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Abstract
Numerous risk alleles for systemic lupus erythematosus (SLE) have now been identified. Analysis of the expression of genes with risk alleles in cells of hematopoietic origin demonstrates them to be most abundantly expressed in B cells and dendritic cells (DCs), suggesting that these cell types may be the drivers of the inflammatory changes seen in SLE. DCs are of particular interest as they act to connect the innate and the adaptive immune response. Thus, DCs can transform inflammation into autoimmunity, and autoantibodies are the hallmark of SLE. In this review, we focus on mechanisms of tolerance that maintain DCs in a non‐activated, non‐immunogenic state. We demonstrate, using examples from our own studies, how alterations in DC function stemming from either DC‐intrinsic abnormalities or DC‐extrinsic regulators of function can predispose to autoimmunity.
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Affiliation(s)
- Myoungsun Son
- The Feinstein Institute for Medical Research, Center for Autoimmune and Musculoskeletal Diseases, Manhasset, NY, USA
| | - Sun Jung Kim
- The Feinstein Institute for Medical Research, Center for Autoimmune and Musculoskeletal Diseases, Manhasset, NY, USA
| | - Betty Diamond
- The Feinstein Institute for Medical Research, Center for Autoimmune and Musculoskeletal Diseases, Manhasset, NY, USA
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102
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Class II major histocompatibility complex mutant mice to study the germ-line bias of T-cell antigen receptors. Proc Natl Acad Sci U S A 2016; 113:E5608-17. [PMID: 27588903 DOI: 10.1073/pnas.1609717113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The interaction of αβ T-cell antigen receptors (TCRs) with peptides bound to MHC molecules lies at the center of adaptive immunity. Whether TCRs have evolved to react with MHC or, instead, processes in the thymus involving coreceptors and other molecules select MHC-specific TCRs de novo from a random repertoire is a longstanding immunological question. Here, using nuclease-targeted mutagenesis, we address this question in vivo by generating three independent lines of knockin mice with single-amino acid mutations of conserved class II MHC amino acids that often are involved in interactions with the germ-line-encoded portions of TCRs. Although the TCR repertoire generated in these mutants is similar in size and diversity to that in WT mice, the evolutionary bias of TCRs for MHC is suggested by a shift and preferential use of some TCR subfamilies over others in mice expressing the mutant class II MHCs. Furthermore, T cells educated on these mutant MHC molecules are alloreactive to each other and to WT cells, and vice versa, suggesting strong functional differences among these repertoires. Taken together, these results highlight both the flexibility of thymic selection and the evolutionary bias of TCRs for MHC.
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103
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Liu H, Jain R, Guan J, Vuong V, Ishido S, La Gruta NL, Gray DH, Villadangos JA, Mintern JD. Ubiquitin ligase MARCH 8 cooperates with CD83 to control surface MHC II expression in thymic epithelium and CD4 T cell selection. J Exp Med 2016; 213:1695-703. [PMID: 27503069 PMCID: PMC4995085 DOI: 10.1084/jem.20160312] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 06/28/2016] [Indexed: 11/09/2022] Open
Abstract
Major histocompatibility complex class II (MHC II) expression is tightly regulated, being subjected to cell type-specific mechanisms that closely control its levels at the cell surface. Ubiquitination by the E3 ubiquitin ligase MARCH 1 regulates MHC II expression in dendritic cells and B cells. In this study, we demonstrate that the related ligase MARCH 8 is responsible for regulating surface MHC II in thymic epithelial cells (TECs). March8(-/-) mice have elevated MHC II at the surface of cortical TECs and autoimmune regulator (AIRE)(-) medullary TECs (mTECs), but not AIRE(+) mTECs. Despite this, thymic and splenic CD4(+) T cell numbers and repertoires remained unaltered in March8(-/-) mice. Notably, the ubiquitination of MHC II by MARCH 8 is controlled by CD83. Mice expressing a mutated form of CD83 (Cd83(anu/anu) mice) have impaired CD4(+) T cell selection, but deleting March8 in Cd83(anu/anu) mice restored CD4(+) T cell selection to normal levels. Therefore, orchestrated regulation of MHC II surface expression in TECs by MARCH 8 and CD83 plays a major role in CD4(+) T cell selection. Our results also highlight the specialized use of ubiquitinating machinery in distinct antigen-presenting cell types, with important functional consequences and implications for therapeutic manipulation.
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Affiliation(s)
- Haiyin Liu
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Reema Jain
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3010, Australia The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Jing Guan
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3010, Australia Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Vivian Vuong
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Satoshi Ishido
- Laboratory of Integrative Infection Immunity, Showa Pharmaceutical University, Machida, Tokyo 194-0042, Japan Department of Microbiology, Hyogo College of Medicine, Hyogo 663-8131, Japan
| | - Nicole L La Gruta
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3010, Australia Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Daniel H Gray
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3010, Australia The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Jose A Villadangos
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Justine D Mintern
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
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104
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Vaidya HJ, Briones Leon A, Blackburn CC. FOXN1 in thymus organogenesis and development. Eur J Immunol 2016; 46:1826-37. [PMID: 27378598 PMCID: PMC4988515 DOI: 10.1002/eji.201545814] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 06/21/2016] [Accepted: 06/29/2016] [Indexed: 01/11/2023]
Abstract
Development of the primary T-cell repertoire takes place in the thymus. The linked processes of T-cell differentiation and T-cell repertoire selection each depend on interactions between thymocytes and thymic stromal cells; in particular, with the epithelial cells of the cortical and medullary thymic compartments (cortical and medullary thymic epithelial cells; cTECs and mTECs, respectively). The importance of the thymic epithelial cell lineage in these processes was revealed in part through analysis of nude (nu/nu) mice, which are congenitally hairless and athymic. The nude phenotype results from null mutation of the forkhead transcription factor FOXN1, which has emerged as a pivotal regulator both of thymus development and homeostasis. FOXN1 has been shown to play critical roles in thymus development, function, maintenance, and even regeneration, which positions it as a master regulator of thymic epithelial cell (TEC) differentiation. In this review, we discuss current understanding of the regulation and functions of FOXN1 throughout thymus ontogeny, from the earliest stages of organogenesis through homeostasis to age-related involution, contextualising its significance through reference to other members of the wider Forkhead family.
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Affiliation(s)
- Harsh Jayesh Vaidya
- MRC Centre for Regenerative MedicineInstitute for Stem Cell ResearchSchool of Biological SciencesEdinburghUK
| | - Alberto Briones Leon
- MRC Centre for Regenerative MedicineInstitute for Stem Cell ResearchSchool of Biological SciencesEdinburghUK
| | - C. Clare Blackburn
- MRC Centre for Regenerative MedicineInstitute for Stem Cell ResearchSchool of Biological SciencesEdinburghUK
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105
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Sadegh-Nasseri S. A step-by-step overview of the dynamic process of epitope selection by major histocompatibility complex class II for presentation to helper T cells. F1000Res 2016; 5. [PMID: 27347387 PMCID: PMC4902097 DOI: 10.12688/f1000research.7664.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/27/2016] [Indexed: 11/25/2022] Open
Abstract
T cell antigen receptors (TCRs) expressed on cytotoxic or helper T cells can only see their specific target antigen as short sequences of peptides bound to the groove of proteins of major histocompatibility complex (MHC) class I, and class II respectively. In addition to the many steps, several participating proteins, and multiple cellular compartments involved in the processing of antigens, the MHC structure, with its dynamic and flexible groove, has perfectly evolved as the underlying instrument for epitope selection. In this review, I have taken a step-by-step, and rather historical, view to describe antigen processing and determinant selection, as we understand it today, all based on decades of intense research by hundreds of laboratories.
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106
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Lai ZW, Weisser J, Nilse L, Costa F, Keller E, Tholen M, Kizhakkedathu JN, Biniossek M, Bronsert P, Schilling O. Formalin-Fixed, Paraffin-Embedded Tissues (FFPE) as a Robust Source for the Profiling of Native and Protease-Generated Protein Amino Termini. Mol Cell Proteomics 2016; 15:2203-13. [PMID: 27087653 PMCID: PMC5083106 DOI: 10.1074/mcp.o115.056515] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 04/12/2016] [Indexed: 11/06/2022] Open
Abstract
Dysregulated proteolysis represents a hallmark of numerous diseases. In recent years, increasing number of studies has begun looking at the protein termini in hope to unveil the physiological and pathological functions of proteases in clinical research. However, the availability of cryopreserved tissue specimens is often limited. Alternatively, formalin-fixed, paraffin-embedded (FFPE) tissues offer an invaluable resource for clinical research. Pathologically relevant tissues are often stored as FFPE, which represent the most abundant resource of archived human specimens. In this study, we established a robust workflow to investigate native and protease-generated protein N termini from FFPE specimens. We demonstrate comparable N-terminomes of cryopreserved and formalin-fixed tissue, thereby showing that formalin fixation/paraffin embedment does not proteolytically damage proteins. Accordingly, FFPE specimens are fully amenable to N-terminal analysis. Moreover, we demonstrate feasibility of FFPE-degradomics in a quantitative N-terminomic study of FFPE liver specimens from cathepsin L deficient or wild-type mice. Using a machine learning approach in combination with the previously determined cathepsin L specificity, we successfully identify a number of potential cathepsin L cleavage sites. Our study establishes FFPE specimens as a valuable alternative to cryopreserved tissues for degradomic studies.
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Affiliation(s)
- Zon Weng Lai
- From the ‡Institute of Molecular Medicine and Cell Research
| | | | - Lars Nilse
- From the ‡Institute of Molecular Medicine and Cell Research
| | | | - Eva Keller
- From the ‡Institute of Molecular Medicine and Cell Research
| | - Martina Tholen
- From the ‡Institute of Molecular Medicine and Cell Research
| | - Jayachandran N Kizhakkedathu
- ¶Department of Pathology and Laboratory Medicine and Department of Chemistry, Centre of Chemistry, University of British Columbia, Vancouver, Canada
| | | | - Peter Bronsert
- ‖Department of Pathology, **German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Oliver Schilling
- From the ‡Institute of Molecular Medicine and Cell Research, **German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany ‡‡BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany;
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107
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Öhrvik H, Logeman B, Turk B, Reinheckel T, Thiele DJ. Cathepsin Protease Controls Copper and Cisplatin Accumulation via Cleavage of the Ctr1 Metal-binding Ectodomain. J Biol Chem 2016; 291:13905-13916. [PMID: 27143361 DOI: 10.1074/jbc.m116.731281] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Indexed: 11/06/2022] Open
Abstract
Copper is an essential metal ion for embryonic development, iron acquisition, cardiac function, neuropeptide biogenesis, and other critical physiological processes. Ctr1 is a high affinity Cu(+) transporter on the plasma membrane and endosomes that exists as a full-length protein and a truncated form of Ctr1 lacking the methionine- and histidine-rich metal-binding ectodomain, and it exhibits reduced Cu(+) transport activity. Here, we identify the cathepsin L/B endolysosomal proteases functioning in a direct and rate-limiting step in the Ctr1 ectodomain cleavage. Cells and mice lacking cathepsin L accumulate full-length Ctr1 and hyper-accumulate copper. As Ctr1 also transports the chemotherapeutic drug cisplatin via direct binding to the ectodomain, we demonstrate that the combination of cisplatin with a cathepsin L/B inhibitor enhances cisplatin uptake and cell killing. These studies identify a new processing event and the key protease that cleaves the Ctr1 metal-binding ectodomain, which functions to regulate cellular Cu(+) and cisplatin acquisition.
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Affiliation(s)
- Helena Öhrvik
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina 27710.
| | - Brandon Logeman
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina 27710
| | - Boris Turk
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, SI-1000 Ljubljana, Slovenia; Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Thomas Reinheckel
- Institute of Molecular Medicine and Cell Research, Medical Faculty, Freiburg 79104 Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg 79104 Germany
| | - Dennis J Thiele
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina 27710; Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina 27710; Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina 27710.
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108
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Perry JSA, Hsieh CS. Development of T-cell tolerance utilizes both cell-autonomous and cooperative presentation of self-antigen. Immunol Rev 2016; 271:141-55. [PMID: 27088912 PMCID: PMC4837647 DOI: 10.1111/imr.12403] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The development of T-cell self-tolerance in the thymus is important for establishing immune homeostasis and preventing autoimmunity. Here, we review the components of T-cell tolerance, which includes T-cell receptor (TCR) self-reactivity, costimulation, cytokines, and antigen presentation by a variety of antigen-presenting cells (APCs) subsets. We discuss the current evidence on the process of regulatory T (Treg) cell and negative selection and the importance of TCR signaling. We then examine recent evidence showing unique roles for bone marrow (BM)-derived APCs and medullary thymic epithelial cells (mTECs) on the conventional and Treg TCR repertoire, as well as emerging data on the role of B cells in tolerance. Finally, we review the accumulating data that suggest that cooperative antigen presentation is a prominent component of T -ell tolerance. With the development of tools to interrogate the function of individual APC subsets in the medulla, we have gained greater understanding of the complex cellular and molecular events that determine T-cell tolerance.
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Affiliation(s)
- Justin S A Perry
- Department of Internal Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Chyi-Song Hsieh
- Department of Internal Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, 63110, USA
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109
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Wilkinson RDA, Young A, Burden RE, Williams R, Scott CJ. A bioavailable cathepsin S nitrile inhibitor abrogates tumor development. Mol Cancer 2016; 15:29. [PMID: 27097645 PMCID: PMC4839156 DOI: 10.1186/s12943-016-0513-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 04/09/2016] [Indexed: 12/27/2022] Open
Abstract
Background Cathepsin S has been implicated in a variety of malignancies with genetic ablation studies demonstrating a key role in tumor invasion and neo-angiogenesis. Thus, the application of cathepsin S inhibitors may have clinical utility in the treatment of cancer. In this investigation, we applied a cell-permeable dipeptidyl nitrile inhibitor of cathepsin S, originally developed to target cathepsin S in inflammatory diseases, in both in vitro and in vivo tumor models. Methods Validation of cathepsin S selectivity was carried out by assaying fluorogenic substrate turnover using recombinant cathepsin protease. Complete kinetic analysis was carried out and true Ki values calculated. Abrogation of tumour invasion using murine MC38 and human MCF7 cell lines were carried out in vitro using a transwell migration assay. Effect on endothelial tube formation was evaluated using primary HUVEC cells. The effect of inhibitor in vivo on MC38 and MCF7 tumor progression was evaluated using cells propagated in C57BL/6 and BALB/c mice respectively. Subsequent immunohistochemical staining of proliferation (Ki67) and apoptosis (TUNEL) was carried out on MCF7 tumors. Results We confirmed that this inhibitor was able to selectively target cathepsin S over family members K, V, L and B. The inhibitor also significantly reduced MC38 and MCF7 cell invasion and furthermore, significantly reduced HUVEC endothelial tubule formation in vitro. In vivo analysis revealed that the compound could significantly reduce tumor volume in murine MC38 syngeneic and MCF7 xenograft models. Immunohistochemical analysis of MCF7 tumors revealed cathepsin S inhibitor treatment significantly reduced proliferation and increased apoptosis. Conclusions In summary, these results highlight the characterisation of this nitrile cathepsin S inhibitor using in vitro and in vivo tumor models, presenting a compound which may be used to further dissect the role of cathepsin S in cancer progression and may hold therapeutic potential. Electronic supplementary material The online version of this article (doi:10.1186/s12943-016-0513-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard D A Wilkinson
- Molecular Therapeutics, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom
| | - Andrew Young
- Molecular Therapeutics, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom
| | - Roberta E Burden
- Molecular Therapeutics, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom
| | - Rich Williams
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom.
| | - Christopher J Scott
- Molecular Therapeutics, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom.
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110
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Ohigashi I, Kozai M, Takahama Y. Development and developmental potential of cortical thymic epithelial cells. Immunol Rev 2016; 271:10-22. [DOI: 10.1111/imr.12404] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Izumi Ohigashi
- Division of Experimental Immunology; Institute for Genome Research; University of Tokushima; Tokushima Japan
| | - Mina Kozai
- Division of Experimental Immunology; Institute for Genome Research; University of Tokushima; Tokushima Japan
| | - Yousuke Takahama
- Division of Experimental Immunology; Institute for Genome Research; University of Tokushima; Tokushima Japan
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111
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Schröder B. The multifaceted roles of the invariant chain CD74--More than just a chaperone. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:1269-81. [PMID: 27033518 DOI: 10.1016/j.bbamcr.2016.03.026] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 01/13/2023]
Abstract
The invariant chain (CD74) is well known for its essential role in antigen presentation by mediating assembly and subcellular trafficking of the MHCII complex. Beyond this, CD74 has also been implicated in a number of processes independent of MHCII. These include the regulation of endosomal trafficking, cell migration and cellular signalling as surface receptor of the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF). In several forms of cancer, CD74 is up-regulated and associated with enhanced proliferation and metastatic potential. In this review, an overview of the diverse biological functions of the CD74 protein is provided with a particular focus on how these may be regulated. In particular, proteolysis of CD74 will be discussed as a central mechanism to control the actions of this important protein at different levels.
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Affiliation(s)
- Bernd Schröder
- Biochemical Institute, Christian Albrechts University of Kiel, Otto-Hahn-Platz 9, D-24118 Kiel, Germany.
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112
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Xue T, Liu P, Zhou Y, Liu K, Yang L, Moritz RL, Yan W, Xu LX. Interleukin-6 Induced "Acute" Phenotypic Microenvironment Promotes Th1 Anti-Tumor Immunity in Cryo-Thermal Therapy Revealed By Shotgun and Parallel Reaction Monitoring Proteomics. Am J Cancer Res 2016; 6:773-94. [PMID: 27162549 PMCID: PMC4860887 DOI: 10.7150/thno.14394] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 02/08/2016] [Indexed: 12/14/2022] Open
Abstract
Cryo-thermal therapy has been emerged as a promising novel therapeutic strategy for advanced breast cancer, triggering higher incidence of tumor regression and enhanced remission of metastasis than routine treatments. To better understand its anti-tumor mechanism, we utilized a spontaneous metastatic mouse model and quantitative proteomics to compare N-glycoproteome changes in 94 serum samples with and without treatment. We quantified 231 highly confident N-glycosylated proteins using iTRAQ shotgun proteomics. Among them, 53 showed significantly discriminated regulatory patterns over the time course, in which the acute phase response emerged as the most enhanced pathway. The anti-tumor feature of the acute response was further investigated using parallel reaction monitoring target proteomics and flow cytometry on 23 of the 53 significant proteins. We found that cryo-thermal therapy reset the tumor chronic inflammation to an “acute” phenotype, with up-regulation of acute phase proteins including IL-6 as a key regulator. The IL-6 mediated “acute” phenotype transformed IL-4 and Treg-promoting ICOSL expression to Th1-promoting IFN-γ and IL-12 production, augmented complement system activation and CD86+MHCII+ dendritic cells maturation and enhanced the proliferation of Th1 memory cells. In addition, we found an increased production of tumor progression and metastatic inhibitory proteins under such “acute” environment, favoring the anti-metastatic effect. Moreover, cryo-thermal on tumors induced the strongest “acute” response compared to cryo/hyperthermia alone or cryo-thermal on healthy tissues, accompanying by the most pronounced anti-tumor immunological effect. In summary, we demonstrated that cryo-thermal therapy induced, IL-6 mediated “acute” microenvironment shifted the tumor chronic microenvironment from Th2 immunosuppressive and pro-tumorigenic to Th1 immunostimulatory and tumoricidal state. Moreover, the magnitude of “acute” and “danger” signals play a key role in determining the efficacy of anti-tumor activity.
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113
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Nitta T, Suzuki H. Thymic stromal cell subsets for T cell development. Cell Mol Life Sci 2016; 73:1021-37. [PMID: 26825337 PMCID: PMC11108406 DOI: 10.1007/s00018-015-2107-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/26/2015] [Accepted: 12/01/2015] [Indexed: 12/20/2022]
Abstract
The thymus provides a specialized microenvironment in which a variety of stromal cells of both hematopoietic and non-hematopoietic origin regulate development and repertoire selection of T cells. Recent studies have been unraveling the inter- and intracellular signals and transcriptional networks for spatiotemporal regulation of development of thymic stromal cells, mainly thymic epithelial cells (TECs), and the molecular mechanisms of how different TEC subsets control T cell development and selection. TECs are classified into two functionally different subsets: cortical TECs (cTECs) and medullary TECs (mTECs). cTECs induce positive selection of diverse and functionally distinct T cells by virtue of unique antigen-processing systems, while mTECs are essential for establishing T cell tolerance via ectopic expression of peripheral tissue-restricted antigens and cooperation with dendritic cells. In addition to reviewing the role of the thymic stroma in conventional T cell development, we will discuss recently discovered novel functions of TECs in the development of unconventional T cells, such as natural killer T cells and γδT cells.
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Affiliation(s)
- Takeshi Nitta
- Department of Immunology and Pathology, Research Institute, National Center for Global Health and Medicine, Chiba, 272-8516, Japan.
| | - Harumi Suzuki
- Department of Immunology and Pathology, Research Institute, National Center for Global Health and Medicine, Chiba, 272-8516, Japan.
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114
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Yang J, Liu H, Zheng G, Xiang X, Lv Z, Wang T. Cathepsin L of the sea cucumber Apostichopus japonicus-molecular characterization and transcriptional response to Vibrio splendidus infection. FISH & SHELLFISH IMMUNOLOGY 2016; 49:387-395. [PMID: 26777896 DOI: 10.1016/j.fsi.2016.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/04/2016] [Accepted: 01/07/2016] [Indexed: 06/05/2023]
Abstract
Cathepsin L, a lysosomal endopeptidase, has been noted for its involvement in the innate immune response in invertebrates. Here, the cathepsin L cDNA of the sea cucumber Apostichopus japonicus (AjCatL) is identified from an EST library and then cloned by the rapid amplification of the cDNA ends (RACE) PCR. The full-length cDNA is 1678 bp long containing an open reading frame (ORF) of 1002 bp, an 80 bp 5' UTR and a 599 bp 3' UTR. The cDNA encodes 333 amino acid residues with a predicted molecular mass of 37.07 kDa and a theoretical isoelectric point (pI) of 5.01. The full-length AjCatL contains three active sites of eukaryotic thiol (cysteine) protease at positions 133-144, 278-288 and 295-314. Analysis of the predicted tertiary structure of prepro-CatL (17-333 aa) and mature-CatL (116-333 aa) reveals that the propeptide region (17-115 aa) blocks access to the substrate-binding cleft. Phylogenetic analysis shows that the AjCatL is clustered together with two other CatLs from Strongylocentrotus purpuratus. The enzymatic activity of AjCatL was verified using a substrate hydrolyzing assay with recombinant mAjCatL. Further analysis of real time-PCR demonstrates that the expression of AjCatL mRNA is significantly up-regulated in the coelomocytes in cases of infection with the common bacterial pathogen, Vibrio splendidus. This suggests that the AjCatL is likely to be involved in the immune response.
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Affiliation(s)
- Jingwen Yang
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Sciences, Zhejiang Ocean University, Zhoushan, Zhejiang, 316022, China
| | - Huihui Liu
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Sciences, Zhejiang Ocean University, Zhoushan, Zhejiang, 316022, China
| | - Gang Zheng
- Ocean Research Center of Zhoushan, Zhejiang University, Zhoushan, Zhejiang, 316021, China
| | - Xiaowei Xiang
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Sciences, Zhejiang Ocean University, Zhoushan, Zhejiang, 316022, China
| | - Zhenming Lv
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Sciences, Zhejiang Ocean University, Zhoushan, Zhejiang, 316022, China.
| | - Tianming Wang
- National Engineering Research Center of Marine Facilities Aquaculture, College of Marine Sciences, Zhejiang Ocean University, Zhoushan, Zhejiang, 316022, China.
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115
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Ao J, Li Q, Yang Z, Mu Y. A cystatin F homologue from large yellow croaker (Larimichthys crocea) inhibits activity of multiple cysteine proteinases and Ii chain processing in vitro. FISH & SHELLFISH IMMUNOLOGY 2016; 48:62-70. [PMID: 26578250 DOI: 10.1016/j.fsi.2015.11.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 06/05/2023]
Abstract
Cystatin F, a member of the family II cystatins, plays important roles in immune response-related processes through inhibiting specific enzyme targets. In this study, a cystatin F homologue, LycCysF, was identified and characterized from large yellow croaker (Larimichthys crocea). The deduced LycCysF protein exhibits a typical structural feature of type II cystatins, including three evolutionally conserved motifs, Gly(35), QVVRG(79-83) and PW(130-131). Tissue expression analysis showed that LycCysF mRNA was expressed in all tissues examined, albeit at different levels. Recombinant LycCysF (rLycCysF) produced in Pichia pastoris could inhibit the activity of multiple cysteine proteases, including papain, legumain and recombinant large yellow croaker cathepsin B, L and S. Moreover, rLycCysF could inhibit the Ii chain processing by recombinant cathepsin S in vitro. These data suggest that LycCysF may participate in regulation of cathepsins and MHC-II associated Ii chain processing. In addition, mammalian cystatin F is produced as an inactive dimer, becoming activated by proteolysis in the endo/lysosome of immune cells and then exerts its function of regulating downstream proteases activity. However, the N-terminal extension and two additional cysteine residues responsible for dimer formation are absent in LycCysF and cystatin F from other fish species, reptiles and Aves, indicating that these proteins can not form dimer and may regulate the proteases activity via an alternate pathway distinct from mammalian cystatin F. To our knowledge, this is the first report on molecular characteristics of a teleost cystatin F and its role in Ii chain processing.
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Affiliation(s)
- Jingqun Ao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China.
| | - Qiuhua Li
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Zhijun Yang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Yinnan Mu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
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Li Q, Ao J, Mu Y, Yang Z, Li T, Zhang X, Chen X. Cathepsin S, but not cathepsin L, participates in the MHC class II-associated invariant chain processing in large yellow croaker (Larimichthys crocea). FISH & SHELLFISH IMMUNOLOGY 2015; 47:743-50. [PMID: 26475363 DOI: 10.1016/j.fsi.2015.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/05/2015] [Accepted: 10/09/2015] [Indexed: 05/28/2023]
Abstract
Two cysteine proteases, cathepsin S (CatS) and cathepsin L (CatL), have been identified as the key enzymes involved in the processing of invariant chain (Ii chain) in mammals. However, little is known about the roles of fish cathepsins in the Ii chain processing. In this study, large yellow croaker cathepsin S (LycCatS) and L (LycCatL) were identified and characterized. Based on the sequence comparison and phylogenetic analysis, both LycCatS and LycCatL are highly conserved to their counterparts in teleost. These two cathepsins were constitutively expressed in all tissues and immune-related cells tested, although at different levels. Both recombinant LycCatS (rLycCatS) and LycCatL (rLycCatL) possess the typical cysteine protease activity. Like other mammalian endopeptidase cathepsins, rLycCatS and rLycCatL could be autocatalytically activated to remove propeptides and release active mature peptides. On the other hand, the autocatalytic activation of rLycCatL could be inhibited by recombinant large yellow croaker Ii chain (rLyc-TR-Ii), but the autocatalytic activation of rLycCatS was not affected by rLyc-TR-Ii. Furthermore, the activated rLycCatS can efficiently process rLyc-TR-Ii in a stepwise manner in vitro, while the activated rLycCatL can not. These data indicate that cathepsin S may be the main cathepsin involved in the Ii chain processing in bony fish.
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Affiliation(s)
- Qiuhua Li
- School of Marine Sciences, Ningbo University, Ningbo 315211, China; Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
| | - Jingqun Ao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China.
| | - Yinnan Mu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
| | - Zhijun Yang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
| | - Ting Li
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
| | - Xin Zhang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; South China Sea Bio-Resource Exploration and Utilization Collaborative Innovation Center, Xiamen 361005, China
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117
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The Potential Role of the Proteases Cathepsin D and Cathepsin L in the Progression and Metastasis of Epithelial Ovarian Cancer. Biomolecules 2015; 5:3260-79. [PMID: 26610586 PMCID: PMC4693277 DOI: 10.3390/biom5043260] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/13/2015] [Indexed: 02/08/2023] Open
Abstract
Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancies and has a poor prognosis due to relatively unspecific early symptoms, and thus often advanced stage, metastasized cancer at presentation. Metastasis of EOC occurs primarily through the transcoelomic route whereby exfoliated tumor cells disseminate within the abdominal cavity, particularly to the omentum. Primary and metastatic tumor growth requires a pool of proangiogenic factors in the microenvironment which propagate new vasculature in the growing cancer. Recent evidence suggests that proangiogenic factors other than the widely known, potent angiogenic factor vascular endothelial growth factor may mediate growth and metastasis of ovarian cancer. In this review we examine the role of some of these alternative factors, specifically cathepsin D and cathepsin L.
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Korenč M, Lenarčič B, Novinec M. Human cathepsin L, a papain-like collagenase without proline specificity. FEBS J 2015; 282:4328-40. [PMID: 26306868 DOI: 10.1111/febs.13499] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/13/2015] [Accepted: 08/21/2015] [Indexed: 12/01/2022]
Abstract
Several members of the papain-like peptidase family have the ability to degrade collagen molecules by cleaving within the triple helix region of this difficult substrate. A common denominator of these peptidases is their ability to cleave substrates with Pro in the P2 position. In humans, cathepsin K is the best-known papain-like collagenase. Here, we investigate the collagenolytic activity of human cathepsin L, which is closely related to cathepsin K. We show that, despite lacking proline specificity, cathepsin L efficiently cleaves type I collagen within the triple helix region and produces a cleavage pattern similar to that of cathepsin K. We demonstrate that both enzymes have similar affinities for type I collagen and are able to release proteolytic fragments from insoluble collagen. Moreover, cathepsin K is only approximately fourfold more potent than cathepsin L in releasing fragments from reconstituted fibrils of FITC-labeled collagen. Replacing active site residues of cathepsin L with those from cathepsin K introduces cathepsin K-like specificity towards synthetic substrates and increases the collagenolytic activity of cathepsin L. Replacing three residues in the S2 subsite is sufficient to produce a mutant with collagenolytic activity on par with human cathepsin K. These results provide a basis for engineering collagenolytic activity into non-collagenolytic papain-like scaffolds.
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Affiliation(s)
- Matevž Korenč
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
| | - Brigita Lenarčič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia.,Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Marko Novinec
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
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119
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Sadegh-Nasseri S, Kim A. MHC Class II Auto-Antigen Presentation is Unconventional. Front Immunol 2015; 6:372. [PMID: 26257739 PMCID: PMC4510428 DOI: 10.3389/fimmu.2015.00372] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/06/2015] [Indexed: 01/09/2023] Open
Abstract
Antigen presentation is highly critical in adoptive immunity. Only by interacting with antigens presented by major histocompatibility complex class II molecules, helper T cells can be stimulated to fight infections or diseases. The degradation of a full protein into small peptide fragments bound to class II molecules is a dynamic, lengthy process consisting of many steps and chaperons. Deregulation in any step of antigen processing could lead to the development of self-reactive T cells or defective immune response to pathogens. Indeed, human leukocyte antigens class II genes are the predominant contributors to susceptibility to autoimmune diseases. Conventional antigen-processing calls for internalization of extracellular antigens followed by processing and epitope selection within antigen-processing subcellular compartments, enriched with all necessary accessory molecules, processing enzymes, and proper pH and denaturing conditions. However, recent data examining the temporal relationship between antigen uptakes, processing, and epitope selection revealed unexpected characteristics for auto-antigenic epitopes, which were not shared with antigenic epitopes from pathogens. This review provides a discussion of the relevance of these findings to the mechanisms of autoimmunity.
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Affiliation(s)
| | - AeRyon Kim
- Department of Pathology, Johns Hopkins School of Medicine , Baltimore, MD , USA
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120
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Orlowski GM, Colbert JD, Sharma S, Bogyo M, Robertson SA, Rock KL. Multiple Cathepsins Promote Pro-IL-1β Synthesis and NLRP3-Mediated IL-1β Activation. THE JOURNAL OF IMMUNOLOGY 2015. [PMID: 26195813 DOI: 10.4049/jimmunol.1500509] [Citation(s) in RCA: 180] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sterile particles induce robust inflammatory responses that underlie the pathogenesis of diseases like silicosis, gout, and atherosclerosis. A key cytokine mediating this response is IL-1β. The generation of bioactive IL-1β by sterile particles is mediated by the NOD-like receptor containing a pyrin domain 3 (NLRP3) inflammasome, although exactly how this occurs is incompletely resolved. Prior studies have found that the cathepsin B inhibitor, Ca074Me, suppresses this response, supporting a model whereby ingested particles disrupt lysosomes and release cathepsin B into the cytosol, somehow activating NLRP3. However, reports that cathepsin B-deficient macrophages have no defect in particle-induced IL-1β generation have questioned cathepsin B's involvement. In this study, we examine the hypothesis that multiple redundant cathepsins (not just cathepsin B) mediate this process by evaluating IL-1β generation in murine macrophages, singly or multiply deficient in cathepsins B, L, C, S and X. Using an activity-based probe, we measure specific cathepsin activity in living cells, documenting compensatory changes in cathepsin-deficient cells, and Ca074Me's dose-dependent cathepsin inhibition profile is analyzed in parallel with its suppression of particle-induced IL-1β secretion. Also, we evaluate endogenous cathepsin inhibitors cystatins C and B. Surprisingly, we find that multiple redundant cathepsins, inhibited by Ca074Me and cystatins, promote pro-IL-1β synthesis, and to our knowledge, we provide the first evidence that cathepsin X plays a nonredundant role in nonparticulate NLRP3 activation. Finally, we find cathepsin inhibitors selectively block particle-induced NLRP3 activation, independently of suppressing pro-IL-1β synthesis. Altogether, we demonstrate that both small molecule and endogenous cathepsin inhibitors suppress particle-induced IL-1β secretion, implicating roles for multiple cathepsins in both pro-IL-1β synthesis and NLRP3 activation.
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Affiliation(s)
- Gregory M Orlowski
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Jeff D Colbert
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Shruti Sharma
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655
| | - Matthew Bogyo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305; and
| | - Stephanie A Robertson
- Sandler Center for Drug Discovery, University of California, San Francisco, San Francisco, CA 94158
| | - Kenneth L Rock
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655;
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121
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Allan ERO, Yates RM. Redundancy between Cysteine Cathepsins in Murine Experimental Autoimmune Encephalomyelitis. PLoS One 2015; 10:e0128945. [PMID: 26075905 PMCID: PMC4468166 DOI: 10.1371/journal.pone.0128945] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/01/2015] [Indexed: 11/18/2022] Open
Abstract
The cysteine cathepsins B, S, and L are functionally linked to antigen processing, and hence to autoimmune disorders such as multiple sclerosis. Stemming from several studies that demonstrate that mice can be protected from experimental autoimmune encephalomyelitis (EAE) through the pharmacologic inhibition of cysteine cathepsins, it has been suggested that targeting these enzymes in multiple sclerosis may be of therapeutic benefit. Utilizing mice deficient in cysteine cathepsins both individually and in combination, we found that the myelin-associated antigen myelin oligodendrocyte glycoprotein (MOG) was efficiently processed and presented by macrophages to CD4+ T cells in the individual absence of cathepsin B, S or L. Similarly, mice deficient in cathepsin B or S were susceptible to MOG-induced EAE and displayed clinical progression and immune infiltration into the CNS, similar to their wild-type counterparts. Owing to a previously described CD4+ T cell deficiency in mice deficient in cathepsin L, such mice were protected from EAE. When multiple cysteine cathepsins were simultaneously inhibited via genetic deletion of both cathepsins B and S, or by a cathepsin inhibitor (LHVS), MHC-II surface expression, MOG antigen presentation and EAE were attenuated or prevented. This study demonstrates the functional redundancy between cathepsin B, S and L in EAE, and suggests that the inhibition of multiple cysteine cathepsins may be needed to modulate autoimmune disorders such as multiple sclerosis.
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Affiliation(s)
- Euan Ramsay Orr Allan
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Alberta, Canada
| | - Robin Michael Yates
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Alberta, Canada
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, Alberta, Canada
- * E-mail:
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122
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Weitoft T, Larsson A, Manivel VA, Lysholm J, Knight A, Rönnelid J. Cathepsin S and cathepsin L in serum and synovial fluid in rheumatoid arthritis with and without autoantibodies. Rheumatology (Oxford) 2015; 54:1923-8. [DOI: 10.1093/rheumatology/keu486] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Indexed: 11/13/2022] Open
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123
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Wang F, Muller S. Manipulating autophagic processes in autoimmune diseases: a special focus on modulating chaperone-mediated autophagy, an emerging therapeutic target. Front Immunol 2015; 6:252. [PMID: 26042127 PMCID: PMC4437184 DOI: 10.3389/fimmu.2015.00252] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/07/2015] [Indexed: 12/14/2022] Open
Abstract
Autophagy, a constitutive intracellular degradation pathway, displays essential role in the homeostasis of immune cells, antigen processing and presentation, and many other immune processes. Perturbation of autophagy has been shown to be related to several autoimmune syndromes, including systemic lupus erythematosus. Therefore, modulating autophagy processes appears most promising for therapy of such autoimmune diseases. Autophagy can be said non-selective or selective; it is classified into three main forms, namely macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA), the former process being by far the most intensively investigated. The role of CMA remains largely underappreciated in autoimmune diseases, even though CMA has been claimed to play pivotal functions into major histocompatibility complex class II-mediated antigen processing and presentation. Therefore, hereby, we give a special focus on CMA as a therapeutic target in autoimmune diseases, based in particular on our most recent experimental results where a phosphopeptide modulates lupus disease by interacting with CMA regulators. We propose that specifically targeting lysosomes and lysosomal pathways, which are central in autophagy processes and seem to be altered in certain autoimmune diseases such as lupus, could be an innovative approach of efficient and personalized treatment.
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Affiliation(s)
- Fengjuan Wang
- Immunopathology and Therapeutic Chemistry/Laboratory of Excellence MEDALIS, CNRS, Institut de Biologie Moléculaire et Cellulaire , Strasbourg , France
| | - Sylviane Muller
- Immunopathology and Therapeutic Chemistry/Laboratory of Excellence MEDALIS, CNRS, Institut de Biologie Moléculaire et Cellulaire , Strasbourg , France ; University of Strasbourg Institute for Advanced Study , Strasbourg , France
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124
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Hennies CM, Lehn MA, Janssen EM. Quantitating MHC class II trafficking in primary dendritic cells using imaging flow cytometry. J Immunol Methods 2015; 423:18-28. [PMID: 25967952 DOI: 10.1016/j.jim.2015.04.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 04/24/2015] [Accepted: 04/30/2015] [Indexed: 01/24/2023]
Abstract
Presentation of antigenic peptides in MHC class II (MHCII) on dendritic cells (DCs) is the first step in the activation of antigen-specific CD4(+)T cells. The expression of surface MHCII-peptide complexes is tightly regulated as the frequency of MHCII-peptide complexes can affect the magnitude, as well as the phenotype of the ensuing CD4(+)T cell response. The surface MHCII-peptide levels are determined by the balance between expression of newly generated complexes, complex internalization, and their subsequent re-emergence or degradation. However, the molecular mechanisms that underpin these processes are still poorly understood. Here we describe a multispectral imaging flow cytometry assay to visualize MHCII trafficking that can be used as a tool to dissect the molecular mechanisms that regulate MHCII homeostasis in primary mouse and human DCs.
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Affiliation(s)
- Cassandra M Hennies
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Maria A Lehn
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Edith M Janssen
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH, USA.
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125
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Inhibins tune the thymocyte selection process by regulating thymic stromal cell differentiation. J Immunol Res 2015; 2015:837859. [PMID: 25973437 PMCID: PMC4418002 DOI: 10.1155/2015/837859] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 01/15/2015] [Accepted: 01/20/2015] [Indexed: 01/01/2023] Open
Abstract
Inhibins and Activins are members of the TGF-β superfamily that regulate the differentiation of several cell types. These ligands were initially identified as hormones that regulate the hypothalamus-pituitary-gonadal axis; however, increasing evidence has demonstrated that they are key regulators in the immune system. We have previously demonstrated that Inhibins are the main Activin ligands expressed in the murine thymus and that they regulate thymocyte differentiation, promoting the DN3-DN4 transition and the selection of SP thymocytes. As Inhibins are mainly produced by thymic stromal cells, which also express Activin receptors and Smad proteins, we hypothesized that Inhibins might play a role in stromal cell differentiation and function. Here, we demonstrate that, in the absence of Inhibins, thymic conventional dendritic cells display reduced levels of MHC Class II (MHCII) and CD86. In addition, the ratio between cTECs and mTECs was affected, indicating that mTEC differentiation was favoured and cTEC diminished in the absence of Inhibins. These changes appeared to impact thymocyte selection leading to a decreased selection of CD4SP thymocytes and increased generation of natural regulatory T cells. These findings demonstrate that Inhibins tune the T cell selection process by regulating both thymocyte and stromal cell differentiation.
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126
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Analyses of the TCR repertoire of MHC class II-restricted innate CD4⁺ T cells. Exp Mol Med 2015; 47:e154. [PMID: 25813222 PMCID: PMC4351420 DOI: 10.1038/emm.2015.7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 11/05/2014] [Accepted: 12/04/2014] [Indexed: 11/08/2022] Open
Abstract
Analysis of the T-cell receptor (TCR) repertoire of innate CD4(+) T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte-thymocyte (T-T) interaction (T-T CD4(+) T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4(+) T cells from other types of innate T cells. Using the TCR(mini) Tg mouse model, we show that the repertoire of TCRα chains in T-T CD4(+) T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRα chain sequences significantly overlapped between T-T CD4(+) T cells and conventional CD4(+) T cells in the thymus and spleen. However, the diversity of the TCRα repertoire of T-T CD4(+) T cells seemed to be restricted compared with that of conventional CD4(+) T cells. Interestingly, the frequency of the parental OT-II TCRα chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4(+) T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction.
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127
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Otomo T, Schweizer M, Kollmann K, Schumacher V, Muschol N, Tolosa E, Mittrücker HW, Braulke T. Mannose 6 phosphorylation of lysosomal enzymes controls B cell functions. J Cell Biol 2015; 208:171-80. [PMID: 25601403 PMCID: PMC4298682 DOI: 10.1083/jcb.201407077] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 12/08/2014] [Indexed: 01/25/2023] Open
Abstract
Antigen processing and presentation and cytotoxic targeting depend on the activities of several lysosomal enzymes that require mannose 6-phosphate (M6P) sorting signals for efficient intracellular transport and localization. In this paper, we show that mice deficient in the formation of M6P residues exhibit significant loss of cathepsin proteases in B cells, leading to lysosomal dysfunction with accumulation of storage material, impaired antigen processing and presentation, and subsequent defects in B cell maturation and antibody production. The targeting of lysosomal and granular enzymes lacking M6P residues is less affected in dendritic cells and T cells and sufficient for maintenance of degradative and lytic functions. M6P deficiency also impairs serum immunoglobulin levels and antibody responses to vaccination in patients. Our data demonstrate the critical role of M6P-dependent transport routes for B cell functions in vivo and humoral immunity in mice and human.
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Affiliation(s)
- Takanobu Otomo
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany Department of Pediatrics, Osaka University Graduate School of Medicine, 5650871 Suita, Osaka, Japan
| | - Michaela Schweizer
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Katrin Kollmann
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Valéa Schumacher
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Nicole Muschol
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Eva Tolosa
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Hans-Willi Mittrücker
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Thomas Braulke
- Department of Biochemistry, Children's Hospital; Department of Electron Microscopy, Center for Molecular Neurobiology; and Department of Immunology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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128
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Kim A, Sadegh-Nasseri S. Determinants of immunodominance for CD4 T cells. Curr Opin Immunol 2015; 34:9-15. [PMID: 25576665 DOI: 10.1016/j.coi.2014.12.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 12/17/2014] [Indexed: 10/24/2022]
Abstract
The term immunodominance was originally defined as a restricted T cell response to a short peptide sequence derived from a given protein. The question of what determines immunodominance has been a longstanding battle for the past two decades. Hundreds of papers have been written on different aspects of epitope selection during antigen processing documenting the complexity of the process. Antigen processing machinery involves several accessory molecules and chaperons coevolved with proteins of Major Histocompatibility Complex (MHC) molecules that each plays its part in epitope selection. These molecules are targeted to specialized vesicular compartments that also accommodate antigen processing enzymes called cathepsins. Within the antigen processing compartments, highly regulated pH gradient and reducing conditions and enzymes necessary for denaturation of the antigens are available and function to optimize processing of antigen and selection of the fittest for transport to the cell membrane and presentation to T cells. Despite the complexity, a cell free reductionist antigen processing system was recently reported that included only few purified proteins, but was shown to process and select physiologically relevant epitopes from full length protein antigens. Due to its minimalist nature the system has been quite helpful in dissecting the factors that contribute to epitope selection during antigen processing. In this review, we would summarize and highlight models that may explain how the dominant epitope may be selected for presentation to CD4(+) helper T cells.
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Affiliation(s)
- AeRyon Kim
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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129
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Azad GK, Tomar RS. Proteolytic clipping of histone tails: the emerging role of histone proteases in regulation of various biological processes. Mol Biol Rep 2015; 41:2717-30. [PMID: 24469733 DOI: 10.1007/s11033-014-3181-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Chromatin is a dynamic DNA scaffold structure that responds to a variety of external and internal stimuli to regulate the fundamental biological processes. Majority of the cases chromatin dynamicity is exhibited through chemical modifications and physical changes between DNA and histones. These modifications are reversible and complex signaling pathways involving chromatin-modifying enzymes regulate the fluidity of chromatin. Fluidity of chromatin can also be impacted through irreversible change, proteolytic processing of histones which is a poorly understood phenomenon. In recent studies, histone proteolysis has been implicated as a regulatory process involved in the permanent removal of epigenetic marks from histones. Activities responsible for clipping of histone tails and their significance in various biological processes have been observed in several organisms. Here, we have reviewed the properties of some of the known histone proteases, analyzed their significance in biological processes and have provided future directions.
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Affiliation(s)
- Gajendra Kumar Azad
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462023, India
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130
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Takada K, Takahama Y. Positive-Selection-Inducing Self-Peptides Displayed by Cortical Thymic Epithelial Cells. Adv Immunol 2015; 125:87-110. [DOI: 10.1016/bs.ai.2014.09.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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131
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Dhaenens M, Glibert P, Meert P, Vossaert L, Deforce D. Histone proteolysis: a proposal for categorization into 'clipping' and 'degradation'. Bioessays 2014; 37:70-9. [PMID: 25350939 PMCID: PMC4305269 DOI: 10.1002/bies.201400118] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We propose for the first time to divide histone proteolysis into "histone degradation" and the epigenetically connoted "histone clipping". Our initial observation is that these two different classes are very hard to distinguish both experimentally and biologically, because they can both be mediated by the same enzymes. Since the first report decades ago, proteolysis has been found in a broad spectrum of eukaryotic organisms. However, the authors often not clearly distinguish or determine whether degradation or clipping was studied. Given the importance of histone modifications in epigenetic regulation we further elaborate on the different ways in which histone proteolysis could play a role in epigenetics. Finally, unanticipated histone proteolysis has probably left a mark on many studies of histones in the past. In conclusion, we emphasize the significance of reviving the study of histone proteolysis both from a biological and an experimental perspective. Also watch the Video Abstract.
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Affiliation(s)
- Maarten Dhaenens
- Laboratory for Pharmaceutical Biotechnology, Ghent University, Ghent, Belgium
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132
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Out-of-frame start codons prevent translation of truncated nucleo-cytosolic cathepsin L in vivo. Nat Commun 2014; 5:4931. [PMID: 25222295 DOI: 10.1038/ncomms5931] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 08/07/2014] [Indexed: 11/08/2022] Open
Abstract
The lysosomal protease cathepsin L has been reported to cleave various functionally important cytosolic or nuclear proteins. To explain nucleo-cytosolic localization of cathepsin L, it has been hypothesized that skipping of the first start codon during translation initiation results in an N-terminally truncated protein lacking the endoplasmic reticulum-import signal. Here we demonstrate that out-of-frame AUGs prevent translation of truncated cathepsin L in cell culture as well as in a new knock-in mouse model. We further evaluate potential roles of nuclear cathepsin L during early embryonic development. Our analysis reveals normal epiblast development of cathepsin L-deficient embryos, but uncovers a pronounced lysosomal storage phenotype in the extra-embryonic tissue of the visceral endoderm. In conclusion, the phenotypes of cathepsin L deficiency can be fully assigned to lack of canonically targeted cathepsin L, while the biogenesis and functionality of nucleo-cytosolic cathepsin L remain elusive.
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133
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van Kasteren SI, Overkleeft HS. Endo-lysosomal proteases in antigen presentation. Curr Opin Chem Biol 2014; 23:8-15. [PMID: 25213682 DOI: 10.1016/j.cbpa.2014.08.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 08/19/2014] [Accepted: 08/20/2014] [Indexed: 02/04/2023]
Abstract
Endo-lysosomal proteases have long been attractive, yet elusive, targets for medicinal chemistry. They have found to play key roles in health and disease; with protease under- and over-activity having been implicated in cancer, osteoporosis and Alzheimer's disease. Here we will discuss their role in the adaptive immune response. The crucial roles of these enzymes multiple processes in antigen presentation will be discussed: from activating MHC-II receptors, to the production of epitopes from antigens and the activation of Toll-like receptors. The early efforts at pharmacological interventions in these pathways will also be discussed.
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Affiliation(s)
- Sander I van Kasteren
- Division of Chemical Biology, Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratory, The Netherlands.
| | - Herman S Overkleeft
- Division of Chemical Biology, Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratory, The Netherlands
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134
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135
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Halkias J, Melichar HJ, Taylor KT, Robey EA. Tracking migration during human T cell development. Cell Mol Life Sci 2014; 71:3101-17. [PMID: 24682469 PMCID: PMC11113765 DOI: 10.1007/s00018-014-1607-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 02/21/2014] [Accepted: 03/11/2014] [Indexed: 01/06/2023]
Abstract
Specialized microenvironments within the thymus are comprised of unique cell types with distinct roles in directing the development of a diverse, functional, and self-tolerant T cell repertoire. As they differentiate, thymocytes transit through a number of developmental intermediates that are associated with unique localization and migration patterns. For example, during one particular developmental transition, immature thymocytes more than double in speed as they become mature T cells that are among the fastest cells in the body. This transition is associated with dramatic changes in the expression of chemokine receptors and their antagonists, cell adhesion molecules, and cytoskeletal components to direct the maturing thymocyte population from the cortex to medulla. Here we discuss the dynamic changes in behavior that occur throughout thymocyte development, and provide an overview of the cell-intrinsic and extrinsic mechanisms that regulate human thymocyte migration.
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Affiliation(s)
- Joanna Halkias
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, 142 Life Sciences Addition, #3200, Berkeley, CA, 94720-3200, USA,
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136
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Li M, Li Q, Yang Z, Hu G, Li T, Chen X, Ao J. Identification of cathepsin B from large yellow croaker (Pseudosciaena crocea) and its role in the processing of MHC class II-associated invariant chain. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 45:313-320. [PMID: 24705226 DOI: 10.1016/j.dci.2014.03.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/27/2014] [Accepted: 03/27/2014] [Indexed: 06/03/2023]
Abstract
In teleost, cathepsin B has been identified from several species and shown to play roles in the host immune response during pathogen challenge. However, the mechanism of how cathepsin B modulates the immune response in teleosts remains poorly understood. In this study, we identified and characterized cathepsin B (LycCatB) and invariant chain (LycIi) from the large yellow croaker (Pseudosciaena crocea). Sequence comparison and phylogenetic analysis indicated that LycCatB and LycIi are highly conserved within teleosts. Quantitative RT-PCR analysis showed that LycCatB mRNA was widely expressed in all examined tissues. We then recombinantly expressed LycCatB and Lyc-TR-Ii (transmembrane domain removed Ii chain) in Pichia pastoris and Escherichiacoli, respectively. The recombinant LycCatB (rLycCatB) can hydrolyze the substrate Z-FR-AMC with a Km value of 40.68μM. Furthermore, co-incubation of rLycCatB with rLyc-TR-Ii led to an efficient cleavage of rLyc-TR-Ii in a time-dependant manner. These results indicated that cathepsin B may be involved in MHC class II-associated Ii processing in large yellow croaker, and provide new information helping to elucidate the immunological functions of teleost cathepsin B.
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Affiliation(s)
- Mingyu Li
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China
| | - Qiuhua Li
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China
| | - Zhijun Yang
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China
| | - Guohai Hu
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China
| | - Ting Li
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China.
| | - Jingqun Ao
- Key Laboratory of Marine Biogenetics and Resources, Third Institute of Oceanography, State Oceanic Administration, 184 Daxue Road, Xiamen 361005, China.
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137
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Bae SM, Lim W, Jeong W, Kim J, Bazer FW, Song G. Expression and regulation of avian cathepsin L in the oviduct during molting. Gen Comp Endocrinol 2014; 204:88-94. [PMID: 24859254 DOI: 10.1016/j.ygcen.2014.05.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 04/01/2014] [Accepted: 05/02/2014] [Indexed: 01/19/2023]
Abstract
Cathepsins (CTSs) are peptidases that have biological roles in degrading extracellular matrix, catabolism of intracellular proteins, and processing of pro-hormones. Of these, cathepsin L (CTSL) is closely associated with morphological changes in reproductive organs required for proper function in mammals, including humans and mice, but little is known about CTSL in avian species. In the present study, the expression of CTSL was investigated in the oviduct of hens during regression and recrudescence in response to molting. Our results revealed that expression of CTSL mRNA increased (P<0.001) when the oviduct underwent regression during the molting period in hens. In situ hybridization and immunohistochemial analyses detected CTSL mRNA and protein predominantly in the luminal (LE) and glandular epithelia (GE) during regression of the oviduct, but not during regeneration of the oviduct. Expression of CTSL decreased in the oviduct of chicks treated with diethylstilbestrol (DES, a synthetic estrogen agonist). Furthermore, we discovered four miRNAs including miR-23b, miR-551, miR-1464 and miR-1803 that regulate expression of the CTSL gene at the post-transcriptional level, which suggests that CTSL mRNA can be regulated by specific miRNAs via 3'-UTR in chickens. Results of the present research suggest that estrogen regulates expression of CTSL during regression of the oviduct during molting and that down-regulation of CTSL is likely a prerequisite for the normal regeneration of oviductal tissues following molting in laying hens.
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Affiliation(s)
- Seung-Min Bae
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea
| | - Whasun Lim
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea
| | - Wooyoung Jeong
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea
| | - Jinyoung Kim
- Department of Animal Resources Science, Dankook University, Cheonan 330-714, Republic of Korea
| | - Fuller W Bazer
- Center for Animal Biotechnology and Genomics, Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USA
| | - Gwonhwa Song
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea.
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138
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Kim HN, Chae YS, Shim WJ, Park CI, Jung JH. Combined effects of Iranian heavy crude oil and bacterial challenge (Streptococcus iniae) on biotransformation and innate immune responses in rockfish (Sebastes schlegeli). BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2014; 93:199-203. [PMID: 24898800 DOI: 10.1007/s00128-014-1307-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 05/26/2014] [Indexed: 06/03/2023]
Abstract
To clarify the effects of spilled crude oil on fish bacterial disease resistance, rockfish (Sebastes schlegeli) were exposed to Iranian Heavy crude oil (IHCO) and Streptomyces iniae in combination. Hepatic biotransformation enzymes (ethoxyresorufin O-de-ethylase, glutathione-S-transferase) and plasma biochemical parameters (glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and glucose) in fish exposed to IHCO were not significantly different from those in unexposed fish. The level of biliary 1-OH-pyrene and cytochrome P4501A mRNA expression increased in a dose-dependent manner with IHCO exposure. The interferon stimulated gene 15, interleukin-1beta and cathepsin L were increased significantly in the liver in IHCO-exposed fish, but not dose-dependently, but the granulocyte colony stimulating factor was not related to IHCO exposure. The percentage mortality in fish following a single exposure to S. iniae was positively correlated with IHCO exposure concentration. We concluded that IHCO exposure exacerbates fish mortality following environmental bacterial infection.
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Affiliation(s)
- Ha Na Kim
- Oil and POPs Research Group, Korea Institute of Ocean Science and Technology, 391 Jangbuk-ri, Jangmok-myon, Geoje, 656-834, Korea
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139
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Klein L, Kyewski B, Allen PM, Hogquist KA. Positive and negative selection of the T cell repertoire: what thymocytes see (and don't see). Nat Rev Immunol 2014; 14:377-91. [PMID: 24830344 DOI: 10.1038/nri3667] [Citation(s) in RCA: 854] [Impact Index Per Article: 85.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The fate of developing T cells is specified by the interaction of their antigen receptors with self-peptide-MHC complexes that are displayed by thymic antigen-presenting cells (APCs). Various subsets of thymic APCs are strategically positioned in particular thymic microenvironments and they coordinate the selection of a functional and self-tolerant T cell repertoire. In this Review, we discuss the different strategies that these APCs use to sample and process self antigens and to thereby generate partly unique, 'idiosyncratic' peptide-MHC ligandomes. We discuss how the particular composition of the peptide-MHC ligandomes that are presented by specific APC subsets not only shapes the T cell repertoire in the thymus but may also indelibly imprint the behaviour of mature T cells in the periphery.
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Affiliation(s)
- Ludger Klein
- Institute for Immunology, Ludwig Maximilians University, 80336 Munich, Germany
| | - Bruno Kyewski
- Division of Developmental Immunology, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Paul M Allen
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Kristin A Hogquist
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota 55414, USA
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140
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Allan ERO, Tailor P, Balce DR, Pirzadeh P, McKenna NT, Renaux B, Warren AL, Jirik FR, Yates RM. NADPH Oxidase Modifies Patterns of MHC Class II–Restricted Epitopic Repertoires through Redox Control of Antigen Processing. THE JOURNAL OF IMMUNOLOGY 2014; 192:4989-5001. [DOI: 10.4049/jimmunol.1302896] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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141
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Sant AJ, Chaves FA, Krafcik FR, Lazarski CA, Menges P, Richards K, Weaver JM. Immunodominance in CD4 T-cell responses: implications for immune responses to influenza virus and for vaccine design. Expert Rev Vaccines 2014; 6:357-68. [PMID: 17542751 DOI: 10.1586/14760584.6.3.357] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CD4 T cells play a primary role in regulating immune responses to pathogenic organisms and to vaccines. Antigen-specific CD4 T cells provide cognate help to B cells, a requisite event for immunoglobulin switch and affinity maturation of B cells that produce neutralizing antibodies and also provide help to cytotoxic CD8 T cells, critical for their expansion and persistence as memory cells. Finally, CD4 T cells may participate directly in pathogen clearance via cell-mediated cytotoxicity or through production of cytokines. Understanding the role of CD4 T-cell immunity to viruses and other pathogens, as well as evaluation of the efficacy of vaccines, requires insight into the specificity of CD4 T cells. This review focuses on the events within antigen-presenting cells that focus CD4 T cells toward a limited number of peptide antigens within the pathogen or vaccine. The molecular events are discussed in light of the special challenges that the influenza virus poses, owing to the high degree of genetic variability, unpredictable pathogenicity and the repeated encounters that human populations face with this highly infectious pathogenic organism.
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Affiliation(s)
- Andrea J Sant
- David H Smith Center for Vaccine Biology and Immunology, Aab Institute and Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA.
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142
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Endostatin and cathepsin-V in bronchoalveolar lavage fluid of patients with pulmonary sarcoidosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 833:55-61. [PMID: 25252891 DOI: 10.1007/5584_2014_26] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recently, it has been reported that lack of cathepsins prevent the development of lung granulomas in a mouse model of Besnier-Boeck-Schaumann (BBS) disease, sarcoidosis. There is no data about cathepsin V (Cath V) in bronchoalveolar lavage fluid (BALF) in humans. Endostatin is a novel inhibitor of lung epithelial cells. The role of this protein in BBS is not determined. The aim of this study was to evaluate the concentration of endostatin, Cath V, and IL-18 in BALF of BBS patients. We studied 22 BBS patients (Stage 2). The control group consisted of 20 healthy subjects. Cath V concentration was lower in BBS than in healthy group (16.03±8.60 vs. 32.25±21.90 pg/ml, p=0.004). Both endostatin and IL-18 levels were higher in BBS than in the control group (0.88±0.30 vs. 0.29±0.04 ng/ml, p=0.028; 40.37±31.60 vs. 14.61±1.30 pg/ml, p=0.007, respectively). In BBS there were correlations between the levels of endostatin and IL-18 (r=0.74, p=0.001) as well as endostatin and DLCO (diffusing capacity for carbon monoxide) (r=-0.6, p=0.013). Receiver-operating characteristic (ROC) curves were applied to find the cut-off for the BALF levels of Cath V, endostatin, and IL-18. We conclude that Cath V and endostatin may represent an index of pulmonary sarcoidosis activity.
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143
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Alves NL, Takahama Y, Ohigashi I, Ribeiro AR, Baik S, Anderson G, Jenkinson WE. Serial progression of cortical and medullary thymic epithelial microenvironments. Eur J Immunol 2014; 44:16-22. [PMID: 24214487 PMCID: PMC4253091 DOI: 10.1002/eji.201344110] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/11/2013] [Accepted: 11/05/2013] [Indexed: 01/07/2023]
Abstract
Thymic epithelial cells (TECs) provide key instructive signals for T-cell differentiation. Thymic cortical (cTECs) and medullary (mTECs) epithelial cells constitute two functionally distinct microenvironments for T-cell development, which derive from a common bipotent TEC progenitor. While seminal studies have partially elucidated events downstream of bipotent TECs in relation to the emergence of mTECs and their progenitors, the control and timing of the emergence of the cTEC lineage, particularly in relation to that of mTEC progenitors, has remained elusive. In this review, we describe distinct models that explain cTEC/mTEC lineage divergence from common bipotent progenitors. In particular, we summarize recent studies in mice providing evidence that mTECs, including the auto-immune regulator(+) subset, derive from progenitors initially endowed with phenotypic properties typically associated with the cTEC lineage. These observations support a novel "serial progression" model of TEC development, in which progenitors serially acquire cTEC lineage markers, prior to their commitment to the mTEC differentiation pathway. Gaining a better understanding of the phenotypic properties of early stages in TEC progenitor development should help in determining the mechanisms regulating cTEC/mTEC lineage development, and in strategies aimed at thymus reconstitution involving TEC therapy.
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Affiliation(s)
- Nuno L Alves
- Infection and Immunity Unit, Institute for Molecular and Cellular Biology, University of PortoPorto, Portugal
| | - Yousuke Takahama
- Division of Experimental Immunology, Institute for Genome Research, University of TokushimaTokushima, Japan
| | - Izumi Ohigashi
- Division of Experimental Immunology, Institute for Genome Research, University of TokushimaTokushima, Japan
| | - Ana R Ribeiro
- Infection and Immunity Unit, Institute for Molecular and Cellular Biology, University of PortoPorto, Portugal
| | - Song Baik
- Medical Research Council Centre for Immune Regulation, Institute for Biomedical Research, Medical School, University of BirminghamBirmingham, UK
| | - Graham Anderson
- Medical Research Council Centre for Immune Regulation, Institute for Biomedical Research, Medical School, University of BirminghamBirmingham, UK
| | - William E Jenkinson
- Medical Research Council Centre for Immune Regulation, Institute for Biomedical Research, Medical School, University of BirminghamBirmingham, UK
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144
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Intracellular Toll-Like Receptor Recruitment and Cleavage in Endosomal/Lysosomal Organelles. Methods Enzymol 2014; 535:141-7. [DOI: 10.1016/b978-0-12-397925-4.00009-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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145
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Exploring the MHC-peptide matrix of central tolerance in the human thymus. Nat Commun 2013; 4:2039. [PMID: 23783831 DOI: 10.1038/ncomms3039] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 05/21/2013] [Indexed: 01/22/2023] Open
Abstract
Ever since it was discovered that central tolerance to self is imposed on developing T cells in the thymus through their interaction with self-peptide major histocompatibility complexes on thymic antigen-presenting cells, immunologists have speculated about the nature of these peptides, particularly in humans. Here, to shed light on the so-far unknown human thymic peptide repertoire, we analyse peptides eluted from isolated thymic dendritic cells, dendritic cell-depleted antigen-presenting cells and whole thymus. Bioinformatic analysis of the 842 identified natural major histocompatibility complex I and II ligands reveals significant cross-talk between major histocompatibility complex-class I and II pathways and differences in source protein representation between individuals as well as different antigen-presenting cells. Furthermore, several autoimmune- and tumour-related peptides, from enolase and vimentin for example, are presented in the healthy thymus. 302 peptides are directly derived from negatively selecting dendritic cells, thus providing the first global view of the peptide matrix in the human thymus that imposes self-tolerance in vivo.
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146
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Fortin JS, Cloutier M, Thibodeau J. Exposing the Specific Roles of the Invariant Chain Isoforms in Shaping the MHC Class II Peptidome. Front Immunol 2013; 4:443. [PMID: 24379812 PMCID: PMC3861868 DOI: 10.3389/fimmu.2013.00443] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 11/26/2013] [Indexed: 11/26/2022] Open
Abstract
The peptide repertoire (peptidome) associated with MHC class II molecules (MHCIIs) is influenced by the polymorphic nature of the peptide binding groove but also by cell-intrinsic factors. The invariant chain (Ii) chaperones MHCIIs, affecting their folding and trafficking. Recent discoveries relating to Ii functions have provided insights as to how it edits the MHCII peptidome. In humans, the Ii gene encodes four different isoforms for which structure-function analyses have highlighted common properties but also some non-redundant roles. Another layer of complexity arises from the fact that Ii heterotrimerizes, a characteristic that has the potential to affect the maturation of associated MHCIIs in many different ways, depending on the isoform combinations. Here, we emphasize the peptide editing properties of Ii and discuss the impact of the various isoforms on the MHCII peptidome.
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Affiliation(s)
- Jean-Simon Fortin
- Laboratoire d'Immunologie Moléculaire, Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal , Montréal, QC , Canada
| | - Maryse Cloutier
- Laboratoire d'Immunologie Moléculaire, Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal , Montréal, QC , Canada
| | - Jacques Thibodeau
- Laboratoire d'Immunologie Moléculaire, Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal , Montréal, QC , Canada
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147
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ten Broeke T, Wubbolts R, Stoorvogel W. MHC class II antigen presentation by dendritic cells regulated through endosomal sorting. Cold Spring Harb Perspect Biol 2013; 5:a016873. [PMID: 24296169 DOI: 10.1101/cshperspect.a016873] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
For the initiation of adaptive immune responses, dendritic cells present antigenic peptides in association with major histocompatibility complex class II (MHCII) to naïve CD4(+) T lymphocytes. In this review, we discuss how antigen presentation is regulated through intracellular processing and trafficking of MHCII. Newly synthesized MHCII is chaperoned by the invariant chain to endosomes, where peptides from endocytosed pathogens can bind. In nonactivated dendritic cells, peptide-loaded MHCII is ubiquitinated and consequently sorted by the ESCRT machinery to intraluminal vesicles of multivesicular bodies, ultimately leading to lysosomal degradation. Ubiquitination of newly synthesized MHCII is blocked when dendritic cells are activated, now allowing its transfer to the cell surface. This mode of regulation for MHCII is a prime example of how molecular processing and sorting at multivesicular bodies can determine the expression of signaling receptors at the plasma membrane.
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Affiliation(s)
- Toine ten Broeke
- Utrecht University, Faculty of Veterinary Medicine, Department of Biochemistry and Cell Biology, Yalelaan 2, 3584 CM, Utrecht, The Netherlands
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148
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Xu X, Greenland J, Baluk P, Adams A, Bose O, McDonald DM, Caughey GH. Cathepsin L protects mice from mycoplasmal infection and is essential for airway lymphangiogenesis. Am J Respir Cell Mol Biol 2013; 49:437-44. [PMID: 23600672 DOI: 10.1165/rcmb.2013-0016oc] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Cathepsin L (Ctsl) is a proposed therapeutic target to control inflammatory responses in a number of disease states. However, Ctsl is thought to support host defense via its involvement in antigen presentation pathways. Hypothesizing that Ctsl helps combat bacterial infection, we investigated its role in Mycoplasma pulmonis-infected mice as a model of acute and chronic infectious airway inflammation. Responses to the airway inoculation of mycoplasma were compared in Ctsl(-/-) and Ctsl(+/+) mice. After infection, Ctsl(-/-) mice demonstrated more body weight loss, greater mortality (22% versus 0%, respectively), and heavier lungs than Ctsl(+/+) mice, but had smaller bronchial lymph nodes. The burden of live mycoplasma in lungs was 247-fold greater in Ctsl(-/-) mice than in Ctsl(+/+) mice after infection for 3 days. Ctsl(-/-) mice exhibited more severe pneumonia and neutrophil-rich, airway-occlusive exudates, which developed more rapidly than in Ctsl(+/+) mice. Compared with the conspicuous remodeling of lymphatics after infection in Ctsl(+/+) mice, little lymphangiogenesis occurred in Ctsl(-/-) mice, but blood vessel remodeling and tissue inflammation were similarly severe. Titers of mycoplasma-reactive IgM, IgA, and IgG in blood in response to live and heat-killed organisms were similar to those in Ctsl(+/+) mice. However, enzyme-linked immunosorbent spot assays revealed profound reductions in the cellular IFN-γ response to mycoplasma antigen. These findings suggest that Ctsl helps contain mycoplasma infection by supporting lymphangiogenesis and cellular immune responses to infection, and our findings predict that the therapeutic inhibition of Ctsl could increase the severity of mycoplasmal infections.
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Affiliation(s)
- Xiang Xu
- Department of Medicine, University of California at San Francisco, CA 94121, USA
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149
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Melichar HJ, Ross JO, Herzmark P, Hogquist KA, Robey EA. Distinct temporal patterns of T cell receptor signaling during positive versus negative selection in situ. Sci Signal 2013; 6:ra92. [PMID: 24129702 DOI: 10.1126/scisignal.2004400] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The recognition by the T cell receptor (TCR) of self-peptides presented by the major histocompatibility complex (MHC) on antigen-presenting cells, such as dendritic cells and thymic epithelial cells, controls T cell fate in the thymus, with weak TCR signals inducing survival (positive selection) and stronger signals inducing death (negative selection). In vitro studies indicate that peptide ligands that induce positive selection stimulate a low, but sustained, pattern of TCR signaling; however, the temporal pattern of TCR signaling in MHC class I-restricted thymocytes (thymocytes that are presented with peptides by MHC class I) in the thymus, under conditions that support positive selection, is unknown. We addressed this question by examining intracellular Ca(2+) dynamics and migratory changes in thymocytes undergoing positive and negative selection in thymic slices. Brief, serial signaling events that were separated by migratory periods and low cytosolic Ca(2+) concentrations correlated with the positive selection of MHC class I-restricted thymocytes, whereas sustained Ca(2+) signaling and the arrest of thymocytes were associated with negative selection. Low-avidity peptides and the presentation of peptides by cortical thymic epithelial cells, rather than dendritic cells, failed to induce strong migratory arrest of thymocytes, which led to transient TCR signaling. Thus, we provide a comparison of positive and negative selection signals in situ and suggest that the absence of strong stop signals distinguishes between positive and negative selection.
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Affiliation(s)
- Heather J Melichar
- 1Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
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150
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Du X, Chen NLH, Wong A, Craik CS, Brömme D. Elastin degradation by cathepsin V requires two exosites. J Biol Chem 2013; 288:34871-81. [PMID: 24121514 DOI: 10.1074/jbc.m113.510008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cathepsin V is a highly effective elastase and has been implicated in physiological and pathological extracellular matrix degradation. However, its mechanism of action remains elusive. Whereas human cathepsin V exhibits a potent elastolytic activity, the structurally homologous cathepsin L, which shares a 78% amino acid sequence, has only a minimal proteolytic activity toward insoluble elastin. This suggests that there are distinct structural domains that play an important role in elastinolysis. In this study, a total of 11 chimeras of cathepsins V and L were generated to identify elastin-binding domains in cathepsin V. Evaluation of these chimeras revealed two exosites contributing to the elastolytic activity of cathepsin V that are distant from the active cleft of the protease and are located in surface loop regions. Replacement of exosite 1 or 2 with analogous residues from cathepsin L led to a 75 and 43% loss in the elastolytic activity, respectively. Replacement of both exosites yielded a non-elastase variant similar to that of cathepsin L. Identification of these exosites may contribute to the design of inhibitors that will only affect the elastolytic activity of cysteine cathepsins without interfering with other physiological protease functions.
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Affiliation(s)
- Xin Du
- From the Department of Biochemistry and Molecular Biology, Faculty of Medicine, Center for Blood Research, and
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