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Mago E, Zhao X, Zhang W, Shao Q, Li P, Huang S, Ding X, Liu H, Sun T, He F, Weng D. RIP1 kinase inactivation protects against LPS-induced acute respiratory distress syndrome in mice. Int Immunopharmacol 2024; 133:112060. [PMID: 38652970 DOI: 10.1016/j.intimp.2024.112060] [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: 12/26/2023] [Revised: 03/22/2024] [Accepted: 04/08/2024] [Indexed: 04/25/2024]
Abstract
Acute respiratory distress syndrome (ARDS) is characterized by lung tissue oedema and inflammatory cell infiltration, with limited therapeutic interventions available. Receptor-interacting protein kinase 1 (RIPK1), a critical regulator of cell death and inflammation implicated in many diseases, is not fully understood in the context of ARDS. In this study, we employed RIP1 kinase-inactivated (Rip1K45A/K45A) mice and two distinct RIPK1 inhibitors to investigate the contributions of RIP1 kinase activity in lipopolysaccharide (LPS)-induced ARDS pathology. Our results indicated that RIPK1 kinase inactivation, achieved through both genetic and chemical approaches, significantly attenuated LPS-induced ARDS pathology, as demonstrated by reduced polymorphonuclear neutrophil percentage (PMN%) in alveolar lavage fluid, expression of inflammatory and fibrosis-related factors in lung tissues, as well as histological examination. Results by tunnel staining and qRT-PCR analysis indicated that RIPK1 kinase activity played a role in regulating cell apoptosis and inflammation induced by LPS administration in lung tissue. In summary, employing both pharmacological and genetic approaches, this study demonstrated that targeted RIPK1 kinase inactivation attenuates the pathological phenotype induced by LPS inhalation in an ARDS mouse model. This study enhances our understanding of the therapeutic potential of RIPK1 kinase modulation in ARDS, providing insights for the pathogenesis of ARDS.
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Affiliation(s)
- Emmauel Mago
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Xunan Zhao
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Weigao Zhang
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Qianchao Shao
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Peiqi Li
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Shuxian Huang
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Xinyu Ding
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Hu Liu
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Tingzhe Sun
- School of Life Sciences, Anqing Normal University, Anqing 246133, Anhui, China
| | - Fei He
- Department of Emergency Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China.
| | - Dan Weng
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, 200 Xiaolingwei Street, Nanjing 210094, China.
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Abstract
Regulated cell death mediated by dedicated molecular machines, known as programmed cell death, plays important roles in health and disease. Apoptosis, necroptosis and pyroptosis are three such programmed cell death modalities. The caspase family of cysteine proteases serve as key regulators of programmed cell death. During apoptosis, a cascade of caspase activation mediates signal transduction and cellular destruction, whereas pyroptosis occurs when activated caspases cleave gasdermins, which can then form pores in the plasma membrane. Necroptosis, a form of caspase-independent programmed necrosis mediated by RIPK3 and MLKL, is inhibited by caspase-8-mediated cleavage of RIPK1. Disruption of cellular homeostatic mechanisms that are essential for cell survival, such as normal ionic and redox balance and lysosomal flux, can also induce cell death without invoking programmed cell death mechanisms. Excitotoxicity, ferroptosis and lysosomal cell death are examples of such cell death modes. In this Review, we provide an overview of the major cell death mechanisms, highlighting the latest insights into their complex regulation and execution, and their relevance to human diseases.
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Affiliation(s)
- Junying Yuan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Shanghai, China.
- Shanghai Key Laboratory of Aging Studies, Shanghai, China.
| | - Dimitry Ofengeim
- Sanofi, Rare and Neurological Diseases Research, Cambridge, MA, USA.
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Yang Y, Zhang J, Lv M, Cui N, Shan B, Sun Q, Yan L, Zhang M, Zou C, Yuan J, Xu D. Defective prelamin A processing promotes unconventional necroptosis driven by nuclear RIPK1. Nat Cell Biol 2024; 26:567-580. [PMID: 38538837 DOI: 10.1038/s41556-024-01374-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/04/2024] [Indexed: 04/18/2024]
Abstract
Defects in the prelamin A processing enzyme caused by loss-of-function mutations in the ZMPSTE24 gene are responsible for a spectrum of progeroid disorders characterized by the accumulation of farnesylated prelamin A. Here we report that defective prelamin A processing triggers nuclear RIPK1-dependent signalling that leads to necroptosis and inflammation. We show that accumulated prelamin A recruits RIPK1 to the nucleus to facilitate its activation upon tumour necrosis factor stimulation in ZMPSTE24-deficient cells. Kinase-activated RIPK1 then promotes RIPK3-mediated MLKL activation in the nucleus, leading to nuclear envelope disruption and necroptosis. This signalling relies on prelamin A farnesylation, which anchors prelamin A to nuclear envelope to serve as a nucleation platform for necroptosis. Genetic inactivation of necroptosis ameliorates the progeroid phenotypes in Zmpste24-/- mice. Our findings identify an unconventional nuclear necroptosis pathway resulting from ZMPSTE24 deficiency with pathogenic consequences in progeroid disorder and suggest RIPK1 as a feasible target for prelamin A-associated progeroid disorders.
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Affiliation(s)
- Yuanxin Yang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jian Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Mingming Lv
- Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Na Cui
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Bing Shan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Qi Sun
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Lingjie Yan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mengmeng Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Chengyu Zou
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junying Yuan
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- Shanghai Key Laboratory of Aging Studies, Shanghai, China
| | - Daichao Xu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
- Shanghai Key Laboratory of Aging Studies, Shanghai, China.
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
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Wu Y, Xu Y, Sun J, Dai K, Wang Z, Zhang J. Inhibiting RIPK1-driven neuroinflammation and neuronal apoptosis mitigates brain injury following experimental subarachnoid hemorrhage. Exp Neurol 2024; 374:114705. [PMID: 38290652 DOI: 10.1016/j.expneurol.2024.114705] [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: 09/29/2023] [Revised: 01/14/2024] [Accepted: 01/26/2024] [Indexed: 02/01/2024]
Abstract
RIPK1, a receptor-interacting serine/threonine protein kinase, plays a crucial role in maintaining cellular and tissue homeostasis by integrating inflammatory responses and cell death signaling pathways including apoptosis and necroptosis, which have been implicated in diverse physiological and pathological processes. Suppression of RIPK1 activation is a promising strategy for restraining the pathological progression of many human diseases. Neuroinflammation and neuronal apoptosis are two pivotal factors in the pathogenesis of brain injury following subarachnoid hemorrhage (SAH). In this study, we established in vivo and in vitro models of SAH to investigate the activation of RIPK1 kinase in both microglia and neurons. We observed the correlation between RIPK1 kinase activity and microglia-mediated inflammation as well as neuronal apoptosis. We then investigated whether inhibition of RIPK1 could alleviate neuroinflammation and neuronal apoptosis following SAH, thereby reducing brain edema and ameliorating neurobehavioral deficits. Additionally, the underlying mechanisms were also explored. Our research findings revealed the activation of RIPK1 kinase in both microglia and neurons following SAH, as marked by the phosphorylation of RIPK1 at serine 166. The upregulation of p-RIPK1(S166) resulted in a significant augmentation of inflammatory cytokines and chemokines, including TNF-α, IL-6, IL-1α, CCL2, and CCL5, as well as neuronal apoptosis. The activation of RIPK1 in microglia and neurons following SAH could be effectively suppressed by administration of Nec-1 s, a specific inhibitor of RIPK1. Consequently, inhibition of RIPK1 resulted in a downregulation of inflammatory cytokines and chemokines and attenuation of neuronal apoptosis after SAH in vitro. Furthermore, the administration of Nec-1 s effectively mitigated neuroinflammation, neuronal apoptosis, brain edema, and neurobehavioral deficits in mice following SAH. Our findings suggest that inhibiting RIPK1 kinase represents a promising therapeutic strategy for mitigating brain injury after SAH by attenuating RIPK1-driven neuroinflammation and neuronal apoptosis.
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Affiliation(s)
- Yan Wu
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yao Xu
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jingshan Sun
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Kun Dai
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhong Wang
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China.
| | - Jian Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China.
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Petró JL, Bényei G, Bana P, Linke N, Horti F, Szabó JE, Szalai KK, Hornyánszky G, Greiner I, Éles J. Design, synthesis and biological evaluation of novel cyclic malonamide derivatives as selective RIPK1 inhibitors. Bioorg Med Chem Lett 2024; 100:129643. [PMID: 38316369 DOI: 10.1016/j.bmcl.2024.129643] [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: 11/15/2023] [Revised: 01/15/2024] [Accepted: 01/31/2024] [Indexed: 02/07/2024]
Abstract
Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) plays a key role in cell death and inflammation. RIPK1 is a well-established therapeutic target, due to the presence of a unique kinase-regulating allosteric pocket, which enables selective inhibition. Herein we used GSK2982772 as our starting point in our discovery campaign. Applying isosteric replacement, we successfully identified the malonamide scaffold, instead of the well-established serine template. Further structural optimization led to the design and synthesis of a series of analog inhibitors. The enantiomers of the most promising compound were tested on 97 different kinases. The active enantiomer proved to be kinase selective.
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Affiliation(s)
- József Levente Petró
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary.
| | - Gyula Bényei
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | - Péter Bana
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | - Nikolett Linke
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | - Ferenc Horti
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | - Judit Eszter Szabó
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | | | - Gábor Hornyánszky
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 8 Budafoki Street, Budapest H-1111, Hungary
| | - István Greiner
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
| | - János Éles
- Chemical Works of Gedeon Richter Plc, 30-32 Gyömrői Street, Budapest H-1103, Hungary
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6
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Bepari AK, Shatabda S, Reza HM. Virtual screening of flavonoids as potential RIPK1 inhibitors for neurodegeneration therapy. PeerJ 2024; 12:e16762. [PMID: 38274328 PMCID: PMC10809995 DOI: 10.7717/peerj.16762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 12/14/2023] [Indexed: 01/27/2024] Open
Abstract
Background Global prevalence of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease is increasing gradually, whereas approvals of successful therapeutics for central nervous system disorders are inadequate. Accumulating evidence suggests pivotal roles of the receptor-interacting serine/threonine-protein kinase 1 (RIPK1) in modulating neuroinflammation and necroptosis. Discoveries of potent small molecule inhibitors for RIPK1 with favorable pharmacokinetic properties could thus address the unmet medical needs in treating neurodegeneration. Methods In a structure-based virtual screening, we performed site-specific molecular docking of 4,858 flavonoids against the kinase domain of RIPK1 using AutoDock Vina. We predicted physicochemical descriptors of the top ligands using the SwissADME webserver. Binding interactions of the best ligands and the reference ligand L8D were validated using replicated 500-ns Gromacs molecular dynamics simulations and free energy calculations. Results From Vina docking, we shortlisted the top 20 flavonoids with the highest binding affinities, ranging from -11.7 to -10.6 kcal/mol. Pharmacokinetic profiling narrowed down the list to three orally bioavailable and blood-brain-barrier penetrant flavonoids: Nitiducarpin, Pinocembrin 7-O-benzoate, and Paratocarpin J. Next, trajectories of molecular dynamics simulations of the top protein-ligand complexes were analyzed for binding interactions. The root-mean-square deviation (RMSD) was 1.191 Å (±0.498 Å), 1.725 Å (±0.828 Å), 1.923 Å (±0.942 Å), 0.972 Å (±0.155 Å) for Nitiducarpin, Pinocembrin 7-O-benzoate, Paratocarpin J, and L8D, respectively. The radius of gyration (Rg) was 2.034 nm (±0.015 nm), 2.0.39 nm (± 0.025 nm), 2.053 nm (±0.021 nm), 2.037 nm (±0.016 nm) for Nitiducarpin, Pinocembrin 7-O-benzoate, Paratocarpin J, and L8D, respectively. The solvent accessible surface area (SASA) was 159.477 nm2 (±3.021 nm2), 159.661 nm2 (± 3.707 nm2), 160.755 nm2 (±4.252 nm2), 156.630 nm2 (±3.521 nm2), for Nitiducarpin, Pinocembrin 7-O-benzoate, Paratocarpin J, and L8D complexes, respectively. Therefore, lower RMSD, Rg, and SASA values demonstrated that Nitiducarpin formed the most stable complex with the target protein among the best three ligands. Finally, 2D protein-ligand interaction analysis revealed persistent hydrophobic interactions of Nitiducarpin with the critical residues of RIPK1, including the catalytic triads and the activation loop residues, implicated in the kinase activity and ligand binding. Conclusion Our target-based virtual screening identified three flavonoids as strong RIPK1 inhibitors, with Nitiducarpin exhibiting the most potent inhibitory potential. Future in vitro and in vivo studies with these ligands could offer new hope for developing effective therapeutics and improving the quality of life for individuals affected by neurodegeneration.
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Affiliation(s)
- Asim Kumar Bepari
- Department of Pharmaceutical Sciences, North South University, Dhaka, Dhaka, Bangladesh
| | - Swakkhar Shatabda
- Department of Computer Science and Engineering, United International University, Dhaka, Dhaka, Bangladesh
| | - Hasan Mahmud Reza
- Department of Pharmaceutical Sciences, North South University, Dhaka, Dhaka, Bangladesh
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Nakano H. Necroptosis and Its Involvement in Various Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1444:129-143. [PMID: 38467977 DOI: 10.1007/978-981-99-9781-7_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Necroptosis is a regulated form of cell death involved in the development of various pathological conditions. In contrast to apoptosis, plasma membrane rupture (PMR) occurs in cells in the relatively early stage of necroptosis; therefore, necroptosis induces a strong inflammatory response. Stimuli, including tumor necrosis factor (TNF), interferon (IFN)α/β, lipopolysaccharide, polyI:C, and viral infection, induce the formation of necrosomes that lead to membrane rupture and the release of intracellular contents, termed danger-associated molecular patterns (DAMPs). DAMPs are the collective term for molecules that normally reside in the cytoplasm or nucleus in living cells without inducing inflammation but induce strong inflammatory responses when released outside cells. Recent studies have provided a better understanding of the mechanisms underlying PMR and the release of DAMPs. Moreover, necroptosis is involved in various pathological conditions, and mutations in necroptosis-related genes can cause hereditary autoinflammatory syndromes. Thus, manipulating necroptosis signaling pathways may be useful for treating diseases involving necroptosis.
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Affiliation(s)
- Hiroyasu Nakano
- Department of Biochemistry, Faculty of Medicine, Toho University School of Medicine, Tokyo, Japan.
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Abstract
A signaling pathway that senses energy stress opposes necroptotic cell death.
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Affiliation(s)
- D Grahame Hardie
- School of Life Sciences, University of Dundee, Dundee, Scotland, UK
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9
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Pandey R, Bakay M, Hakonarson H. CLEC16A-An Emerging Master Regulator of Autoimmunity and Neurodegeneration. Int J Mol Sci 2023; 24:ijms24098224. [PMID: 37175930 PMCID: PMC10179542 DOI: 10.3390/ijms24098224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
CLEC16A is emerging as an important genetic risk factor for several autoimmune disorders and for Parkinson disease (PD), opening new avenues for translational research and therapeutic development. While the exact role of CLEC16A in health and disease is still being elucidated, the gene plays a critical role in the regulation of autophagy, mitophagy, endocytosis, intracellular trafficking, immune function, and in biological processes such as insulin secretion and others that are important to cellular homeostasis. As shown in both human and animal modeling studies, CLEC16A hypofunction predisposes to both autoinflammatory phenotype and neurodegeneration. While the two are clearly related, further functional studies are needed to fully understand the mechanisms involved for optimized therapeutic interventions. Based on recent data, mitophagy-inducing drugs may be warranted, and such therapy should be tested in clinical trials as these drugs would tackle the underlying pathogenic mechanism (s) and could treat or prevent symptoms of autoimmunity and neurodegeneration in individuals with CLEC16A risk variants. Accordingly, interventions directed at reversing the dysregulated mitophagy and the consequences of loss of function of CLEC16A without activating other detrimental cellular pathways could present an effective therapy. This review presents the emerging role of CLEC16A in health and disease and provides an update on the disease processes that are attributed to variants located in the CLEC16A gene, which are responsible for autoimmune disorders and neurodegeneration with emphasis on how this information is being translated into practical and effective applications in the clinic.
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Affiliation(s)
- Rahul Pandey
- Center for Applied Genomics, Children's Hospital of Philadelphia, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, PA 19104-4318, USA
| | - Marina Bakay
- Center for Applied Genomics, Children's Hospital of Philadelphia, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, PA 19104-4318, USA
| | - Hakon Hakonarson
- Center for Applied Genomics, Children's Hospital of Philadelphia, Abramson Research Center, 3615 Civic Center Boulevard, Philadelphia, PA 19104-4318, USA
- Department of Pediatrics, The University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4318, USA
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10
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Mocarski ES. Programmed Necrosis in Host Defense. Curr Top Microbiol Immunol 2023; 442:1-40. [PMID: 37563336 DOI: 10.1007/82_2023_264] [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] [Indexed: 08/12/2023]
Abstract
Host control over infectious disease relies on the ability of cells in multicellular organisms to detect and defend against pathogens to prevent disease. Evolution affords mammals with a wide variety of independent immune mechanisms to control or eliminate invading infectious agents. Many pathogens acquire functions to deflect these immune mechanisms and promote infection. Following successful invasion of a host, cell autonomous signaling pathways drive the production of inflammatory cytokines, deployment of restriction factors and induction of cell death. Combined, these innate immune mechanisms attract dendritic cells, neutrophils and macrophages as well as innate lymphoid cells such as natural killer cells that all help control infection. Eventually, the development of adaptive pathogen-specific immunity clears infection and provides immune memory of the encounter. For obligate intracellular pathogens such as viruses, diverse cell death pathways make a pivotal contribution to early control by eliminating host cells before progeny are produced. Pro-apoptotic caspase-8 activity (along with caspase-10 in humans) executes extrinsic apoptosis, a nonlytic form of cell death triggered by TNF family death receptors (DRs). Over the past two decades, alternate extrinsic apoptosis and necroptosis outcomes have been described. Programmed necrosis, or necroptosis, occurs when receptor interacting protein kinase 3 (RIPK3) activates mixed lineage kinase-like (MLKL), causing cell leakage. Thus, activation of DRs, toll-like receptors (TLRs) or pathogen sensor Z-nucleic acid binding protein 1 (ZBP1) initiates apoptosis as well as necroptosis if not blocked by virus-encoded inhibitors. Mammalian cell death pathways are blocked by herpesvirus- and poxvirus-encoded cell death suppressors. Growing evidence has revealed the importance of Z-nucleic acid sensor, ZBP1, in the cell autonomous recognition of both DNA and RNA virus infection. This volume will explore the detente between viruses and cells to manage death machinery and avoid elimination to support dissemination within the host animal.
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Affiliation(s)
- Edward S Mocarski
- Robert W. Woodruff Professor Emeritus, Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, 30322, USA.
- Professor Emeritus, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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