molecules and block activation of NK cells in effector responses. This process results in two types of tolerant NK cells: functionally competent (licensed) NK cells, whose effector responses are inhibited by self-MHC class I molecules through the same receptors that conferred licensing, and functionally incompetent (unlicensed) NK cells.
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Affiliation(s)
- Wayne M Yokoyama
- Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, MO 63110, USA.
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49
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Jeannet G, Coudert JD, Held W. T and B lymphocytes exert distinct effects on the homeostasis of NK cells. Eur J Immunol 2006; 36:2725-34. [PMID: 16955521 DOI: 10.1002/eji.200636011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
There is growing evidence that lymphocytes impact the development and/or function of other lymphocyte populations. Based on such observations we have tested whether the NK cell compartment was phenotypically and functionally altered in the absence of B and/or T cells. Here we show that T cell deficiency significantly accelerates BM NK cell production and the subsequent seeding of splenic and liver NK cell compartments. In contrast, B cell deficiency reduces splenic NK cell survival. In the absence of T and B cells, the size of the NK cell compartments is determined by the combination of these positive and negative effects. Even though NK cell homeostasis is significantly altered, NK cells from T and/or B cell-deficient mice show a normal capacity to kill a susceptible target cell line and to produce IFN. Nevertheless, we noted that the usage of MHC class I-specific Ly49 family receptors was significantly altered in the absence of T and/or B cells. In general, B cell deficiency expanded Ly49 receptor usage, while T cell deficiency exerted both positive and negative effects. These findings show that B and T cells significantly and differentially influence the homeostasis and the phenotype of NK cells.
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Affiliation(s)
- Grégoire Jeannet
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland
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50
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Abstract
Natural killer (NK) cells are important mediators of resistance against tumor growth and metastasis. NK cell reactivity is regulated by a balance of signals from activating and inhibitory receptors. While reactivity against tumor cells is beneficial, it is essential that NK cells do not attack normal tissue. The distinction between tumor cells and normal cells is partly made at the level of activating receptors: transformation often results in induction of ligands for such receptors. In addition, NK cells discriminate self from non-self using MHC class I-binding inhibitory receptors. Host MHC class I molecules regulate development of NK cell reactivity and tolerance, a process that is not well understood. Recent data suggest that functional maturation may not be a binary phenomenon: quantitative aspects, with regards to avidity and frequency in interactions between developing NK cells and normal cells, may be important for the generation of NK cells that are 'tuned' to optimally sensing the absence of self-MHC class I. In this article, we discuss models for development of NK cell reactivity and tolerance. Our understanding of this process may have significant implications for the use of NK cells in cancer therapy.
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Affiliation(s)
- Maria H Johansson
- Department of Microbiology, Tumor and Cell Biology and Strategic Research Center IRIS for Studies of Integrative Recognition in the Immune System, Karolinska Institutet, Stockholm, Sweden.
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