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Liu H, Dang R, Zhang W, Hong J, Li X. SNARE proteins: Core engines of membrane fusion in cancer. Biochim Biophys Acta Rev Cancer 2024:189148. [PMID: 38960006 DOI: 10.1016/j.bbcan.2024.189148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 06/23/2024] [Accepted: 06/27/2024] [Indexed: 07/05/2024]
Abstract
Vesicles are loaded with a variety of cargoes, including membrane proteins, secreted proteins, signaling molecules, and various enzymes, etc. Not surprisingly, vesicle transport is essential for proper cellular life activities including growth, division, movement and cellular communication. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) mediate membrane fusion of vesicles with their target compartments that is fundamental for cargo delivery. Recent studies have shown that multiple SNARE family members are aberrantly expressed in human cancers and actively contribute to malignant proliferation, invasion, metastasis, immune evasion and treatment resistance. Here, the localization and function of SNARE proteins in eukaryotic cells are firstly mapped. Then we summarize the expression and regulation of SNAREs in cancer, and describe their contribution to cancer progression and mechanisms, and finally we propose engineering botulinum toxin as a strategy to target SNAREs for cancer treatment.
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Affiliation(s)
- Hongyi Liu
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, China; Hunan International Scientific and Technological Cooperation Base of Brain Tumor Research, Xiangya Hospital, Central South University, Changsha, China
| | - Ruiyue Dang
- Department of Oncology, Xiangya Hospital, Central South University, Changsha, China
| | - Wei Zhang
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, China; Hunan International Scientific and Technological Cooperation Base of Brain Tumor Research, Xiangya Hospital, Central South University, Changsha, China
| | - Jidong Hong
- Department of Oncology, Xiangya Hospital, Central South University, Changsha, China.
| | - Xuejun Li
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, China; Hunan International Scientific and Technological Cooperation Base of Brain Tumor Research, Xiangya Hospital, Central South University, Changsha, China.
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2
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Shinozuka T, Kanda M, Sato Y, Shimizu D, Tanaka C, Umeda S, Inokawa Y, Hattori N, Hayashi M, Nakayama G, Kodera Y. Increased STX3 transcript and protein levels were associated with poor prognosis in two independent cohorts of esophageal squamous cell carcinoma patients. Cancer Med 2023; 12:22185-22195. [PMID: 38014487 PMCID: PMC10757105 DOI: 10.1002/cam4.6770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/07/2023] [Accepted: 11/17/2023] [Indexed: 11/29/2023] Open
Abstract
BACKGROUND Some conventional prognostic biomarkers for esophageal squamous cell carcinoma (ESCC) have the disadvantage that they have only been investigated at the level of either mRNA or protein levels or only in individual cohorts. Associations between Syntaxin 3 (STX3) expression and malignancy have been reported in several tumor types but not in ESCC. Here, we investigated the levels of both STX3 mRNA and protein, and its prognostic potential in two independent cohorts of patients with ESCC. METHODS STX3 mRNA levels were examined in surgical specimens by quantitative PCR in a cohort that included 176 ESCC patients. STX3 protein levels were investigated in surgically resected ESCC tissues by immunohistochemistry using tissue microarrays in a different cohort of 177 ESCC patients. Correlations were analyzed between the expression of STX3 mRNA and protein with clinicopathological factors and long-term prognosis. RESULTS Quantitative PCR indicated a significant association between high level of STX3 mRNA expression and lymph node involvement, pathological stage, and poor overall survival. The multivariate analysis demonstrated that high STX3 mRNA expression was independently associated with poor overall survival outcomes. Immunohistochemistry revealed that STX3 protein expression in ESCC tissues and high STX3 protein expression were also significantly correlated with unfavorable overall survival. CONCLUSIONS Overexpression of STX3 mRNA and protein may serve as potential prognostic biomarkers for ESCC patients.
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Affiliation(s)
- Takahiro Shinozuka
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Mitsuro Kanda
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yusuke Sato
- Department of Thoracic SurgeryAkita University Graduate School of MedicineAkitaJapan
| | - Dai Shimizu
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Chie Tanaka
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Shinichi Umeda
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yoshikuni Inokawa
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Norifumi Hattori
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Masamichi Hayashi
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Goro Nakayama
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yasuhiro Kodera
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
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3
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Yanamandra AK, Bhusari S, Del Campo A, Sankaran S, Qu B. In vitro evaluation of immune responses to bacterial hydrogels for the development of living therapeutic materials. BIOMATERIALS ADVANCES 2023; 153:213554. [PMID: 37480604 DOI: 10.1016/j.bioadv.2023.213554] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/03/2023] [Accepted: 07/06/2023] [Indexed: 07/24/2023]
Abstract
In living therapeutic materials (LTMs), organisms genetically programmed to produce and deliver drugs are encapsulated in porous matrices acting as physical barriers between the therapeutic organisms and the host cells. LTMs consisting of engineered E. coli encapsulated in Pluronic F127-based hydrogels have been frequently used in LTM designs but their immunogenicity has not been tested. In this study, we investigate the response of human peripheral blood mononuclear cells (PBMCs) exposed to this bacteria/hydrogel combination. The release of inflammation-related cytokines and cytotoxic proteins and the subsets of natural killer cells and T cells were examined. Encapsulation of the bacteria in hydrogels considerably lowers their immunogenicity. ClearColi, an endotoxin-free variant of E. coli, did not polarize NK cells into the more cytolytic CD16dim subset as E. coli. Our results demonstrate that ClearColi-encapsulated hydrogels generate low immunogenic response and are suitable candidates for the development of LTMs for in vivo testing to assess a potential clinical use. Nevertheless, we observed a stronger immune response (elevated levels of IFNγ, IL-6 and cytotoxic proteins) in pro-inflammatory PBMCs characterized by a high spontaneous release of IL-2. This highlights the need to identify recipients who have a higher likelihood of experiencing undesired immune responses to LTMs with IL-2 serving as a potential predictive marker. Additionally, including anti-inflammatory measures in living therapeutic material designs could be beneficial for such recipients.
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Affiliation(s)
- Archana K Yanamandra
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany; INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Shardul Bhusari
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | | | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany; INM - Leibniz Institute for New Materials, Saarbrücken, Germany.
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4
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Cappelletti P, Filareti M, Masuelli L, Bei R, Hassanzadeh K, Corbo M, Feligioni M. Syntaxin-1a and SNAP-25 expression level is increased in the blood samples of ischemic stroke patients. Sci Rep 2022; 12:14483. [PMID: 36008522 PMCID: PMC9411545 DOI: 10.1038/s41598-022-18719-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/18/2022] [Indexed: 11/09/2022] Open
Abstract
The interest for the discovery of blood biomarkers for several neurological disorders, including Ischemic Stroke (IS), is growing and their identification in blood samples would be revolutionary allowing a fast and better pathology prediction or outcome and to collect information on patient recovery. The increased permeability of the blood-brain barrier, following a brain infarct, allows the detection of brain proteins in the blood flow. In this work, we analyzed the expression levels of two synaptic proteins Syntaxin (STX)-1a and Synaptosomal Associated Protein, 25 kDa (SNAP-25), in Peripheral Blood Mononuclear Cell (PBMC), serum and in Neuronal Derived Extracellular vesicles (NDEs) of IS patients, age and sex matched healthy control (HC) and younger HC (Y-HC). Interestingly, we identified STX-1a protein in the cytoplasm of PBMC and both STX-1a and SNAP-25 expression levels were significantly augmented in all IS patient's blood fractions compared to control subjects. In addition, STX-1a blood levels correlated with the IS clinical scales National Institutes of Health Stroke Scale (NIH-SS) and the modified Barthel Index (BI). These results prompted us to speculate that STX-1a and SNAP-25 hematic fluctuations depict the brain damage after an ischemic attack and that their hematic detection could represent a novel and accessible IS biomarkers.
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Affiliation(s)
- Pamela Cappelletti
- Department of Neuro-Rehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | - Melania Filareti
- Department of Neuro-Rehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | - Laura Masuelli
- Department of Experimental Medicine, University of Rome "Sapienza", Rome, Italy
| | - Roberto Bei
- Department of Clinical Sciences and Translational Medicine, University of Rome "Tor Vergata", Rome, Italy
| | - Kambiz Hassanzadeh
- European Brain Research Institute (EBRI) Rita Levi Montalcini Foundation, Viale Regina Elena 295, 00161, Rome, Italy.,Fondazione Pisana per la Scienza (FPS), Pisa, Italy
| | - Massimo Corbo
- Department of Neuro-Rehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | - Marco Feligioni
- Department of Neuro-Rehabilitation Sciences, Casa Cura Policlinico, Milan, Italy. .,European Brain Research Institute (EBRI) Rita Levi Montalcini Foundation, Viale Regina Elena 295, 00161, Rome, Italy.
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De Souza MM, Koltes DA, Beiki H, Sales MA, Tsai T, Maxwell CV, Zhao J, Koltes JE. Early-Life Exposure of Pigs to Topsoil Alters miRNA and mRNA Expression in Peripheral Blood Mononuclear Cells. Front Genet 2022; 13:886875. [PMID: 36081988 PMCID: PMC9445269 DOI: 10.3389/fgene.2022.886875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022] Open
Abstract
Exposure to less-hygienic conditions during early childhood has been associated with stimulation and development of the immune system. A recent study indicated that exposure of piglets to soil-borne microbes during lactation was related with modulation of gut microbiota and immune function. To identify the potential molecular mechanisms and pathways impacted by early-life topsoil exposure, we analyzed the messenger RNA (mRNA) and micro-RNA (miRNA) expression in peripheral blood mononuclear cells (PBMCs) from these piglets. Total RNA was extracted from the PBMCs of piglets exposed to topsoil only from d 4–d 21 of life (mRNA n = 6; miRNA n = 5) or unexposed control pigs (mRNA n = 6; miRNA n = 8) at 11, 20, and 56 days of age. Small RNA and mRNA were sequenced with 50-bp single-end reads using Illumina chemistry. Sequence data were quality checked with FASTQC software and aligned to the Sscrofa 11.1 genome with the STAR aligner for mRNA and mirDeep2 for miRNA. Differential expression (DE) analysis was performed using PROC Glimmix of SAS to evaluate changes in expression due to topsoil exposure over time with genes declared DE at a false discovery rate (FDR) of q < 0.10. A total of 138 mRNA and 21 miRNAs were identified as DE for the treatment by age interaction. Ontology enrichment analysis of DE mRNA revealed Gene ontology (GO) terms directly involved in the connection between T-cell and antigen-presenting cells that are associated with T-cell activation. Key regulatory genes identified include PTPRJ, ITGB3, TRBV30, CD3D, mir-143, mir-29, and mir-148a. While these results require validation, this study provides data supporting the hypothesis that less-hygienic environments during early life may contribute to the development of the immune system.
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Affiliation(s)
- M. M. De Souza
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - D. A. Koltes
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - H. Beiki
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - M. A. Sales
- Department of Animal Science, University of Arkansas-Division of Agriculture, Fayetteville, AR, United States
| | - T. Tsai
- Department of Animal Science, University of Arkansas-Division of Agriculture, Fayetteville, AR, United States
| | - C. V. Maxwell
- Department of Animal Science, University of Arkansas-Division of Agriculture, Fayetteville, AR, United States
| | - J. Zhao
- Department of Animal Science, University of Arkansas-Division of Agriculture, Fayetteville, AR, United States
| | - J. E. Koltes
- Department of Animal Science, Iowa State University, Ames, IA, United States
- *Correspondence: J. E. Koltes,
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Kline EM, Houser MC, Herrick MK, Seibler P, Klein C, West A, Tansey MG. Genetic and Environmental Factors in Parkinson's Disease Converge on Immune Function and Inflammation. Mov Disord 2021; 36:25-36. [PMID: 33314312 PMCID: PMC8285924 DOI: 10.1002/mds.28411] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/20/2020] [Accepted: 11/12/2020] [Indexed: 12/14/2022] Open
Abstract
Idiopathic Parkinson's disease (iPD) is a movement disorder characterized by the degeneration of dopaminergic neurons and aggregation of the protein α-synuclein. Patients with iPD vary in age of symptom onset, rate of progression, severity of motor and non-motor symptoms, and extent of central and peripheral inflammation. Genetic and environmental factors are believed to act synergistically in iPD pathogenesis. We propose that environmental factors (pesticides and infections) increase the risk for iPD via the immune system and that the role of PD risk genes in immune cells is worthy of investigation. This review highlights the major PD-relevant genes expressed in immune cells and key environmental factors that activate immune cells and, alone or in combination with other factors, may contribute to iPD pathogenesis. By reviewing these interactions, we seek to enable the future development of immunomodulatory approaches to prevent or delay onset of iPD. © 2020 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Elizabeth M Kline
- Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Madelyn C Houser
- Laney Graduate School, Emory University, Atlanta, Georgia, USA
- School of Nursing, Emory University, Atlanta, Georgia, USA
| | - Mary K Herrick
- Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Departments of Neuroscience and Neurology, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Philip Seibler
- Institute of Neurogenetics, University of Luebeck, Luebeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Luebeck, Luebeck, Germany
| | - Andrew West
- Duke Center for Neurodegeneration and Neurotherapeutics, Duke University, Durham, North Carolina, USA
| | - Malú G Tansey
- Departments of Neuroscience and Neurology, Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, Florida, USA
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Birkner K, Wasser B, Ruck T, Thalman C, Luchtman D, Pape K, Schmaul S, Bitar L, Krämer-Albers EM, Stroh A, Meuth SG, Zipp F, Bittner S. β1-Integrin- and KV1.3 channel-dependent signaling stimulates glutamate release from Th17 cells. J Clin Invest 2020; 130:715-732. [PMID: 31661467 DOI: 10.1172/jci126381] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 10/22/2019] [Indexed: 12/22/2022] Open
Abstract
Although the impact of Th17 cells on autoimmunity is undisputable, their pathogenic effector mechanism is still enigmatic. We discovered soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) complex proteins in Th17 cells that enable a vesicular glutamate release pathway that induces local intracytoplasmic calcium release and subsequent damage in neurons. This pathway is glutamine dependent and triggered by binding of β1-integrin to vascular cell adhesion molecule 1 (VCAM-1) on neurons in the inflammatory context. Glutamate secretion could be blocked by inhibiting either glutaminase or KV1.3 channels, which are known to be linked to integrin expression and highly expressed on stimulated T cells. Although KV1.3 is not expressed in CNS tissue, intrathecal administration of a KV1.3 channel blocker or a glutaminase inhibitor ameliorated disability in experimental neuroinflammation. In humans, T cells from patients with multiple sclerosis secreted higher levels of glutamate, and cerebrospinal fluid glutamine levels were increased. Altogether, our findings demonstrate that β1-integrin- and KV1.3 channel-dependent signaling stimulates glutamate release from Th17 cells upon direct cell-cell contact between Th17 cells and neurons.
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Affiliation(s)
- Katharina Birkner
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Beatrice Wasser
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Tobias Ruck
- Department of Neurology, University of Muenster, Muenster, Germany
| | - Carine Thalman
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Dirk Luchtman
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Katrin Pape
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Samantha Schmaul
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Lynn Bitar
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Albrecht Stroh
- Institute for Pathophysiology, FTN, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sven G Meuth
- Department of Neurology, University of Muenster, Muenster, Germany
| | - Frauke Zipp
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Stefan Bittner
- Department of Neurology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn2, ), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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8
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Sun W, Tian BX, Wang SH, Liu PJ, Wang YC. The function of SEC22B and its role in human diseases. Cytoskeleton (Hoboken) 2020; 77:303-312. [PMID: 32748571 DOI: 10.1002/cm.21628] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/14/2020] [Accepted: 07/29/2020] [Indexed: 01/04/2023]
Abstract
Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins are a large protein complex that is involved in the membrane fusion in vesicle trafficking, cell growth, cytokinesis, membrane repair, and synaptic transmission. As one of the SNARE proteins, SEC22B functions in membrane fusion of vesicle trafficking between the endoplasmic reticulum and the Golgi apparatus, antigen cross-presentation, secretory autophagy, and other biological processes. However, apart from not being SNARE proteins, there is little knowledge known about its two homologs (SEC22A and SEC22C). SEC22B alterations have been reported in many human diseases, especially, many mutations of SEC22B in human cancers have been detected. In this review, we will introduce the specific functions of SEC22B, and summarize the researches about SEC22B in human cancers and other diseases. These findings have laid the foundation for further studies to clarify the exact mechanism of SEC22B in the pathological process and to seek new therapeutic targets and better treatment strategies.
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Affiliation(s)
- Wei Sun
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory for Tumor Precision Medicine of Shaanxi Province, Xi'an Jiaotong University, Xi'an, China
| | - Bi-Xia Tian
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory for Tumor Precision Medicine of Shaanxi Province, Xi'an Jiaotong University, Xi'an, China
| | - Shu-Hong Wang
- Department of Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Pei-Jun Liu
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory for Tumor Precision Medicine of Shaanxi Province, Xi'an Jiaotong University, Xi'an, China
| | - Yao-Chun Wang
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory for Tumor Precision Medicine of Shaanxi Province, Xi'an Jiaotong University, Xi'an, China
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9
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Tsuru E, Oryu K, Sawada K, Nishihara M, Tsuda M. Complexin 2 regulates secretion of immunoglobulin in antibody-secreting cells. Immun Inflamm Dis 2019; 7:318-325. [PMID: 31691534 PMCID: PMC6842823 DOI: 10.1002/iid3.276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/27/2019] [Accepted: 10/17/2019] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION Complexins (CPLXs), initially identified in neuronal presynaptic terminals, are cytoplasmic proteins that interact with the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) complex to regulate the fusion of vesicles to the plasma membrane. Although much is known about CPLX function in neuronal synaptic vesicle exocytosis, their distribution and role in immune cells are still unclear. In this study, we investigated CPLX2 knockout (KO) mice to reveal the role of CPLXs in exocytosis of lymphocytes. METHODS We examined the expression of CPLXs and SNAREs in lymphocytes. To study the effect of CPLXs on the immune system in vivo, we analyzed the immune phenotype of CPLX2 KO mice. Furthermore, antibodies secretion from the peritoneal cavity, spleen, and bone marrow cells of wild-type (WT) and CPLX2 KO mice were determined. RESULTS CPLX2 was detected in B cells but not in T cells, while other CPLXs and SNAREs were expressed at a similar level in both B and T cells. To clarify the function of CPLX2 in B lymphocytes, serum concentrations of immunoglobulin G (IgG), IgA, IgM, and IgE were measured in WT and CPLX2 KO mice using enzyme-linked immunosorbent assay. The level of IgM, which mainly consists of natural antibodies, was higher in KO mice than that in WT mice, while the levels of other antibodies were similar in both types of mice. Additionally, we found that spontaneous secretion of IgM and IgG1 was enhanced from the splenic antibody-secreting cells (ASCs) of CPLX2 KO mice. CONCLUSION Our data suggest that CPLX2 inhibits spontaneous secretion of IgM and IgG1 from splenic ASCs. This study provides new insight into the mechanism of antibody secretion of ASCs.
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Affiliation(s)
- Emi Tsuru
- Institute for Laboratory Animal Research, Science Research CenterKochi UniversityKochiJapan
| | - Kohei Oryu
- Institute for Laboratory Animal Research, Science Research CenterKochi UniversityKochiJapan
| | - Ken Sawada
- Kokorono Support CenterKochi Health Sciences CenterKochiJapan
| | - Makoto Nishihara
- Center for Interdisciplinary PainAichi Medical UniversityAichiJapan
| | - Masayuki Tsuda
- Institute for Laboratory Animal Research, Science Research CenterKochi UniversityKochiJapan
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Chitirala P, Ravichandran K, Galgano D, Sleiman M, Krause E, Bryceson YT, Rettig J. Cytotoxic Granule Exocytosis From Human Cytotoxic T Lymphocytes Is Mediated by VAMP7. Front Immunol 2019; 10:1855. [PMID: 31447853 PMCID: PMC6692471 DOI: 10.3389/fimmu.2019.01855] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Accepted: 07/23/2019] [Indexed: 11/13/2022] Open
Abstract
Cytotoxic T lymphocytes kill infected or malignant cells through the directed release of cytotoxic substances at the site of target cell contact, the immunological synapse. While genetic association studies of genes predisposing to early-onset life-threatening hemophagocytic lymphohistiocytosis has identified components of the plasma membrane fusion machinery, the identity of the vesicular components remain enigmatic. Here, we identify VAMP7 as an essential component of the vesicular fusion machinery of primary, human T cells. VAMP7 co-localizes with granule markers throughout all stages of T cell maturation and simultaneously fuses with granule markers at the IS. Knock-down of VAMP7 expression significantly decreased the killing efficiency of T cells, without diminishing early T cell receptor signaling. VAMP7 exerts its function in a SNARE complex with Syntaxin11 and SNAP-23 on the plasma membrane. The identification of the minimal fusion machinery in T cells provides a starting point for the development of potential drugs in immunotherapy.
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Affiliation(s)
- Praneeth Chitirala
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Keerthana Ravichandran
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Donatella Galgano
- Center for Hematology and Regenerative Medicine (HERM), Karolinska Institute, Stockholm, Sweden
| | - Marwa Sleiman
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Elmar Krause
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Yenan T. Bryceson
- Center for Hematology and Regenerative Medicine (HERM), Karolinska Institute, Stockholm, Sweden
| | - Jens Rettig
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
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11
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Ultrastructural changes in peripheral blood leukocytes in α-synuclein knockout mice. Blood Cells Mol Dis 2018; 73:33-37. [PMID: 30195626 DOI: 10.1016/j.bcmd.2018.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/31/2018] [Accepted: 09/01/2018] [Indexed: 01/01/2023]
Abstract
Effects of α-synuclein deficiency on cellular blood components have not been extensively investigated. This study evaluated ultrastructural changes of leukocytes in α-synuclein knockout (KO) mice using electron microscopy (EM). The following ultrastructural characteristics were quantified in leukocytes: mitochondria, primary granules, specific granules (SG), Golgi apparatus (GA), inclusions, rough-endoplasmic reticulum (RER), smooth-endoplasmic reticulum (SER), and cellular projections (CP). EM showed increased numbers or amounts of SG, inclusions, and SER in KO group (5.3 ± 4.5 in WT vs. 14.1 ± 10.3 in KO, p = 0.02; 0.4 ± 0.9 in WT vs. 3.2 ± 2.8 in KO, p = 0.007; and 7.7 ± 6.7 in WT vs. 17.7 ± 12.2 in KO, p = 0.03, respectively). Although CP number was not significantly different between the two groups (13.4 ± 5.3 in WT vs. 16.3 ± 7.5 in KO, p = 0.32), their size and shapes were altered in KO mice. Notably, findings occurred in the setting of significant lymphopenia. α-Synuclein deficiency leads to changes in size and shape of secretory particles and increases in SER, SG, and inclusions, indicating a potential role for α-synuclein in vesicular trafficking in leukocytes. Further studies are needed to elucidate functions mediated by α-synuclein.
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12
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Lesteberg K, Orange J, Makedonas G. Recycling endosomes in human cytotoxic T lymphocytes constitute an auxiliary intracellular trafficking pathway for newly synthesized perforin. Immunol Res 2017; 65:1031-1045. [PMID: 28822075 PMCID: PMC5834944 DOI: 10.1007/s12026-017-8945-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Although cytotoxic T lymphocytes (CTLs) store perforin within cytoplasmic secretory granules for immediate use, perforin is synthesized anew within hours of TCR stimulation. Previously, we observed new perforin protein at an immunologic synapse independent of secretory lysosomes; herein, we aimed to determine how new perforin transits to the synapse if not via lytic granules. We analyzed antigen-specific human CTLs via imaging flow cytometry and high-resolution confocal microscopy, with attention to intracellular trafficking components and new perforin. The recycling endosome compartments identified by rab8, rab11a, rab4, and rab37 co-localized with new perforin, as well as the SNAREs vti1b and VAMP4. After ablating the function of the recycling endosome pathway, we observed a relative accumulation of new perforin in rab8 vesicles. The recycling endosome pathway may serve as an auxiliary intracellular route for the delivery of new perforin to an immunologic synapse in order to perpetuate a cytotoxic response.
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Affiliation(s)
- Kelsey Lesteberg
- Center for Human Immunobiology, Texas Children's Hospital & Baylor College of Medicine, Houston, TX, USA
- Graduate Program in Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Jordan Orange
- Center for Human Immunobiology, Texas Children's Hospital & Baylor College of Medicine, Houston, TX, USA
- Graduate Program in Immunology, Baylor College of Medicine, Houston, TX, USA
| | - George Makedonas
- Center for Human Immunobiology, Texas Children's Hospital & Baylor College of Medicine, Houston, TX, USA.
- Graduate Program in Immunology, Baylor College of Medicine, Houston, TX, USA.
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13
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Abstract
Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells target infected or transformed cells with perforin-containing cytotoxic granules through immune synapses, while platelets secrete several types of granules which contents are essential for thrombosis and hemostasis. Recent work has culminated in the notion that an exocytic SNARE complex, based on a very similar set of components, is primarily responsible for exocytosis of the diverse granules in these different cell types. Granule exocytosis is, in particular, uniquely dependent on the atypical Q-SNARE syntaxin 11, its interacting partners of the Sec/Munc (SM) family, and is regulated by Rab27a. Mutations in these exocytic components underlie disease manifestations of familial hemophagocytic lymphohistiocytosis (FHL) subtypes, characterized by hyperactivation of the immune system, as well as platelet granule secretion defects. Here we discuss the key discoveries that led to the converging notion of the syntaxin 11-based exocytosis machinery for cytotoxic granules and platelet-derived granules.
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Affiliation(s)
- Bor Luen Tang
- a Department of Biochemistry , Yong Loo Lin School of Medicine, National University of Singapore , Singapore and.,b NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore , Singapore
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14
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Lou J, Rossy J, Deng Q, Pageon SV, Gaus K. New Insights into How Trafficking Regulates T Cell Receptor Signaling. Front Cell Dev Biol 2016; 4:77. [PMID: 27508206 PMCID: PMC4960267 DOI: 10.3389/fcell.2016.00077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/11/2016] [Indexed: 02/04/2023] Open
Abstract
There is emerging evidence that exocytosis plays an important role in regulating T cell receptor (TCR) signaling. The trafficking molecules involved in lytic granule (LG) secretion in cytotoxic T lymphocytes (CTL) have been well-studied due to the immune disorder known as familial hemophagocytic lymphohistiocytosis (FHLH). However, the knowledge of trafficking machineries regulating the exocytosis of receptors and signaling molecules remains quite limited. In this review, we summarize the reported trafficking molecules involved in the transport of the TCR and downstream signaling molecules to the cell surface. By combining this information with the known knowledge of LG exocytosis and general exocytic trafficking machinery, we attempt to draw a more complete picture of how the TCR signaling network and exocytic trafficking matrix are interconnected to facilitate T cell activation. This also highlights how membrane compartmentalization facilitates the spatiotemporal organization of cellular responses that are essential for immune functions.
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Affiliation(s)
- Jieqiong Lou
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South WalesSydney, NSW, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydney, NSW, Australia
| | - Jérémie Rossy
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South WalesSydney, NSW, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydney, NSW, Australia
| | - Qiji Deng
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South WalesSydney, NSW, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydney, NSW, Australia
| | - Sophie V Pageon
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South WalesSydney, NSW, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydney, NSW, Australia
| | - Katharina Gaus
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South WalesSydney, NSW, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydney, NSW, Australia
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15
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Thorn P, Zorec R, Rettig J, Keating DJ. Exocytosis in non-neuronal cells. J Neurochem 2016; 137:849-59. [PMID: 26938142 DOI: 10.1111/jnc.13602] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 02/02/2016] [Accepted: 03/01/2016] [Indexed: 12/18/2022]
Abstract
Exocytosis is the process by which stored neurotransmitters and hormones are released via the fusion of secretory vesicles with the plasma membrane. It is a dynamic, rapid and spatially restricted process involving multiple steps including vesicle trafficking, tethering, docking, priming and fusion. For many years great steps have been undertaken in our understanding of how exocytosis occurs in different cell types, with significant focus being placed on synaptic release and neurotransmission. However, this process of exocytosis is an essential component of cell signalling throughout the body and underpins a diverse array of essential physiological pathways. Many similarities exist between different cell types with regard to key aspects of the exocytosis pathway, such as the need for Ca(2+) to trigger it or the involvement of members of the N-ethyl maleimide-sensitive fusion protein attachment protein receptor protein families. However, it is also equally clear that non-neuronal cells have acquired highly specialized mechanisms to control the release of their own unique chemical messengers. This review will focus on several important non-neuronal cell types and discuss what we know about the mechanisms they use to control exocytosis and how their specialized output is relevant to the physiological role of each individual cell type. These include enteroendocrine cells, pancreatic β cells, astrocytes, lactotrophs and cytotoxic T lymphocytes. Non-neuronal cells have acquired highly specialized mechanisms to control the release of unique chemical messengers, such as polarised fusion of insulin granules in pancreatic β cells targeted towards the vasculature (top). This review discusses mechanisms used in several important non-neuronal cell types to control exocytosis, and the relevance of intermediate vesicle fusion pore states (bottom) and their specialized output to the physiological role of each cell type. These include enteroendocrine cells, pancreatic β cells, astrocytes, lactotrophs and cytotoxic T lymphocytes. This article is part of a mini review series on Chromaffin cells (ISCCB Meeting, 2015).
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Affiliation(s)
- Peter Thorn
- Charles Perkins Centre, John Hopkins Drive, The University of Sydney, Camperdown, NSW, Australia
| | - Robert Zorec
- Laboratory of Neuroendocrinology and Molecular Cell Physiology, Institute of Pathophysiology, University of Ljubljana, Faculty of Medicine, Ljubljana, Slovenia.,Celica Biomedical, Ljubljana, Slovenia
| | - Jens Rettig
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
| | - Damien J Keating
- Department of Human Physiology and Centre for Neuroscience, Flinders University, Adelaide, SA, Australia.,South Australian Health and Medical Research Institute (SAHMRI), Adelaide, Australia
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16
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Bhat R, Bhattacharyya PK, Ratech H. An Immunohistochemical Survey of SNARE Proteins Shows Distinct Patterns of Expression in Hematolymphoid Neoplasia. Am J Clin Pathol 2016; 145:604-16. [PMID: 27247366 DOI: 10.1093/ajcp/aqw022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Five proteins from the soluble N-ethylmaleimide-sensitive factor activating protein receptor (SNARE) complex family were studied in normal hematopoietic cells in bone marrow; normal lymphocytes at different stages of maturation and differentiation in bone marrow, thymus, tonsil, and lymph node; malignant lymphomas; and leukemias. METHODS Sixty-eight reactive and 380 hematopoietic and lymphoid neoplasms were immunohistochemically stained for syntaxin 7 (STX7), vesicle-associated membrane proteins (VAMP2, VAMP7, VAMP8), and synaptosomal-associated protein 23 (SNAP23). RESULTS STX7 has potential for being a useful marker for distinguishing between normal B precursors (hematogones) vs B lymphoblasts, as well as between the "popcorn" cells of nodular lymphocyte-predominant Hodgkin lymphoma vs the Reed-Sternberg cells of classic Hodgkin lymphoma or the B cells of T-cell, histiocyte-rich B-cell lymphoma. VAMP2 is uniquely expressed by both reactive and malignant plasma cells, in contrast to B-cell non-Hodgkin lymphoma. There is differential expression of SNARE proteins in normal and neoplastic lymphoid tissue depending on lymphocyte maturation stage. CONCLUSIONS Differential SNARE protein expression in the lymphoid system may have potential use in diagnosis and may offer clues to lymphoma biology. VAMP2 is a promising new plasma cell marker.
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Affiliation(s)
- Rekha Bhat
- From the Department of Pathology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY
| | | | - Howard Ratech
- From the Department of Pathology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY
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17
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Bhat SS, Friedmann KS, Knörck A, Hoxha C, Leidinger P, Backes C, Meese E, Keller A, Rettig J, Hoth M, Qu B, Schwarz EC. Syntaxin 8 is required for efficient lytic granule trafficking in cytotoxic T lymphocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:1653-64. [PMID: 27094127 DOI: 10.1016/j.bbamcr.2016.04.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 03/23/2016] [Accepted: 04/14/2016] [Indexed: 12/21/2022]
Abstract
Cytotoxic T lymphocytes (CTL) eliminate pathogen-infected and cancerous cells mainly by polarized secretion of lytic granules (LG, containing cytotoxic molecules like perforin and granzymes) at the immunological synapse (IS). Members of the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) family are involved in trafficking (generation, transport and fusion) of vesicles at the IS. Syntaxin 8 (Stx8) is expressed in LG and colocalizes with the T cell receptor (TCR) upon IS formation. Here, we report the significance of Stx8 for human CTL cytotoxicity. We found that Stx8 mostly localized in late, recycling endosomal and lysosomal compartments with little expression in early endosomal compartments. Down-regulation of Stx8 by siRNA resulted in reduced cytotoxicity. We found that following perforin release of the pre-existing pool upon target cell contact, Stx8 down-regulated CTL regenerate perforin pools less efficiently and thus release less perforin compared to control CTL. CD107a degranulation, real-time and end-point population cytotoxicity assays, and high resolution microscopy support our conclusion that Stx8 is required for proper and timely sorting and trafficking of cytotoxic molecules to functional LG through the endosomal pathway in human CTL.
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Affiliation(s)
- Shruthi S Bhat
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Kim S Friedmann
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Arne Knörck
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Cora Hoxha
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Petra Leidinger
- Human Genetics, School of Medicine, Saarland University, Building 60, 66421 Homburg, Germany.
| | - Christina Backes
- Center for Bioinformatics, Saarland University, Building E2.1, 66123 Saarbrücken, Germany.
| | - Eckart Meese
- Human Genetics, School of Medicine, Saarland University, Building 60, 66421 Homburg, Germany.
| | - Andreas Keller
- Center for Bioinformatics, Saarland University, Building E2.1, 66123 Saarbrücken, Germany.
| | - Jens Rettig
- Physiology, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Markus Hoth
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
| | - Eva C Schwarz
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Building 48, 66421 Homburg, Germany.
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18
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Verboogen DR, Dingjan I, Revelo NH, Visser LJ, ter Beest M, van den Bogaart G. The dendritic cell side of the immunological synapse. Biomol Concepts 2016; 7:17-28. [DOI: 10.1515/bmc-2015-0028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/18/2015] [Indexed: 12/19/2022] Open
Abstract
AbstractImmune responses are initiated by the interactions between antigen-presenting cells (APCs), such as dendritic cells (DCs), with responder cells, such as T cells, via a tight cellular contact interface called the immunological synapse. The immunological synapse is a highly organized subcellular structure that provides a platform for the presentation of antigen in major histocompatibility class I and II complexes (MHC class I and II) on the surface of the APC to receptors on the surface of the responder cells. In T cells, these contacts lead to highly polarized membrane trafficking that results in the local release of lytic granules and in the delivery and recycling of T cell receptors at the immunological synapse. Localized trafficking also occurs at the APC side of the immunological synapse, especially in DCs where antigen loaded in MHC class I and II is presented and cytokines are released specifically at the synapse. Whereas the molecular mechanisms underlying polarized membrane trafficking at the T cell side of the immunological synapse are increasingly well understood, these are still very unclear at the APC side. In this review, we discuss the organization of the APC side of the immunological synapse. We focus on the directional trafficking and release of membrane vesicles carrying MHC molecules and cytokines at the immunological synapses of DCs. We hypothesize that the specific delivery of MHC and the release of cytokines at the immunological synapse mechanistically resemble that of lytic granule release from T cells.
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Affiliation(s)
- Danielle R.J. Verboogen
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Ilse Dingjan
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Natalia H. Revelo
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Linda J. Visser
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Martin ter Beest
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Geert van den Bogaart
- 1Department of Tumor Immunology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
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19
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Dieckmann NMG, Hackmann Y, Aricò M, Griffiths GM. Munc18-2 is required for Syntaxin 11 Localization on the Plasma Membrane in Cytotoxic T-Lymphocytes. Traffic 2015; 16:1330-41. [PMID: 26771955 PMCID: PMC4791091 DOI: 10.1111/tra.12337] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 09/21/2015] [Accepted: 09/21/2015] [Indexed: 12/31/2022]
Abstract
Cytotoxic T‐lymphocytes (CTL) kill their targets by cytolytic granule secretion at the immunological synapse. The Sec/Munc protein, Munc18‐2, and its binding partner Syntaxin 11 (STX11) are both required for granule secretion, with mutations in either leading to the primary immunodeficiency, Familial Haemophagocytic Lymphohistiocytosis (FHL4 and 5). Understanding how Munc18‐2 and STX11 function in CTL has been hampered by not knowing the endogenous localization of these proteins. Using a novel FHL5 Munc18‐2 mutation that results in loss of protein, cytotoxicity and degranulation together with CTL from an FHL4 patient lacking STX11, enabled us to localize endogenous STX11 and Munc18‐2 in CTL. Munc18‐2 localized predominantly to cytolytic granules with low levels associated with the plasma membrane where STX11 localized. Importantly, while Munc18‐2 localization is unaffected by the absence of STX11 in FHL4 CTL, STX11 is lost from the plasma membrane in FHL5 CTL lacking Munc18‐2. These findings support a role for Munc18‐2 in chaperoning STX11 to the plasma membrane where the final fusion events involved in secretion occur.
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Affiliation(s)
- Nele M G Dieckmann
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0XY, United Kingdom
| | - Yvonne Hackmann
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0XY, United Kingdom.,Current address: Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Maurizio Aricò
- Azienda Sanitaria Provinciale 7, Piazza Igea 1, I-97100, Ragusa, Italy
| | - Gillian M Griffiths
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0XY, United Kingdom
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20
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A critical role for alpha-synuclein in development and function of T lymphocytes. Immunobiology 2015; 221:333-40. [PMID: 26517968 DOI: 10.1016/j.imbio.2015.10.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 10/15/2015] [Indexed: 12/24/2022]
Abstract
Alpha-synuclein is highly expressed in the central nervous system and plays an important role in pathogenesis of neurodegenerative disorders such as Parkinson's disease and Lewy body dementia. Previous studies have demonstrated the expression of α-synuclein in hematopoietic elements and peripheral blood mononuclear cells, although its roles in hematopoiesis and adaptive immunity are not studied. Using an α-synuclein knock out (KO) mouse model, we have recently shown that α-synuclein deficiency is associated with a mild defect in late stages of hematopoiesis. More importantly, we demonstrated a marked defect in B lymphocyte development and IgG, but not IgM production in these mice. Here we show a marked defect in development of T lymphocytes in α-synuclein KO mice demonstrated by a significant increase in the number of CD4 and CD8 double negative thymocytes and significant decreases in the number of CD4 single positive and CD8 single positive T cells. This resulted in markedly reduced peripheral T lymphocytes. Interestingly, splenic CD4(+) and CD8(+) T cells that developed in α-synuclein KO mice had a hyperactivated state with higher expression of early activation markers and increased IL-2 production. Moreover, splenic CD4(+) T cells from α-synuclein KO mice produced lower levels of IL-4 upon antigenic stimulation suggesting a defective Th2 differentiation. Our data demonstrate an important role for α-synuclein in development of T lymphocytes and regulation of their phenotype and function.
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21
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Marshall MR, Pattu V, Halimani M, Maier-Peuschel M, Müller ML, Becherer U, Hong W, Hoth M, Tschernig T, Bryceson YT, Rettig J. VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity. J Cell Biol 2015; 210:135-51. [PMID: 26124288 PMCID: PMC4493996 DOI: 10.1083/jcb.201411093] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 05/22/2015] [Indexed: 12/23/2022] Open
Abstract
VAMP8 is associated with the recycling endosome compartment rather than with cytotoxic granules and is required for a fusion step between recycling endosomes and the plasma membrane that brings syntaxin-11 to the immune synapse for cytotoxic granule exocytosis. Cytotoxic T lymphocytes (CTLs) eliminate infected and neoplastic cells through directed release of cytotoxic granule contents. Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic. VAMP8 was posited to represent the cytotoxic granule vesicular SNARE protein mediating exocytosis in mice. In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes. Upon stimulation, these endosomes rapidly trafficked to and fused with the plasma membrane, preceding fusion of cytotoxic granules. Knockdown of VAMP8 blocked both recycling endosome and cytotoxic granule fusion at immune synapses, without affecting activating signaling. Mechanistically, VAMP8-dependent recycling endosomes deposited syntaxin-11 at immune synapses, facilitating assembly of plasma membrane SNARE complexes for cytotoxic granule fusion. Hence, cytotoxic granule exocytosis is a sequential, multivesicle fusion process requiring VAMP8-mediated recycling endosome fusion before cytotoxic granule fusion. Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated.
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Affiliation(s)
- Misty R Marshall
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany Department of Medicine, Center For Infectious Medicine, 14186 Stockholm, Sweden
| | - Varsha Pattu
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Mahantappa Halimani
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany Department of Pathology, Brigham and Woman's Hospital, Boston, MA
| | - Monika Maier-Peuschel
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Martha-Lena Müller
- Department of Medicine, Center For Infectious Medicine, 14186 Stockholm, Sweden
| | - Ute Becherer
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
| | - Wanjin Hong
- Membrane Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 138673
| | - Markus Hoth
- Department of Biophysics, Saarland University, 66421 Homburg, Germany
| | - Thomas Tschernig
- Department of Anatomy, Saarland University, 66421 Homburg, Germany
| | - Yenan T Bryceson
- Department of Medicine, Center For Infectious Medicine, 14186 Stockholm, Sweden
| | - Jens Rettig
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany
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22
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Yang M, Ye L, Wang B, Gao J, Liu R, Hong J, Wang W, Gu W, Ning G. Decreased miR-146 expression in peripheral blood mononuclear cells is correlated with ongoing islet autoimmunity in type 1 diabetes patients 1miR-146. J Diabetes 2015; 7:158-65. [PMID: 24796653 DOI: 10.1111/1753-0407.12163] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/26/2014] [Accepted: 04/27/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Type 1 diabetes mellitus (T1D) is a common autoimmune disease mediated by autoimmune attack against pancreatic β-cells. It has been reported that dysregulation of microRNAs (miRNAs) may contribute to the pathogenesis of autoimmune diseases, including T1D. The aim of the present study was to identify pathogenic miRNAs in peripheral blood mononuclear cells (PBMC) of T1D patients. METHODS Global miRNA and mRNA expression was profiled in PBMC from 12 patients with newly diagnosed T1D and 10 normal controls. Differently expressed miRNAs were validated in an independent set of patients and controls. The dynamic changes in miRNA and target gene expression were analyzed in T1D patients treated with either a short (6 months) or long (12-24 months) course of insulin. The association between miRNA expression and serum glutamic acid decarboxylase antibody (GADA) titers was also investigated. RESULTS Compared with normal controls, there were 26 miRNAs and 1218 genes differently expressed in PBMC of patients with newly diagnosed T1D. The greatest downregulation was for miR-146a (48% decrease; P < 0.05). Expression of its target genes, predicted to be tumor necrosis factor receptor-associated factor 6 (TRAF6), B cell CLL/lymphoma 11A (BCL11A), syntaxin 3 (STX3) and numb homolog (NUMB), was upregulated. Moreover, T1D patients on long-course insulin and optimized glucose control had sustained low expression of miR-146. Interestingly, decreased miR-146a expression was significantly associated with high serum GADA titers (P < 0.05). CONCLUSIONS The results suggest that dysregulation of miR-146 expression in PBMC may be associated with the ongoing autoimmune imbalance in T1D patients.
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Affiliation(s)
- Minglan Yang
- Department of Endocrine and Metabolic Diseases, Ruijin Hospital, School of Medicine, Shanghai Key Laboratory for Endocrine Tumors, Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai JiaoTong University, Shanghai, China
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23
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Golebiewska EM, Harper MT, Williams CM, Savage JS, Goggs R, Fischer von Mollard G, Poole AW. Syntaxin 8 regulates platelet dense granule secretion, aggregation, and thrombus stability. J Biol Chem 2014; 290:1536-45. [PMID: 25404741 PMCID: PMC4340400 DOI: 10.1074/jbc.m114.602615] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Platelet secretion not only drives thrombosis and hemostasis, but also mediates a variety of other physiological and pathological processes. The ubiquitous SNARE machinery and a number of accessory proteins have been implicated in regulating secretion in platelet. Although several platelet SNAREs have been identified, further members of the SNARE family may be needed to fine-tune platelet secretion. In this study we identified expression of the t-SNARE syntaxin 8 (STX8) (Qc SNARE) in mouse and human platelets. In mouse studies, whereas STX8 was not essential for α-granule or lysosome secretion, Stx8−/− platelets showed a significant defect in dense granule secretion in response to thrombin and CRP. This was most pronounced at intermediate concentrations of agonists. They also showed an aggregation defect that could be rescued with exogenous ADP and increased embolization in Stx8−/− mice in vivo consistent with an important autocrine and paracrine role for ADP in aggregation and thrombus stabilization. STX8 therefore specifically contributes to dense granule secretion and represents another member of a growing family of genes that play distinct roles in regulating granule release from platelets and thus platelet function in thrombosis and hemostasis.
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Affiliation(s)
- Ewelina M Golebiewska
- From the School of Physiology and Pharmacology, Medical Sciences Building, University Walk, Bristol BS8 1TD, United Kingdom
| | - Matthew T Harper
- From the School of Physiology and Pharmacology, Medical Sciences Building, University Walk, Bristol BS8 1TD, United Kingdom
| | - Christopher M Williams
- From the School of Physiology and Pharmacology, Medical Sciences Building, University Walk, Bristol BS8 1TD, United Kingdom
| | - Joshua S Savage
- the School of Cancer Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Robert Goggs
- the Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, and
| | | | - Alastair W Poole
- From the School of Physiology and Pharmacology, Medical Sciences Building, University Walk, Bristol BS8 1TD, United Kingdom,
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24
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Xiao W, Shameli A, Harding CV, Meyerson HJ, Maitta RW. Late stages of hematopoiesis and B cell lymphopoiesis are regulated by α-synuclein, a key player in Parkinson's disease. Immunobiology 2014; 219:836-44. [PMID: 25092570 DOI: 10.1016/j.imbio.2014.07.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 06/26/2014] [Accepted: 07/15/2014] [Indexed: 11/16/2022]
Abstract
α-Synuclein plays a crucial role in Parkinson's disease and dementias defined as synucleinopathies. α-Synuclein is expressed in hematopoietic and immune cells, but its functions in hematopoiesis and immune responses are unknown. We utilized α-synuclein(-/-) (KO) mice to investigate its role in hematopoiesis and B cell lymphopoiesis. We demonstrated hematologic abnormalities including mild anemia, smaller platelets, lymphopenia but relatively normal early hematopoiesis in KO mice compared to wild-type (WT) as measured in hematopoietic stem cells and progenitors of the different cell lineages. However, the absolute number of B220(+)IgM(+) B cells in bone marrow was reduced by 4-fold in KO mice (WT: 104±23×10(5) vs. KO: 27±5×10(5)). B cells were also reduced in KO spleens associated with effacement of splenic and lymph node architecture. KO mice showed reduced total serum IgG but no abnormality in serum IgM was noted. When KO mice were challenged with a T cell-dependent antigen, production of antigen specific IgG1 and IgG2b was abolished, but antigen specific IgM was not different from WT mice. Our study shows hematologic abnormalities including anemia and smaller platelets, reduced B cell lymphopoiesis and defects in IgG production in the absence of α-synuclein. This is the first report to show an important role of α-synuclein late in hematopoiesis, B cell lymphopoiesis and adaptive immune response.
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Affiliation(s)
- Wenbin Xiao
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH, United States; Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Afshin Shameli
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH, United States; Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Clifford V Harding
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH, United States; Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Howard J Meyerson
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH, United States; Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Robert W Maitta
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH, United States; Case Western Reserve University School of Medicine, Cleveland, OH, United States.
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25
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Halimani M, Pattu V, Marshall MR, Chang HF, Matti U, Jung M, Becherer U, Krause E, Hoth M, Schwarz EC, Rettig J. Syntaxin11 serves as a t‐
SNARE
for the fusion of lytic granules in human cytotoxic
T
lymphocytes. Eur J Immunol 2013; 44:573-84. [DOI: 10.1002/eji.201344011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/07/2013] [Accepted: 11/06/2013] [Indexed: 11/11/2022]
Affiliation(s)
| | - Varsha Pattu
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Misty R. Marshall
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Hsin Fang Chang
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Ulf Matti
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Martin Jung
- Institut für BiochemieUniversität des Saarlandes Homburg/Saar Germany
| | - Ute Becherer
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Elmar Krause
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
| | - Markus Hoth
- Institut für BiophysikUniversität des Saarlandes Homburg/Saar Germany
| | - Eva C. Schwarz
- Institut für BiophysikUniversität des Saarlandes Homburg/Saar Germany
| | - Jens Rettig
- Institut für PhysiologieUniversität des Saarlandes Homburg/Saar Germany
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26
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van der Sluijs P, Zibouche M, van Kerkhof P. Late steps in secretory lysosome exocytosis in cytotoxic lymphocytes. Front Immunol 2013; 4:359. [PMID: 24302923 PMCID: PMC3831147 DOI: 10.3389/fimmu.2013.00359] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 10/22/2013] [Indexed: 12/16/2022] Open
Abstract
Natural Killer cells are a subset of cytotoxic lymphocytes that are important in host defense against infections and transformed cells. They exert this function through recognition of target cells by cell surface receptors, which triggers a signaling program that results in a re-orientation of the microtubule organizing center and secretory lysosomes toward the target cell. Upon movement of secretory lysosomes to the plasma membrane and subsequent fusion, toxic proteins are released by secretory lysosomes in the immunological synapse which then enter and kill the target cell. In this minireview we highlight recent progress in our knowledge of late steps in this specialized secretion pathway and address important open questions.
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Affiliation(s)
- Peter van der Sluijs
- Department of Cell Biology, University Medical Center Utrecht , Utrecht , Netherlands
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27
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Gómez-Jaramillo L, Delgado-Pérez L, Reales E, Mora-López F, Mateos RM, García-Poley A, Brieva JA, Campos-Caro A. Syntaxin-4 is implicated in the secretion of antibodies by human plasma cells. J Leukoc Biol 2013; 95:305-12. [DOI: 10.1189/jlb.0113031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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28
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Matti U, Pattu V, Halimani M, Schirra C, Krause E, Liu Y, Weins L, Chang HF, Guzman R, Olausson J, Freichel M, Schmitz F, Pasche M, Becherer U, Bruns D, Rettig J. Synaptobrevin2 is the v-SNARE required for cytotoxic T-lymphocyte lytic granule fusion. Nat Commun 2013; 4:1439. [PMID: 23385584 DOI: 10.1038/ncomms2467] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 01/07/2013] [Indexed: 01/15/2023] Open
Abstract
Cytotoxic T lymphocytes kill virus-infected and tumorigenic target cells through the release of perforin and granzymes via fusion of lytic granules at the contact site, the immunological synapse. It has been postulated that this fusion process is mediated by non-neuronal members of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex protein family. Here, using a synaptobrevin2-monomeric red fluorescence protein knock-in mouse we demonstrate that, surprisingly, the major neuronal v-SNARE synaptobrevin2 is expressed in cytotoxic T lymphocytes and exclusively localized on granzyme B-containing lytic granules. Cleavage of synaptobrevin2 by tetanus toxin or ablation of the synaptobrevin2 gene leads to a complete block of lytic granule exocytosis while leaving upstream events unaffected, identifying synaptobrevin2 as the v-SNARE responsible for the fusion of lytic granules at the immunological synapse.
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Affiliation(s)
- Ulf Matti
- Department of Physiology, Saarland University, Building 59, 66421 Homburg, Germany
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29
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Dudenhöffer-Pfeifer M, Schirra C, Pattu V, Halimani M, Maier-Peuschel M, Marshall MR, Matti U, Becherer U, Dirks J, Jung M, Lipp P, Hoth M, Sester M, Krause E, Rettig J. Different Munc13 isoforms function as priming factors in lytic granule release from murine cytotoxic T lymphocytes. Traffic 2013; 14:798-809. [PMID: 23590328 DOI: 10.1111/tra.12074] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 04/11/2013] [Accepted: 04/16/2013] [Indexed: 01/10/2023]
Abstract
In order to fuse lytic granules (LGs) with the plasma membrane at the immunological synapse, cytotoxic T lymphocytes (CTLs) have to render these LGs fusion-competent through the priming process. In secretory tissues such as brain and neuroendocrine glands, this process is mediated by members of the Munc13 protein family. In human CTLs, mutations in the Munc13-4 gene cause a severe loss in killing efficiency, resulting in familial hemophagocytic lymphohistiocytosis type 3, suggesting a similar role of other Munc13 isoforms in the immune system. Here, we investigate the contribution of different Munc13 isoforms to the priming process of murine CTLs at both the mRNA and protein level. We demonstrate that Munc13-1 and Munc13-4 are the only Munc13 isoforms present in mouse CTLs. Both isoforms rescue the drastical secretion defect of CTLs derived from Munc13-4-deficient Jinx mice. Mobility studies using total internal reflection fluorescence microscopy indicate that Munc13-4 and Munc13-1 are responsible for the priming process of LGs. Furthermore, the domains of the Munc13 protein, which is responsible for functional fusion, could be identified. We conclude from these data that both isoforms of the Munc13 family, Munc13-1 and Munc13-4, are functionally redundant in murine CTLs.
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30
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Lopez JA, Voskoboinik I. Deciphering the syntax of cytotoxic lymphocyte degranulation. Eur J Immunol 2013; 43:46-9. [PMID: 23322694 DOI: 10.1002/eji.201243221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 12/03/2012] [Accepted: 12/10/2012] [Indexed: 11/09/2022]
Abstract
In the killer lymphocyte, the targeted delivery of perforin- and granzyme-containing cytotoxic granules to the immunological synapse is crucial for the eradication of pathogen-infected or transformed targets. This process is achieved through a tightly controlled and highly efficient granule exocytosis pathway. Mutations in the granule trafficking proteins Munc13-4, syntaxin 11, Munc18-2 or Rab27 leads to a fatal lapse of immune surveillance and can be manifested as haemophagocytic lymphohistiocytosis in humans. Elucidation of the role of these proteins in exocytic trafficking is pivotal for our understanding of their role in health and disease. In this issue of the European Journal of Immunology, D'Orlando et al. [Eur. J. Immunol. 2013. 43: 194-208] make an important step in this direction, as they generate and characterise syntaxin 11 deficient mice. Herein, we discuss the role of syntaxin-11 in soluble NSF (N-ethylmaleimide sensitive fusion) attachment protein receptors complex formation leading to cytotoxic lymphocyte degranulation and its importance in maintaining immune homeostasis.
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Affiliation(s)
- Jamie A Lopez
- Cancer Immunology Program, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Australia
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31
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Becherer U, Medart MR, Schirra C, Krause E, Stevens D, Rettig J. Regulated exocytosis in chromaffin cells and cytotoxic T lymphocytes: How similar are they? Cell Calcium 2012; 52:303-12. [DOI: 10.1016/j.ceca.2012.04.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 03/27/2012] [Accepted: 04/09/2012] [Indexed: 10/28/2022]
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