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Silva RCMC. Fas ligand intracellular signaling: does PSTPIP mediate T cell death? Apoptosis 2024; 29:1-2. [PMID: 37794219 DOI: 10.1007/s10495-023-01892-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2023] [Indexed: 10/06/2023]
Abstract
Fas and Fas ligand (FasL)-induced cell death is critical for the appropriate regulation of immune responses, especially those mediated by T cells. In this letter, several studies are discussed that reinforce the importance of FasL intracellular signaling for CD4 + T cell death, which might involve PSTPIP phosphatase and/or MAPKs.
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Affiliation(s)
- Rafael Cardoso Maciel Costa Silva
- Laboratory of Immunoreceptors and signaling, Instituto de Biofísica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
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2
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Lettau M, Janssen O. Intra- and Extracellular Effector Vesicles From Human T And NK Cells: Same-Same, but Different? Front Immunol 2022; 12:804895. [PMID: 35003134 PMCID: PMC8733945 DOI: 10.3389/fimmu.2021.804895] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/07/2021] [Indexed: 12/13/2022] Open
Abstract
Cytotoxic T lymphocytes (CTL) and Natural Killer (NK) cells utilize an overlapping effector arsenal for the elimination of target cells. It was initially proposed that all cytotoxic effector proteins are stored in lysosome-related effector vesicles (LREV) termed "secretory lysosomes" as a common storage compartment and are only released into the immunological synapse formed between the effector and target cell. The analysis of enriched LREV, however, revealed an uneven distribution of individual effectors in morphologically distinct vesicular entities. Two major populations of LREV were distinguished based on their protein content and signal requirements for degranulation. Light vesicles carrying FasL and 15 kDa granulysin are released in a PKC-dependent and Ca2+-independent manner, whereas dense granules containing perforin, granzymes and 9 kDa granulysin require Ca2+-signaling as a hallmark of classical degranulation. Notably, both types of LREV do not only contain the mentioned cytolytic effectors, but also store and transport diverse other immunomodulatory proteins including MHC class I and II, costimulatory and adhesion molecules, enzymes (i.e. CD26/DPP4) or cytokines. Interestingly, the recent analyses of CTL- or NK cell-derived extracellular vesicles (EV) revealed the presence of a related mixture of proteins in microvesicles or exosomes that in fact resemble fingerprints of the cells of origin. This overlapping protein profile indicates a direct relation of intra- and extracellular vesicles. Since EV potentially also interact with cells at distant sites (apart from the IS), they might act as additional effector vesicles or intercellular communicators in a more systemic fashion.
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Affiliation(s)
- Marcus Lettau
- Molecular Immunology, Institute of Immunology, University Hospital Schleswig-Holstein, Kiel, Germany.,Department of Internal Medicine II, Unit for Hematological Diagnostics, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Ottmar Janssen
- Molecular Immunology, Institute of Immunology, University Hospital Schleswig-Holstein, Kiel, Germany
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Manso JA, Marcos T, Ruiz-Martín V, Casas J, Alcón P, Sánchez Crespo M, Bayón Y, de Pereda JM, Alonso A. PSTPIP1-LYP phosphatase interaction: structural basis and implications for autoinflammatory disorders. Cell Mol Life Sci 2022; 79:131. [PMID: 35152348 PMCID: PMC8840930 DOI: 10.1007/s00018-022-04173-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 01/14/2022] [Accepted: 01/27/2022] [Indexed: 11/25/2022]
Abstract
AbstractMutations in the adaptor protein PSTPIP1 cause a spectrum of autoinflammatory diseases, including PAPA and PAMI; however, the mechanism underlying these diseases remains unknown. Most of these mutations lie in PSTPIP1 F-BAR domain, which binds to LYP, a protein tyrosine phosphatase associated with arthritis and lupus. To shed light on the mechanism by which these mutations generate autoinflammatory disorders, we solved the structure of the F-BAR domain of PSTPIP1 alone and bound to the C-terminal homology segment of LYP, revealing a novel mechanism of recognition of Pro-rich motifs by proteins in which a single LYP molecule binds to the PSTPIP1 F-BAR dimer. The residues R228, D246, E250, and E257 of PSTPIP1 that are mutated in immunological diseases directly interact with LYP. These findings link the disruption of the PSTPIP1/LYP interaction to these diseases, and support a critical role for LYP phosphatase in their pathogenesis.
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Affiliation(s)
- José A Manso
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), CSIC-Universidad de Salamanca, Campus Unamuno, 37007, Salamanca, Spain
| | - Tamara Marcos
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - Virginia Ruiz-Martín
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - Javier Casas
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - Pablo Alcón
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), CSIC-Universidad de Salamanca, Campus Unamuno, 37007, Salamanca, Spain
| | - Mariano Sánchez Crespo
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - Yolanda Bayón
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain
| | - José M de Pereda
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), CSIC-Universidad de Salamanca, Campus Unamuno, 37007, Salamanca, Spain
| | - Andrés Alonso
- Unidad de Excelencia Instituto de Biología y Genética Molecular (IBGM), CSIC-Universidad de Valladolid, c/ Sanz y Forés 3, 47003, Valladolid, Spain.
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The Serine Protease CD26/DPP4 in Non-Transformed and Malignant T Cells. Cancers (Basel) 2021; 13:cancers13235947. [PMID: 34885056 PMCID: PMC8657226 DOI: 10.3390/cancers13235947] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 11/23/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The transmembrane serine protease CD26/Dipeptidylpeptidase 4 modulates T-cell activation, proliferation, and effector function. Due to their remarkable tumoricidal properties CD26-positive T cells are considered promising candidates for T cell-based immunotherapies while in cutaneous T cell lymphoma CD26/DPP4 expression patterns are established markers for diagnosis and possibly prognosis. With a focus on T cells, we review current knowledge on the regulation of CD26/DPP4 expression and release, its implication in T-cell effector function and the suitability CD26/DPP4 as a diagnostic and/or prognostic factor in T-cell malignancies. Abstract CD26/Dipeptidylpeptidase 4 is a transmembrane serine protease that cleaves off N-terminal dipeptides. CD26/DPP4 is expressed on several immune cell types including T and NK cells, dendritic cells, and activated B cells. A catalytically active soluble form of CD26/DPP4 can be released from the plasma membrane. Given its wide array of substrates and interaction partners CD26/DPP4 has been implicated in numerous biological processes and effects can be dependent or independent of its enzymatic activity and are exerted by the transmembrane protein and/or the soluble form. CD26/DPP4 has been implicated in the modulation of T-cell activation and proliferation and CD26/DPP4-positive T cells are characterized by remarkable anti-tumor properties rendering them interesting candidates for T cell-based immunotherapies. Moreover, especially in cutaneous T-cell lymphoma CD26/DPP4 expression patterns emerged as an established marker for diagnosis and treatment monitoring. Surprisingly, besides a profound knowledge on substrates, interaction partners, and associated signal transduction pathways, the precise role of CD26/DPP4 for T cell-based immune responses is only partially understood.
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PSTPIP2 inhibits cisplatin-induced acute kidney injury by suppressing apoptosis of renal tubular epithelial cells. Cell Death Dis 2020; 11:1057. [PMID: 33311489 PMCID: PMC7733598 DOI: 10.1038/s41419-020-03267-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022]
Abstract
Cisplatin (CP) is an effective chemotherapeutic agent widely used in the treatment of various solid tumours. However, CP nephrotoxicity is an important limitation for CP use; currently, there is no method to ameliorate cisplatin-induced acute kidney injury (AKI). Recently, we identified a specific role of proline-serine-threonine phosphatase-interacting protein 2 (PSTPIP2) in cisplatin-induced AKI. PSTPIP2 was reported to play an important role in a variety of diseases. However, the functions of PSTPIP2 in experimental models of cisplatin-induced AKI have not been extensively studied. The present study demonstrated that cisplatin downregulated the expression of PSTPIP2 in the kidney tissue. Administration of AAV-PSTPIP2 or epithelial cell-specific overexpression of PSTPIP2 reduced cisplatin-induced kidney dysfunction and inhibited apoptosis of renal tubular epithelial cells. Small interfering RNA-based knockdown of PSTPIP2 expression abolished PSTPIP2 regulation of epithelial cell apoptosis in vitro. Histone acetylation may impact gene expression at the epigenetic level, and histone deacetylase (HDAC) inhibitors were reported to prevent cisplatin-induced nephrotoxicity. The UCSC database was used to predict that acetylation of histone H3 at lysine 27 (H3K27ac) induces binding to the PSTPIP2 promoter, and this prediction was validated by a ChIP assay. Interestingly, an HDAC-specific inhibitor (TSA) was sufficient to potently upregulate PSTPIP2 in epithelial cells. Histone acetylation-mediated silencing of PSTPIP2 may contribute to cisplatin nephrotoxicity. PSTPIP2 may serve as a potential therapeutic target in the prevention of cisplatin nephrotoxicity.
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Glukhova XA, Trizna JA, Proussakova OV, Gogvadze VG, Beletsky IP. Dephosphorylation of Fas-ligand and caveolin-1 is a prerequisite step in Fas-ligand - caveolin-1 complex formation and cell death stimulation. Cell Signal 2020; 70:109590. [PMID: 32109550 DOI: 10.1016/j.cellsig.2020.109590] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 02/11/2020] [Accepted: 02/25/2020] [Indexed: 10/24/2022]
Abstract
Fas-ligand/CD178 belongs to the TNF family proteins and is the well-characterized inducer of cell death. We showed previously that the interaction of Fas-ligand and caveolin-1 is necessary for Fas-ligand translocation to rafts, and the subsequent induction of Fas-ligand-dependent cell death. Both molecules can undergo phosphorylation, however the role of the phosphorylation state of Fas-ligand and caveolin-1 in their physical association, and consequently in of Fas - mediated cell death induction is currently unknown. In this study, we show that in control cells Fas-ligand interaction with caveolin-1 is not observed, and both molecules are phosphorylated. The intracellular part of Fas-ligand was shown to form a complex with p59Fyn-kinase. Upon cell death activation, the expression and activity of p59Fyn-kinase decreases substantially, leading to the disruption of Fas-ligand - p59Fyn-kinase association, dephosphorylation of Fas-ligand and caveolin-1, and formation of a complex between them (Fas-ligand - caveolin-1). The analysis of the effects of kinase and phosphatase inhibitors revealed that phosphorylation of Fas-ligand and caveolin-1 at tyrosine residues suppressed Fas-mediated cell death. Thus, dephosphorylation of Fas-ligand and caveolin-1 is critical for triggering Fas-ligand-mediated apoptotic pathway and cell death execution.
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Affiliation(s)
- Xenia A Glukhova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Puschino, Institutskaya st., 3, 142290, Russia
| | - Julia A Trizna
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Puschino, Institutskaya st., 3, 142290, Russia
| | - Olga V Proussakova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Puschino, Institutskaya st., 3, 142290, Russia
| | - Vladimir G Gogvadze
- Faculty of Fundamental Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Igor P Beletsky
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Puschino, Institutskaya st., 3, 142290, Russia.
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Lee WH, Seo D, Lim SG, Suk K. Reverse Signaling of Tumor Necrosis Factor Superfamily Proteins in Macrophages and Microglia: Superfamily Portrait in the Neuroimmune Interface. Front Immunol 2019; 10:262. [PMID: 30838001 PMCID: PMC6389649 DOI: 10.3389/fimmu.2019.00262] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 01/30/2019] [Indexed: 12/14/2022] Open
Abstract
The tumor necrosis factor (TNF) superfamily (TNFSF) is a protein superfamily of type II transmembrane proteins commonly containing the TNF homology domain. The superfamily contains more than 20 protein members, which can be released from the cell membrane by proteolytic cleavage. Members of the TNFSF function as cytokines and regulate diverse biological processes, including immune responses, proliferation, differentiation, apoptosis, and embryogenesis, by binding to TNFSF receptors. Many TNFSF proteins are also known to be responsible for the regulation of innate immunity and inflammation. Both receptor-mediated forward signaling and ligand-mediated reverse signaling play important roles in these processes. In this review, we discuss the functional expression and roles of various reverse signaling molecules and pathways of TNFSF members in macrophages and microglia in the central nervous system (CNS). A thorough understanding of the roles of TNFSF ligands and receptors in the activation of macrophages and microglia may improve the treatment of inflammatory diseases in the brain and periphery. In particular, TNFSF reverse signaling in microglia can be exploited to gain further insights into the functions of the neuroimmune interface in physiological and pathological processes in the CNS.
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Affiliation(s)
- Won-Ha Lee
- BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Donggun Seo
- BK21 Plus KNU Biomedical Convergence Program, Department of Pharmacology, School of Medicine, Brain Science & Engineering Institute, Kyungpook National University, Daegu, South Korea
| | - Su-Geun Lim
- BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Kyoungho Suk
- BK21 Plus KNU Biomedical Convergence Program, Department of Pharmacology, School of Medicine, Brain Science & Engineering Institute, Kyungpook National University, Daegu, South Korea
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Impairment of Fas-ligand-caveolin-1 interaction inhibits Fas-ligand translocation to rafts and Fas-ligand-induced cell death. Cell Death Dis 2018; 9:73. [PMID: 29358576 PMCID: PMC5833370 DOI: 10.1038/s41419-017-0109-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/10/2017] [Accepted: 10/24/2017] [Indexed: 11/17/2022]
Abstract
Fas-ligand/CD178 belongs to the TNF family proteins and can induce apoptosis through death receptor Fas/CD95. The important requirement for Fas-ligand-dependent cell death induction is its localization to rafts, cholesterol- and sphingolipid-enriched micro-domains of membrane, involved in regulation of different signaling complexes. Here, we demonstrate that Fas-ligand physically associates with caveolin-1, the main protein component of rafts. Experiments with cells overexpressing Fas-ligand revealed a FasL N-terminal pre-prolin-rich region, which is essential for the association with caveolin-1. We found that the N-terminal domain of Fas-ligand bears two caveolin-binding sites. The first caveolin-binding site binds the N-terminal domain of caveolin-1, whereas the second one appears to interact with the C-terminal domain of caveolin-1. The deletion of both caveolin-binding sites in Fas-ligand impairs its distribution between cellular membranes, and attenuates a Fas-ligand-induced cytotoxicity. These results demonstrate that the interaction of Fas-ligand and caveolin-1 represents a molecular basis for Fas-ligand translocation to rafts, and the subsequent induction of Fas-ligand-dependent cell death. A possibility of a similar association between other TNF family members and caveolin-1 is discussed.
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Sashchenko LP, Romanova EA, Ivanova OK, Sharapova TN, Yashin DV. FasL and the NKG2D receptor are required for the secretion of the Tag7/PGRP-S-Hsp70 complex by the cytotoxic CD8 + lymphocytes. IUBMB Life 2016; 69:30-36. [PMID: 27868339 DOI: 10.1002/iub.1587] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 10/29/2016] [Indexed: 11/07/2022]
Abstract
Tag7 (PGRP-S or PGLYRP1), while possessing an antimicrobial activity, also exhibits an antitumor effect when in complex with the major heat shock protein Hsp70. The cytotoxic Tag7-Hsp70 complex is secreted by lymphocytes after interaction with the HLA-negative tumors. Previously, we have shown that IL-2 induces formation of the CD4+ and CD8+ cytotoxic subpopulations of human lymphocytes, which kill tumor cells through the FasL-Fas interaction. Here, we show that only the CD8+ T cells are able to secrete the Tag7-Hsp70 complex. For its secretion the same proteins on the surface of the lymphocytes and target cells, which are involved in the contact lysis, are necessary as well. The interaction of Fas receptor with FasL leads to an activation of the Tag7-Hsp70 complex in the lymphocyte membrane fraction, and here FasL acts as a receptor that induces intracellular signaling in lymphocytes. An interaction of the MicA stress ligand with the NKG2D receptor is necessary for the release of this cytotoxic complex. It is possible, that CD8+ T lymphocytes interacting with a target cell can both carry out the contact killing of these cells and to secrete the cytotoxic factor. © 2016 IUBMB Life, 69(1):30-36, 2017.
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Affiliation(s)
| | - Elena A Romanova
- Institute of Gene Biology RAS, Vavilova 34/5, Moscow, 119334, Russia
| | - Olga K Ivanova
- Institute of Gene Biology RAS, Vavilova 34/5, Moscow, 119334, Russia
| | | | - Denis V Yashin
- Institute of Gene Biology RAS, Vavilova 34/5, Moscow, 119334, Russia
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Kumar BS, Kumar PS, Sowgandhi N, Prajwal BM, Mohan A, Sarma KVS, Sarma PVGK. Identification of novel mutations in CD2BP1 gene in clinically proven rheumatoid arthritis patients of south India. Eur J Med Genet 2016; 59:404-12. [PMID: 27184502 DOI: 10.1016/j.ejmg.2016.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Revised: 03/10/2016] [Accepted: 05/13/2016] [Indexed: 11/18/2022]
Abstract
Pyogenic Arthritis, Pyoderma gangrenosum, and Acne (PAPA syndrome) is a rare autosomal dominant, auto-inflammatory disease that affects joints and skin. The disease results due to mutations in the cluster of differentiation 2 binding protein 1 (CD2BP1) gene on chromosome 15q24.3. Rheumatoid arthritis (RA) is a common, genetically complex disease that affects the joints with occasional skin manifestations. Studies related to the pathophysiology of inflammation in these two disorders show a certain degree of overlap at genetic level. The present study was done to confirm the existence of such a genetic overlap between PAPA syndrome and RA in south Indian population. In the present study 100 patients who were clinically diagnosed rheumatoid arthritis and 100 apparently healthy controls were chosen and the 15 exons of CD2BP1 gene were PCR-amplified and sequenced. The sequence analysis showed that in exon 3 thirty eight patients revealed presence of novel heterozygous missense mutations p.Glu51Asp, p.Leu57Arg and p.Ala64Thr. In exons 6, 10 and 14 eight patients showed 44 novel missense mutations and two patients showed novel frame shift mutations p.(Met123_Leu416delinsThr) and p.(Thr337Profs*52) leading to truncated protein formation. Such mutations were not seen in controls. Further, the in silico analysis revealed the mutant CD2BP1 structure showed deletion of Cdc15 and SH3 domains when superimposed with the wild type CD2BP1 structure with variable RMSD values. Therefore, these structural variations in CD2BP1 gene due to the mutations could be one of the strongest reasons to demonstrate the involvement of these gene variations in the patients with rheumatoid arthritis.
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Affiliation(s)
- Bhattaram Siddhartha Kumar
- Department of Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, 517507, India
| | - Pasupuleti Santhosh Kumar
- Department of Biotechnology, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, 517507, India
| | - Nannepaga Sowgandhi
- Department of Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, 517507, India
| | - Bhattaram Manoj Prajwal
- Department of Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, 517507, India
| | - Alladi Mohan
- Department of Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, 517507, India
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The SAPHO syndrome revisited with an emphasis on spinal manifestations. Skeletal Radiol 2015; 44:9-24. [PMID: 25331355 DOI: 10.1007/s00256-014-2025-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 09/17/2014] [Accepted: 09/28/2014] [Indexed: 02/02/2023]
Abstract
The synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome includes a group of chronic, relapsing, inflammatory musculoskeletal disorders with similar manifestations, in particular synovitis, hyperostosis, and osteitis, which may or may not be associated with neutrophilic skin eruptions such as palmoplantar pustulosis and acne conglobata. The syndrome occurs at any age, can involve any skeletal site, and its imaging appearances are variable, depending on the stage/age of the lesion and imaging method. The diagnosis is difficult if there is no skin disease. Awareness of the imaging appearances, especially in the spine, may help the radiologist in avoiding misdiagnosis (e.g., infection, tumor) and unnecessary invasive procedures, while facilitating early diagnosis and selection of an effective treatment. In this article, we provide an overview of the radiological appearances of SAPHO syndrome, focusing on the magnetic resonance imaging findings of vertebral involvement, and present relevant clinical and pathological features that assist early diagnosis.
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Getachew Y, Cusimano FA, James LP, Thiele DL. The role of intrahepatic CD3+/CD4-/CD8- double negative T (DN T) cells in enhanced acetaminophen toxicity. Toxicol Appl Pharmacol 2014; 280:264-71. [PMID: 25168425 PMCID: PMC4253711 DOI: 10.1016/j.taap.2014.08.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 08/13/2014] [Accepted: 08/15/2014] [Indexed: 01/22/2023]
Abstract
UNLABELLED The role of the immune system, specifically NK, NKT and CD3 cells, in acetaminophen (APAP) induced liver injury remains inconsistently defined. In the present study, wild type (C57BL/6J) mice and granzyme B deficient (GrB -/-) mice were treated with acetaminophen to assess the role of the immune system in acute liver injury. Doses of acetaminophen that induced sub lethal liver injury in wild type mice unexpectedly produced fatal hepatotoxicity in granzyme B deficient (GrB -/-) mice. Analysis revealed that GrB -/- mice had an increased population of intrahepatic CD3 (+), CD4 (-), and CD8 (-) lymphocytes expressing the CD69 activation marker and Fas ligand. Depletion of these cells in the GrB -/- and wild type mice made them less susceptible to APAP injury, while depletion of NK1.1 (+) cells or both CD4 (+) and CD8 (+) T cells failed to provide the same hepatoprotection. Transfer of the GrB -/- IHLs further exacerbated liver injury and increased mortality in wild type mice but not in LRP/LPR mice, lacking fas expression. CONCLUSIONS Acetaminophen toxicity is enhanced by the presence of activated, FasL expressing intrahepatic CD3 (+), CD4 (-), CD8 (-), NK1.1 (-) T cells. Depletion of these cells from GrB -/- mice and wild type mice greatly reduces mortality and improves the course of liver injury recovery.
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Affiliation(s)
- Yonas Getachew
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9151, USA.
| | - Frank A Cusimano
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9151, USA
| | - Laura P James
- Department of Pediatrics, University of Arkansas, Little Rock, AR, USA
| | - Dwain L Thiele
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9151, USA
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Abstract
Lysosomes were once considered the end point of endocytosis, simply used for macromolecule degradation. They are now recognized to be dynamic organelles, able to fuse with a variety of targets and to be re-formed after fusion events. They are also now known to be the site of nutrient sensing and signaling to the cell nucleus. In addition, lysosomes are secretory organelles, with specialized machinery for regulated secretion of proteins in some cell types. The biogenesis of lysosomes and lysosome-related organelles is discussed, taking into account their dynamic nature and multiple roles.
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Ebsen H, Lettau M, Kabelitz D, Janssen O. Identification of SH3 domain proteins interacting with the cytoplasmic tail of the a disintegrin and metalloprotease 10 (ADAM10). PLoS One 2014; 9:e102899. [PMID: 25036101 PMCID: PMC4103893 DOI: 10.1371/journal.pone.0102899] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/25/2014] [Indexed: 11/19/2022] Open
Abstract
The a disintegrin and metalloproteases (ADAMs) play a pivotal role in the control of development, adhesion, migration, inflammation and cancer. Although numerous substrates of ADAM10 have been identified, the regulation of its surface expression and proteolytic activity is still poorly defined. One current hypothesis is that both processes are in part modulated by protein-protein interactions mediated by the intracellular portion of the protease. For related proteases, especially proline-rich regions serving as docking sites for Src homology domain 3 (SH3) domain-containing proteins proved to be important for mediating regulatory interactions. In order to identify ADAM10-binding SH3 domain proteins, we screened the All SH3 Domain Phager library comprising 305 human SH3 domains using a GST fusion protein with the intracellular region of human ADAM10 as a bait for selection. Of a total of 291 analyzed phage clones, we found 38 SH3 domains that were precipitated with the ADAM10-derived fusion protein but not with GST. We verified the binding to the cytosolic portion of ADAM10 for several candidates by co-immunoprecipitation and/or pull down analyses. Intriguingly, several of the identified proteins have been implicated in regulating surface appearance and/or proteolytic activity of related ADAMs. Thus, it seems likely that they also play a role in ADAM10 biology.
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Affiliation(s)
- Henriette Ebsen
- University of Kiel, Molecular Immunology, Institute for Immunology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Marcus Lettau
- University of Kiel, Molecular Immunology, Institute for Immunology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Dieter Kabelitz
- University of Kiel, Molecular Immunology, Institute for Immunology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Ottmar Janssen
- University of Kiel, Molecular Immunology, Institute for Immunology, University Hospital Schleswig-Holstein Campus Kiel, Kiel, Germany
- * E-mail:
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The F-BAR protein PSTPIP1 controls extracellular matrix degradation and filopodia formation in macrophages. Blood 2014; 123:2703-14. [PMID: 24421327 DOI: 10.1182/blood-2013-07-516948] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PSTPIP1 is a cytoskeletal adaptor and F-BAR protein that has been implicated in autoinflammatory disease, most notably in the PAPA syndrome: pyogenic sterile arthritis, pyoderma gangrenosum, and acne. However, the mechanism by which PSTPIP1 regulates the actin cytoskeleton and contributes to disease pathogenesis remains elusive. Here, we show that endogenous PSTPIP1 negatively regulates macrophage podosome organization and matrix degradation. We identify a novel PSTPIP1-R405C mutation in a patient presenting with aggressive pyoderma gangrenosum. Identification of this mutation reveals that PSTPIP1 regulates the balance of podosomes and filopodia in macrophages. The PSTPIP1-R405C mutation is in the SRC homology 3 (SH3) domain and impairs Wiskott-Aldrich syndrome protein (WASP) binding, but it does not affect interaction with protein-tyrosine phosphatase (PTP)-PEST. Accordingly, WASP inhibition reverses the elevated F-actin content, filopodia formation, and matrix degradation induced by PSTPIP1-R405C. Our results uncover a novel role for PSTPIP1 and WASP in orchestrating different types of actin-based protrusions. Our findings implicate the cytoskeletal regulatory functions of PSTPIP1 in the pathogenesis of pyoderma gangrenosum and suggest that the cytoskeleton is a rational target for therapeutic intervention in autoinflammatory disease.
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16
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Juhász K, Buzás K, Duda E. Importance of reverse signaling of the TNF superfamily in immune regulation. Expert Rev Clin Immunol 2014; 9:335-48. [DOI: 10.1586/eci.13.14] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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17
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Differential protein–protein interactions of full length human FasL and FasL fragments generated by proteolysis. Exp Cell Res 2014; 320:290-301. [DOI: 10.1016/j.yexcr.2013.11.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/25/2013] [Accepted: 11/19/2013] [Indexed: 01/14/2023]
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18
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Abstract
SAPHO syndrome is a disorder characterized by Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis. As the osteoarticular and skin manifestations often do not occur simultaneously and there are no validated diagnostic criteria, the diagnosis can be difficult. Clinical and imaging investigation is necessary to establish the many differential diagnoses of SAPHO syndrome. The etiopathogenesis involves infectious (probably Propionibacterium acnes), immunologic, and genetic factors. Treatment is based on information gathered from case reports and small series, and is related to specific skin or articular symptoms.
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Affiliation(s)
- Sueli Carneiro
- State University of Rio de Janeiro - Rua Farme de Amoedo 140/601, Ipanema, Rio de Janeiro 22420-020, Brazil
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19
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Immune modulation by Fas ligand reverse signaling: lymphocyte proliferation is attenuated by the intracellular Fas ligand domain. Blood 2011; 117:519-29. [DOI: 10.1182/blood-2010-07-292722] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Fas ligand (FasL) not only induces apoptosis in Fas receptor-bearing target cells, it is also able to transmit signals into the FasL-expressing cell via its intracellular domain (ICD). Recently, we described a Notch-like proteolytic processing of FasL that leads to the release of the FasL ICD into the cytoplasm and subsequent translocation into the nucleus where it may influence gene transcription. To study the molecular mechanism underlying such reverse FasL signaling in detail and to analyze its physiological importance in vivo, we established a knockout/knockin mouse model, in which wild-type FasL was replaced with a deletion mutant lacking the ICD. Our results demonstrate that FasL ICD signaling impairs activation-induced proliferation in B and T cells by diminishing phosphorylation of phospholipase C γ, protein kinase C, and extracellular signal-regulated kinase 1/2. We also demonstrate that the FasL ICD interacts with the transcription factor lymphoid-enhancer binding factor-1 and inhibits lymphoid-enhancer binding factor-1–dependent transcription. In vivo, plasma cell numbers, generation of germinal center B cells, and, consequently, production of antigen-specific immunoglobulin M antibodies in response to immunization with T cell–dependent or T cell–independent antigen are negatively affected in presence of the FasL ICD, suggesting that FasL reverse signaling participates in negative fine-tuning of certain immune responses.
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20
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Lettau M, Paulsen M, Schmidt H, Janssen O. Insights into the molecular regulation of FasL (CD178) biology. Eur J Cell Biol 2010; 90:456-66. [PMID: 21126798 DOI: 10.1016/j.ejcb.2010.10.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 10/07/2010] [Accepted: 10/08/2010] [Indexed: 01/26/2023] Open
Abstract
Fas ligand (FasL, CD95L, APO-1L, CD178, TNFSF6, APT1LG1) is the key death factor of receptor-triggered programmed cell death in immune cells. FasL/Fas-dependent apoptosis plays a pivotal role in activation-induced cell death, termination of immune responses, elimination of autoreactive cells, cytotoxic effector function of T and NK cells, and the establishment of immune privilege. Deregulation or functional impairment of FasL threatens the maintenance of immune homeostasis and defense and results in severe autoimmunity. In addition, FasL has been implicated as an accessory or costimulatory receptor in T cell activation. The molecular mechanisms underlying this reverse signaling capacity are, however, poorly understood and still controversially discussed. Many aspects of FasL biology have been ascribed to selective protein-protein interactions mediated by a unique polyproline region located in the membrane-proximal intracellular part of FasL. Over the past decade, we and others identified a large number of putative FasL-interacting molecules that bind to this polyproline stretch via Src homology 3 or WW domains. Individual interactions were analyzed in more detail and turned out to be crucial for the lysosomal storage, the transport and the surface appearance of the death factor and potentially also for reverse signaling. This review summarizes the work in the framework of the Collaborative Research Consortium 415 (CRC 415) and provides facts and hypotheses about FasL-interacting proteins and their potential role in FasL biology.
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Affiliation(s)
- Marcus Lettau
- Christian-Albrechts-University, Institute of Immunology, D-24105 Kiel, Germany.
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21
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Smith EJ, Allantaz F, Bennett L, Zhang D, Gao X, Wood G, Kastner DL, Punaro M, Aksentijevich I, Pascual V, Wise CA. Clinical, Molecular, and Genetic Characteristics of PAPA Syndrome: A Review. Curr Genomics 2010; 11:519-27. [PMID: 21532836 PMCID: PMC3048314 DOI: 10.2174/138920210793175921] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 08/18/2010] [Accepted: 09/01/2010] [Indexed: 12/16/2022] Open
Abstract
PAPA syndrome (Pyogenic Arthritis, Pyoderma gangrenosum, and Acne) is an autosomal dominant, hereditary auto-inflammatory disease arising from mutations in the PSTPIP1/CD2BP1 gene on chromosome 15q. These mutations produce a hyper-phosphorylated PSTPIP1 protein and alter its participation in activation of the "inflammasome" involved in interleukin-1 (IL-1β) production. Overproduction of IL-1β is a clear molecular feature of PAPA syndrome. Ongoing research is implicating other biochemical pathways that may be relevant to the distinct pyogenic inflammation of the skin and joints characteristic of this disease. This review summarizes the recent and rapidly accumulating knowledge on these molecular aspects of PAPA syndrome and related disorders.
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Affiliation(s)
- Elisabeth J Smith
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Scottish Rite Hospital for Children, Dallas, Texas 75219
- Garvan Institute of Medical Research, Sydney, NSW 2027, Australia
| | | | - Lynda Bennett
- Baylor Institute for Immunology Research, Dallas, Texas 75204
| | - Dongping Zhang
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Scottish Rite Hospital for Children, Dallas, Texas 75219
| | - Xiaochong Gao
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Scottish Rite Hospital for Children, Dallas, Texas 75219
| | - Geryl Wood
- Laboratory of Clinical Investigation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland 20892, USA
| | - Daniel L Kastner
- Laboratory of Clinical Investigation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland 20892, USA
| | - Marilynn Punaro
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Scottish Rite Hospital for Children, Dallas, Texas 75219
| | - Ivona Aksentijevich
- Laboratory of Clinical Investigation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland 20892, USA
| | | | - Carol A Wise
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Scottish Rite Hospital for Children, Dallas, Texas 75219
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22
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Shao Z, Schwarz H. CD137 ligand, a member of the tumor necrosis factor family, regulates immune responses via reverse signal transduction. J Leukoc Biol 2010; 89:21-9. [PMID: 20643812 DOI: 10.1189/jlb.0510315] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
CD137 (4-1BB, TNFR superfamily 9) and its ligand are members of the TNFR and TNF families, respectively, and are involved in the regulation of a wide range of immune activities. CD137 ligand cross-links its receptor, CD137, which is expressed on activated T cells, and costimulates T cell activities. CD137 ligand can also be expressed as a transmembrane protein on the cell surface and transmit signals into the cells on which it is expressed (reverse signaling). CD137 ligand expression is found on most types of leukocytes and on some nonimmune cells. In monocytic cells (monocytes, macrophages, and DCs), CD137 ligand signaling induces activation, migration, survival, and differentiation. The activities of T cells, B cells, hematopoietic progenitor cells, and some malignant cells are also influenced by CD137 ligand, but the physiological significance is understood only partly. As CD137 and CD137 ligand are regarded as valuable targets for immunotherapy, it is pivotal to determine which biological effects are mediated by which of the 2 molecules.
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Affiliation(s)
- Zhe Shao
- Department of Physiology and Immunology Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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23
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Weinlich R, Brunner T, Amarante-Mendes GP. Control of death receptor ligand activity by posttranslational modifications. Cell Mol Life Sci 2010; 67:1631-42. [PMID: 20306114 PMCID: PMC11115959 DOI: 10.1007/s00018-010-0289-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 01/20/2010] [Indexed: 01/26/2023]
Abstract
The death receptor ligands are involved in many physiological and pathological processes involving triggering of apoptosis, inflammation, proliferation, and activation. The expression of these molecules is reported to be tightly regulated at the transcriptional level. However, over the last few years, an increasing number of data demonstrated that the control of transcription is only one of the mechanisms that manage the expression of the death receptor ligands. Thus, this review is focused on posttranslational regulation of the three main members of this family, namely FasL, TNF-alpha, and TRAIL. We discuss here the importance of distribution, storage, and degranulation of these molecules, as well as their shedding by proteases on the control of death receptor ligands expression and activity.
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Affiliation(s)
- R Weinlich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.
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24
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Abstract
Evidence strongly suggests that excessive or protracted signaling, or both, by cell-surface or intracellular innate immune receptors is central to the pathogenesis of most autoimmune and autoinflammatory rheumatic diseases. The initiation of aberrant innate and adaptive immune responses in autoimmune diseases can be triggered by microbes and, at times, by endogenous molecules--particularly nucleic acids and related immune complexes--under sterile conditions. By contrast, most autoinflammatory syndromes are generally dependent on germline or de novo gene mutations that cause or facilitate inflammasome assembly. The consequent production of proinflammatory cytokines, principally interferon-alpha/beta and tumor necrosis factor in autoimmune diseases, and interleukin-1beta in autoinflammatory diseases, leads to the creation of autoamplification feedback loops and chronicity of these syndromes. These findings have resulted in a critical reappraisal of pathogenetic mechanisms, and provide a basis for the development of novel diagnostic and therapeutic modalities for these diseases.
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25
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Ma Y, Yang H, Qi J, Liu D, Xiong P, Xu Y, Feng W, Zheng G, Li P, Fang M, Tan Z, Zheng F, Gong F. CD2AP is indispensable to multistep cytotoxic process by NK cells. Mol Immunol 2009; 47:1074-82. [PMID: 19945749 DOI: 10.1016/j.molimm.2009.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 10/29/2009] [Accepted: 11/03/2009] [Indexed: 12/13/2022]
Abstract
CD2-associated protein (CD2AP) is a cytoplasmic protein which localizes to membrane ruffles, lipid rafts and the leading edges of cells. It is implicated in podocyte homeostasis, signal transduction, dynamic actin remodeling and also membrane trafficking during endocytosis and cytokinesis. CD2AP was reported to orchestrate receptor patterning and cytoskeletal polarity in T cell contacts and it could also modulate TCR signaling. However, whether it plays a role in NK cell killing remains unknown. In this study, we discovered that interfering with CD2AP expression strongly reduced cytotoxicity of human NK92 cell line and this effect was independent of FasL sensitivity of target cells. Conjugate formation and degranulation were impeded in NK92 cells after CD2AP knockdown. Upon encountering target cells, CD2AP in NK92 is enriched near contact site and colocalizes with FasL-bearing granules. In contrast, FasL-bearing granules were found rarely polarized toward cell contact site after CD2AP knockdown. Furthermore, by immunoprecipitation from NK92 cell lysates and transient expression studies in 293T and Hela cells, we demonstrated that CD2AP associates with FasL. Thus, CD2AP, through facilitating conjugate formation and directed transport of lytic granules, plays an important role in NK cells killing.
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Affiliation(s)
- Yuting Ma
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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26
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Voss M, Lettau M, Janssen O. Identification of SH3 domain interaction partners of human FasL (CD178) by phage display screening. BMC Immunol 2009; 10:53. [PMID: 19807924 PMCID: PMC2763855 DOI: 10.1186/1471-2172-10-53] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Accepted: 10/06/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Fas ligand is a cytotoxic effector molecule of T and NK cells which is characterized by an intracellular N-terminal polyproline region that serves as a docking site for SH3 and WW domain proteins. Several previously described Fas ligand-interacting SH3 domain proteins turned out to be crucial for the regulation of storage, expression and function of the death factor. Recent observations, however, indicate that Fas ligand is also subject to posttranslational modifications including shedding and intramembrane proteolysis. This results in the generation of short intracellular fragments that might either be degraded or translocate to the nucleus to influence transcription. So far, protein-protein interactions that specifically regulate the fate of the intracellular fragments have not been identified. RESULTS In order to further define the SH3 domain interactome of the intracellular region of Fas ligand, we now screened a human SH3 domain phage display library. In addition to known SH3 domains mediating binding to the Fas ligand proline-rich domain, we were able to identify a number of additional SH3 domains that might also associate with FasL. Potential functional implications of the new binding proteins for the death factor's biology are discussed. For Tec kinases and sorting nexins, the observed interactions were verified in cellular systems by pulldown experiments. CONCLUSION We provide an extended list of putative Fas ligand interaction partners, confirming previously identified interactions, but also introducing several novel SH3 domain proteins that might be important regulators of Fas ligand function.
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Affiliation(s)
- Matthias Voss
- Institute of Immunology, Christian-Albrechts-University of Kiel, D-24105 Kiel, Germany.
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27
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Abstract
The mouse Lupo (I282N) mutation in proline-serine-threonine phosphatase-interacting protein 2 (PSTPIP2) leads to reduced expression of PSTPIP2 that is associated with a macrophage-mediated autoinflammatory disease. Another mutation in PSTPIP2, L98P, termed chronic multifocal osteomyelits (cmo), leads to a disease in mice that resembles chronic recurrent multifocal osteomyelits in humans. The cellular basis of cmo disease was investigated. cmo disease develops independently of lymphocytes and is cured by bone marrow transplantation. Macrophages, mast cells, and osteoclasts from cmo mice fail to express detectable PSTPIP2 protein. Asymptomatic Pstpip2(cmo/cmo) mice have increased circulating levels of macrophage inflammatory protein 1-alpha and interleukin-6, and their macrophages exhibit increased production of these inflammatory mediators, which is normalized by retroviral expression of wild-type PSTPIP2. Spleens of asymptomatic cmo mice contain increased numbers of macrophage precursors, and cmo mice mobilize more macrophage precursors in response to a sterile inflammatory stimulus. Signal transducer and activator of transcription 1 is elevated in cmo splenic macrophages, which also exhibit increased colony-stimulating factor-1-stimulated proliferation and increased extracellular signal-regulated kinase 1/2 phosphorylation. PSTPIP2 overexpression in macrophages leads to the opposite phenotype. Thus, PSTPIP2 deficiency causes both an expansion of macrophage progenitors and increased responsiveness of mature macrophages to activating stimuli, which together prime the organism for exaggerated and sustained responses leading to autoinflammatory disease.
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28
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Masters SL, Simon A, Aksentijevich I, Kastner DL. Horror autoinflammaticus: the molecular pathophysiology of autoinflammatory disease (*). Annu Rev Immunol 2009; 27:621-68. [PMID: 19302049 DOI: 10.1146/annurev.immunol.25.022106.141627] [Citation(s) in RCA: 750] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The autoinflammatory diseases are characterized by seemingly unprovoked episodes of inflammation, without high-titer autoantibodies or antigen-specific T cells. The concept was proposed ten years ago with the identification of the genes underlying hereditary periodic fever syndromes. This nosology has taken root because of the dramatic advances in our knowledge of the genetic basis of both mendelian and complex autoinflammatory diseases, and with the recognition that these illnesses derive from genetic variants of the innate immune system. Herein we propose an updated classification scheme based on the molecular insights garnered over the past decade, supplanting a clinical classification that has served well but is opaque to the genetic, immunologic, and therapeutic interrelationships now before us. We define six categories of autoinflammatory disease: IL-1beta activation disorders (inflammasomopathies), NF-kappaB activation syndromes, protein misfolding disorders, complement regulatory diseases, disturbances in cytokine signaling, and macrophage activation syndromes. A system based on molecular pathophysiology will bring greater clarity to our discourse while catalyzing new hypotheses both at the bench and at the bedside.
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Affiliation(s)
- Seth L Masters
- The National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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29
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Lettau M, Paulsen M, Kabelitz D, Janssen O. FasL expression and reverse signalling. Results Probl Cell Differ 2009; 49:49-61. [PMID: 19132323 DOI: 10.1007/400_2008_21] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
FasL plays a central role in the induction of apoptosis within the immune system. It mediates activation-induced cell death (AICD) of T lymphocytes and contributes to the cytotoxic effector function of T and NK cells. Moreover, FasL is discussed as direct effector molecule for the establishment of immune privilege and tumour survival. Besides its death-promoting activity, FasL has been implicated in reverse signalling and might thus also play a role in T cell development and selection and the modulation of T cell activation. Considering these diverse functions, the overall FasL expression has to be tightly controlled to avoid unwanted damage. Based on an activation-associated transcriptional control, several post-transcriptional processes ensure a safe storage, a rapid mobilisation, a target-directed activity and a subsequent inactivation. Over the past years, the identification and characterisation of FasL-interacting proteins provided novel insight into the mechanisms of FasL transport, processing and reverse signalling, which might be exemplary also for the other members of the TNF family.
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Affiliation(s)
- M Lettau
- Institute of Immunology, University Hospital Schleswig-Holstein Campus Kiel, Michaelisstr. 5, D-24105 Kiel, Germany
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30
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Voss M, Lettau M, Paulsen M, Janssen O. Posttranslational regulation of Fas ligand function. Cell Commun Signal 2008; 6:11. [PMID: 19114018 PMCID: PMC2647539 DOI: 10.1186/1478-811x-6-11] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 12/29/2008] [Indexed: 12/29/2022] Open
Abstract
The TNF superfamily member Fas ligand acts as a prototypic death factor. Due to its ability to induce apoptosis in Fas (APO-1, CD95) expressing cells, Fas ligand participates in essential effector functions of the immune system. It is involved in natural killer cell- and T cell-mediated cytotoxicity, the establishment of immune privilege, and in termination of immune responses by induction of activation-induced cell death. In addition, Fas ligand-positive tumours may evade immune surveillance by killing Fas-positive tumour-infiltrating cells. Given these strong cytotoxic capabilities of Fas ligand, it is obvious that its function has to be strictly regulated to avoid uncontrolled damage. In hematopoietic cells, the death factor is stored in secretory lysosomes and is mobilised to the immunological synapse only upon activation. The selective sorting to and the release from this specific lysosomal compartment requires interactions of the Fas ligand cytosolic moiety, which mediates binding to various adapter proteins involved in trafficking and cytoskeletal reorganisation. In addition, Fas ligand surface expression is further regulated by posttranslational ectodomain shedding and subsequent regulated intramembrane proteolysis, releasing a soluble ectodomain cytokine into the extracellular space and an N-terminal fragment with a potential role in intracellular signalling processes. Moreover, other posttranslational modifications of the cytosolic domain, including phosphorylation and ubiquitylation, have been described to affect various aspects of Fas ligand biology. Since FasL is regarded as a potential target for immunotherapy, the further characterisation of its biological regulation and function will be of great importance for the development and evaluation of future therapeutic strategies.
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Affiliation(s)
- Matthias Voss
- Molecular Immunology, Institute of Immunology, Medical Center Schleswig-Holstein Campus Kiel, Arnold-Heller-Str, 3, Bldg, 17, D-24105 Kiel, Germany.
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31
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Bodar EJ, Drenth JPH, van der Meer JWM, Simon A. Dysregulation of innate immunity: hereditary periodic fever syndromes. Br J Haematol 2008; 144:279-302. [PMID: 19120372 DOI: 10.1111/j.1365-2141.2008.07036.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The hereditary periodic fever syndromes encompass a rare group of diseases that have lifelong recurrent episodes of inflammatory symptoms and an acute phase response in common. Clinical presentation can mimic that of lymphoproliferative disorders and patients often go undiagnosed for many years. These syndromes follow an autosomal inheritance pattern, and the major syndromes are linked to specific genes, most of which are involved in regulation of the innate immune response through pathways of apoptosis, nuclear factor kappaBeta activation and cytokine production. In others, the link between the protein involved and inflammation is less clear. The recurrent inflammation can lead to complications, such as renal impairment due to amyloidosis and vasculitis, visual impairment, hearing loss, and joint destruction, depending on the specific syndrome. In recent years, treatment options for these diseases have improved significantly. Early establishment of an accurate diagnosis and start of appropriate therapy improves prognosis in these patients.
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Affiliation(s)
- Evelien J Bodar
- Department of General Internal Medicine, Radbound University Nijmegen Medical Centre, Nijmegen, The Netherlands
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32
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Linkermann A, Gelhaus C, Lettau M, Qian J, Kabelitz D, Janssen O. Identification of interaction partners for individual SH3 domains of Fas ligand associated members of the PCH protein family in T lymphocytes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1794:168-76. [PMID: 19041431 DOI: 10.1016/j.bbapap.2008.10.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 10/27/2008] [Accepted: 10/28/2008] [Indexed: 02/08/2023]
Abstract
Pombe Cdc15 homology (PCH) family proteins are regarded as key elements for linking membrane-associated processes to cytoskeletal elements and thus play a major role in exo- and endocytosis and organelle trafficking. We previously reported that, via their SH3 domains, several members of the PCH proteins interact with the proline-rich region of Fas ligand (FasL, CD95L), a key death factor in immune cells. Since protein-protein interactions that govern the storage and transport of FasL-associated vesicles are largely unknown, the present study was performed to identify other potential binding partners for SH3 domains of FasL-interacting PCH proteins. To this end, individual SH3 domains were expressed as GST fusion proteins and used to precipitate associated proteins from leukemic T cell lines and activated human T cell blasts. 87 protein bands representing 34 individual proteins were identified by mass spectrometry. The presented list of candidate interactors not only highlights the role of PCH proteins as adapters between vesicular membranes and the cytoskeleton but also points to an involvement of these proteins in the regulation of signalling events in T lymphocytes.
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Affiliation(s)
- Andreas Linkermann
- Institute for Immunology, University Hospital Schleswig-Holstein Campus Kiel, Michaelisstr. 5, D-24105 Kiel, Germany
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33
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The adaptor protein Grb2 regulates cell surface Fas ligand in Schwann cells. Biochem Biophys Res Commun 2008; 376:341-6. [PMID: 18789888 DOI: 10.1016/j.bbrc.2008.08.164] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 08/28/2008] [Indexed: 12/24/2022]
Abstract
Fas Ligand (FasL, CD178) is a cytokine that may be secreted or expressed as a transmembrane ligand at the cell surface, and induces apoptosis by binding to the "death receptor" Fas (CD95). Here, we show that Grb2, an SH3 domain-containing adaptor protein, binds to the proline-rich domain of FasL and regulates its cell surface expression. We found that knocking down Grb2 expression decreased the amount of FasL at the cell surface and increased the abundance of intracellular vesicles containing FasL. Furthermore, we showed that Grb2 acts as an adaptor for FasL to interact with adaptin beta, a molecule known to regulate trafficking. Our data reveal that Grb2 facilitates the association of FasL with adaptin beta, and promotes sorting of FasL to the cell surface. As FasL is a potent regulator of cell death, dynamic regulation of its cell surface localization is critical for controlling local tissue remodeling and inflammation.
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34
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Schmidt H, Gelhaus C, Nebendahl M, Lettau M, Watzl C, Kabelitz D, Leippe M, Janssen O. 2-D DIGE analyses of enriched secretory lysosomes reveal heterogeneous profiles of functionally relevant proteins in leukemic and activated human NK cells. Proteomics 2008; 8:2911-25. [DOI: 10.1002/pmic.200800170] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Sun M, Fink PJ. A New Class of Reverse Signaling Costimulators Belongs to the TNF Family. THE JOURNAL OF IMMUNOLOGY 2007; 179:4307-12. [PMID: 17878324 DOI: 10.4049/jimmunol.179.7.4307] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Recent evidence shows that many molecules of the TNF family serve as counter-receptors, inducing costimulation through reverse signals in addition to delivering signals through their respective TNF receptors. In this review, we will discuss this new class of costimulators with a focus on the mechanism of costimulation transduced by reverse signaling through Fas ligand.
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Affiliation(s)
- Mingyi Sun
- Department of Immunology, University of Washington, Seattle, WA 98195, USA
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Thornhill PB, Cohn JB, Drury G, Stanford WL, Bernstein A, Desbarats J. A proteomic screen reveals novel Fas ligand interacting proteins within nervous system Schwann cells. FEBS Lett 2007; 581:4455-62. [PMID: 17761170 DOI: 10.1016/j.febslet.2007.08.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 08/10/2007] [Accepted: 08/13/2007] [Indexed: 12/21/2022]
Abstract
Fas ligand (FasL) binds Fas (CD95) to induce apoptosis or activate other signaling pathways. In addition, FasL transduces bidirectional or 'reverse signals'. The intracellular domain of FasL contains consensus sequences for phosphorylation and an extended proline rich region, which regulate its surface expression through undetermined mechanism(s). Here, we used a proteomics approach to identify novel FasL interacting proteins in Schwann cells to investigate signaling through and trafficking of this protein in the nervous system. We identified two novel FasL interacting proteins, sorting nexin 18 and adaptin beta, as well as two proteins previously identified as FasL interacting proteins in T cells, PACSIN2 and PACSIN3. These proteins are all associated with endocytosis and trafficking, highlighting the tight regulation of cell surface expression of FasL in the nervous system.
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Affiliation(s)
- Peter B Thornhill
- Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montréal, Québec, Canada H3G 1Y6
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Lettau M, Beyer A, Janssen O. Novel monoclonal antibodies for the investigation of PCH family proteins. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/sita.200600130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kirkin V, Cahuzac N, Guardiola-Serrano F, Huault S, Lückerath K, Friedmann E, Novac N, Wels WS, Martoglio B, Hueber AO, Zörnig M. The Fas ligand intracellular domain is released by ADAM10 and SPPL2a cleavage in T-cells. Cell Death Differ 2007; 14:1678-87. [PMID: 17557115 DOI: 10.1038/sj.cdd.4402175] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Fas ligand (FasL) is a type II transmembrane protein belonging to the tumor necrosis factor family. Its binding to the cognate Fas receptor triggers the apoptosis that plays a pivotal role in the maintenance of immune system homeostasis. The cell death-inducing property of FasL has been associated with its extracellular domain, which can be cleaved off by metalloprotease activity to produce soluble FasL. The fate of the remaining membrane-anchored N-terminal part of the FasL molecule has not been determined. Here we show that post-translational processing of overexpressed and endogenous FasL in T-cells by the disintegrin and metalloprotease ADAM10 generates a 17-kDa N-terminal fragment, which lacks the receptor-binding extracellular domain. This FasL remnant is membrane anchored and further processed by SPPL2a, a member of the signal peptide peptidase-like family of intramembrane-cleaving proteases. SPPL2a cleavage liberates a smaller and highly unstable fragment mainly containing the intracellular FasL domain (FasL ICD). We show that this fragment translocates to the nucleus and is capable of inhibiting gene transcription. With ADAM10 and SPPL2a we have identified two proteases implicated in FasL processing and release of the FasL ICD, which has been shown to be important for retrograde FasL signaling.
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Affiliation(s)
- V Kirkin
- Chemotherapeutisches Forschungsinstitut Georg-Speyer-Haus, Paul-Ehrlich-Strasse 42-44, 60596 Frankfurt, Germany
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Chitu V, Stanley ER. Pombe Cdc15 homology (PCH) proteins: coordinators of membrane-cytoskeletal interactions. Trends Cell Biol 2007; 17:145-56. [PMID: 17296299 DOI: 10.1016/j.tcb.2007.01.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 12/20/2006] [Accepted: 01/25/2007] [Indexed: 12/27/2022]
Abstract
Cellular adhesion, motility, endocytosis, exocytosis and cytokinesis involve the coordinated reorganization of the cytoskeleton and of the plasma membrane. The 'Pombe Cdc15 homology' (PCH) family of adaptor proteins has recently been shown to coordinate the membrane and cytoskeletal dynamics involved in these processes by curving membranes, recruiting dynamin and controlling the architecture of the actin cytoskeleton. Mutations in PCH family members or proteins that interact with them are associated with autoinflammatory, neurological or neoplastic diseases. Here, we review the nature, actions and disease associations of the vertebrate PCH family members, highlighting their fundamental roles in the regulation of processes involving membrane-cytoskeletal interactions.
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Affiliation(s)
- Violeta Chitu
- Department of Developmental Biology and Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, NY 10461, USA
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41
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Hallé M, Liu YC, Hardy S, Théberge JF, Blanchetot C, Bourdeau A, Meng TC, Tremblay ML. Caspase-3 regulates catalytic activity and scaffolding functions of the protein tyrosine phosphatase PEST, a novel modulator of the apoptotic response. Mol Cell Biol 2006; 27:1172-90. [PMID: 17130234 PMCID: PMC1800677 DOI: 10.1128/mcb.02462-05] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The protein tyrosine phosphatase PEST (PTP-PEST) is involved in the regulation of the actin cytoskeleton. Despite the emerging functions attributed to both PTPs and the actin cytoskeleton in apoptosis, the involvement of PTP-PEST in apoptotic cell death remains to be established. Using several cell-based assays, we showed that PTP-PEST participates in the regulation of apoptosis. As apoptosis progressed, a pool of PTP-PEST localized to the edge of retracting lamellipodia. Expression of PTP-PEST also sensitized cells to receptor-mediated apoptosis. Concertedly, specific degradation of PTP-PEST was observed during apoptosis. Pharmacological inhibitors, immunodepletion experiments, and in vitro cleavage assays identified caspase-3 as the primary regulator of PTP-PEST processing during apoptosis. Caspase-3 specifically cleaved PTP-PEST at the (549)DSPD motif and generated fragments, some of which displayed increased catalytic activity. Moreover, caspase-3 regulated PTP-PEST interactions with paxillin, leupaxin, Shc, and PSTPIP. PTP-PEST acted as a scaffolding molecule connecting PSTPIP to additional partners: paxillin, Shc, Csk, and activation of caspase-3 correlated with the modulation of the PTP-PEST adaptor function. In addition, cleavage of PTP-PEST facilitated cellular detachment during apoptosis. Together, our data demonstrate that PTP-PEST actively contributes to the cellular apoptotic response and reveal the importance of caspases as regulators of PTPs in apoptosis.
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Affiliation(s)
- Maxime Hallé
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Section 2, Nankang 115, Taipei, Taiwan
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Simon A, van der Meer JWM. Pathogenesis of familial periodic fever syndromes or hereditary autoinflammatory syndromes. Am J Physiol Regul Integr Comp Physiol 2006; 292:R86-98. [PMID: 16931648 DOI: 10.1152/ajpregu.00504.2006] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Familial periodic fever syndromes, otherwise known as hereditary autoinflammatory syndromes, are inherited disorders characterized by recurrent episodes of fever and inflammation. The general hypothesis is that the innate immune response in these patients is wrongly tuned, being either too sensitive to very minor stimuli or turned off too late. The genetic background of the major familial periodic fever syndromes has been unraveled, and through research into the pathophysiology, a clearer picture of the innate immune system is emerging. After an introduction on fever, interleukin-1beta and inflammasomes, which are involved in the majority of these diseases, this manuscript offers a detailed review of the pathophysiology of the cryopyrin-associated periodic syndromes, familial Mediterranean fever, the syndrome of pyogenic arthritis, pyoderma gangrenosum and acne, Blau syndrome, TNF-receptor-associated periodic syndrome and hyper-IgD and periodic fever syndrome. Despite recent major advances, there are still many questions to be answered regarding the pathogenesis of these disorders.
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Affiliation(s)
- Anna Simon
- Department of General Internal Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
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Cahuzac N, Baum W, Kirkin V, Conchonaud F, Wawrezinieck L, Marguet D, Janssen O, Zörnig M, Hueber AO. Fas ligand is localized to membrane rafts, where it displays increased cell death–inducing activity. Blood 2006; 107:2384-91. [PMID: 16282344 DOI: 10.1182/blood-2005-07-2883] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
AbstractFas ligand (FasL), a member of the TNF protein family, potently induces cell death by activating its matching receptor Fas. Fas-mediated killing plays a critical role in naturally and pathologically occurring cell death, including development and homeostasis of the immune system. In addition to its receptor-interacting and cell death–inducing extracellular domain, FasL has a well-conserved intracellular portion with a proline-rich SH3 domain–binding site probably involved in non-apoptotic functions. We report here that, as with the Fas receptor, a fraction of FasL is constitutively localized in rafts. These dynamic membrane microdomains, enriched in sphingolipids and cholesterol, are important for cell signaling and trafficking processes. We show that FasL is partially localized in rafts and that increased amounts of FasL are found in rafts after efficient FasL/Fas receptor interactions. Raft disorganization after cholesterol oxidase treatment and deletions within the intracellular FasL domain diminish raft partitioning and, most important, lead to decreased FasL killing. We conclude that FasL is recruited into lipid rafts for maximum Fas receptor contact and cell death–inducing potency. These findings raise the possibility that certain pathologic conditions may be treated by altering the cell death–inducing capability of FasL with drugs affecting its raft localization.
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Affiliation(s)
- Nathalie Cahuzac
- Institute of Signaling, Developmental Biology and Cancer Research, CNRS UMR 6543, 06189 Nice, France
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