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Harding RJ, Xie Y, Caron NS, Findlay-Black H, Lyu C, Potluri N, Chandrasekaran R, Hayden MR, Leavitt BR, Langbehn DR, Southwell AL. Challenges and advances for huntingtin detection in cerebrospinal fluid: in support of relative quantification. Biomark Res 2025; 13:63. [PMID: 40259428 PMCID: PMC12012996 DOI: 10.1186/s40364-025-00772-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2024] [Accepted: 03/27/2025] [Indexed: 04/23/2025] Open
Abstract
Huntington disease (HD) is a progressive and devastating neurodegenerative disease caused by expansion of a glutamine-coding CAG tract in the huntingtin (HTT) gene above a critical threshold of ~ 35 repeats resulting in expression of mutant HTT (mHTT). A promising treatment approach being tested in clinical trials is HTT lowering, which aims to reduce levels of the mHTT protein. Target engagement of these therapies in the brain are inferred using antibody-based assays that measure mHTT levels in the cerebrospinal fluid (CSF). These levels are typically reported as the absolute concentration of mHTT concentration, derived from a standard curve generated using a single protein standard. However, patient biofluids are a complex milieu containing different mHTT protein species, suggesting that absolute quantitation is challenging. As a result, a single recombinant protein standard may not be sufficient to interpret assay signal as molar mHTT concentration. In this study, we used immunoprecipitation and flow cytometry (IP-FCM) to investigate different factors that influence mHTT detection assay signal. Our results show that HTT protein fragmentation, protein-protein interactions, affinity tag positioning, oligomerization and polyglutamine tract length affect assay signal intensity. These findings indicate that absolute HTT quantitation in heterogeneous biological samples is not possible with current technologies using a single standard protein. We also explore the binding specificity of the MW1 anti-polyglutamine antibody, commonly used in these assays as a mHTT-selective reagent and demonstrate that mHTT binding is preferred but not specific. Furthermore, we find that MW1 depletion of mHTT for quantitation of wildtype HTT is not only incomplete, leaving residual mHTT, but also non-specific, resulting in pull down of some wildtype HTT protein. Based on these observations, we recommend that mHTT detection assays report only relative mHTT quantitation using normalized arbitrary units of assay signal intensity, rather than molar concentrations, in the assessment of central nervous system HTT lowering in ongoing clinical and preclinical studies. Further, we recommend that MW1-depletion not be used as a method for quantifying wildtype HTT protein and that detergent be consistently added to samples during testing.
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Affiliation(s)
- Rachel J Harding
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, M5S 3M2, Canada
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Yuanyun Xie
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA
| | - Nicholas S Caron
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Hailey Findlay-Black
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Caroline Lyu
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7, Canada
| | - Nalini Potluri
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA
| | - Renu Chandrasekaran
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, M5S 3M2, Canada
| | - Michael R Hayden
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Blair R Leavitt
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Douglas R Langbehn
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Amber L Southwell
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA.
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2
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Harding RJ, Xie Y, Caron NS, Findlay-Black H, Lyu C, Potluri N, Chandrasekaran R, Hayden MR, Leavitt BR, Langbehn DR, Southwell AL. Challenges and advances for huntingtin detection in cerebrospinal fluid: in support of relative quantification. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.25.614766. [PMID: 39386513 PMCID: PMC11463412 DOI: 10.1101/2024.09.25.614766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/12/2024]
Abstract
Huntington disease (HD) is a progressive and devastating neurodegenerative disease caused by expansion of a glutamine-coding CAG tract in the huntingtin (HTT) gene above a critical threshold of ~35 repeats resulting in expression of mutant HTT (mHTT). A promising treatment approach being tested in clinical trials is HTT lowering, which aims to reduce levels of the mHTT protein. Target engagement of these therapies in the brain are inferred using antibody-based assays to measure mHTT levels in the cerebrospinal fluid (CSF), which is frequently reported as absolute mHTT concentration based on a monomeric protein standard used to generate a standard curve. However, patient biofluids are a complex milieu of different mHTT protein species, suggesting that absolute quantitation is challenging, and a single, recombinant protein standard may not be sufficient to interpret assay signal as molar mHTT concentration. In this study, we used immunoprecipitation and flow cytometry (IP-FCM) to investigate different factors that influence mHTT detection assay signal. Our results show that HTT protein fragmentation, protein-protein interactions, affinity tag positioning, oligomerization and polyglutamine tract length affect assay signal intensity, indicating that absolute HTT quantitation in heterogeneous biological samples is not possible with current technologies using a single standard protein. We also explore the binding specificity of the MW1 anti-polyglutamine antibody, commonly used in these assays as a mHTT-selective reagent and demonstrate that mHTT binding is preferred but not specific. Furthermore, we find that MW1 depletion is not only incomplete, leaving residual mHTT, but also non-specific, resulting in pull down of some wildtype HTT protein. Based on these observations, we recommend that mHTT detection assays report only relative mHTT quantitation using normalized arbitrary units of assay signal intensity, rather than molar concentrations, in the assessment of central nervous system HTT lowering in ongoing clinical and preclinical studies, and that MW1-depletion not be used a method for quantifying wildtype HTT protein.
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Affiliation(s)
- Rachel J. Harding
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G 1L7, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Yuanyun Xie
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA
| | - Nicholas S. Caron
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC V5Z 4H4 Canada
| | - Hailey Findlay-Black
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC V5Z 4H4 Canada
| | - Caroline Lyu
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Nalini Potluri
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA
| | - Renu Chandrasekaran
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC V5Z 4H4 Canada
| | - Blair R. Leavitt
- Centre for Molecular Medicine and Therapeutics, The University of British Columbia, Vancouver, BC V5Z 4H4 Canada
| | - Douglas R. Langbehn
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Amber L. Southwell
- Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL, 32827, USA
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3
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Wang Y, Li Y, Cao J, Yang X, Huang J, Huang M, Gu S. Research Progress of Fluorescent Probes for Detection of Glutathione (GSH): Fluorophore, Photophysical Properties, Biological Applications. Molecules 2024; 29:4333. [PMID: 39339330 PMCID: PMC11434280 DOI: 10.3390/molecules29184333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2024] [Revised: 08/26/2024] [Accepted: 09/03/2024] [Indexed: 09/30/2024] Open
Abstract
Intracellular biothiols, including cysteine (Cys), glutathione (GSH), and homocysteine (Hcy), play a critical role in many physiological and pathological processes. Among them, GSH is the most abundant non-protein mercaptan (1-10 mM) in cells, and the change in GSH concentration level is closely related to the occurrence of many diseases, such as Parkinson's disease, Alzheimer's disease, and neurological diseases. Fluorescent probes have attracted much attention due to their advantages of high specificity, high sensitivity, high selectivity, low cost, and high quantum yield. Methods that use optical probes for selective detection of GSH in vitro and in vivo are in high demand. In this paper, we reviewed the most recent five years of research on fluorescence probes for the detection of GSH, including the specific detection of GSH, dual-channel identification of GSH and other substances, and the detection of GSH and other biothiols. According to the type of fluorophore, we classified GSH fluorescent probes into eight classes, including BODIPY, 1,8-Naphthalimide, coumarin, xanthene, rhodamine, cyanine, benzothiazoles, and others. In addition, we roundly discuss the synthesis, detection mechanism, photophysical properties, and biological applications of fluorescent probes. We hope that this review will inspire the exploration of new fluorescent probes for GSH and other related analyses.
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Affiliation(s)
- Yao Wang
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
| | - Yanfei Li
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
| | - Jinbo Cao
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
- Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou 511400, China
| | - Xiyan Yang
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
| | - Jiaxiang Huang
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
| | - Mingyue Huang
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
| | - Shaobin Gu
- Henan International Joint Laboratory of Food Green Processing and Quality Safety Control, College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China; (Y.L.); (J.C.); (X.Y.); (J.H.); (M.H.)
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Ozono T, Kimura Y, Suenaga T, Beck G, Jinno J, Aguirre C, Ikenaka K, Krainc D, Mochizuki H, Arase H. Extracellular transportation of α-synuclein by HLA class II molecules. Biochem Biophys Res Commun 2023; 644:25-33. [PMID: 36621149 DOI: 10.1016/j.bbrc.2022.12.082] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 12/28/2022] [Indexed: 01/02/2023]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the progressive accumulation of α-synuclein aggregates in form of Lewy bodies. Genome-wide association studies have revealed that human leukocyte antigen (HLA) class II is a PD-associated gene, although the mechanisms linking HLA class II and PD remain elusive. Here, we identified a novel function of HLA class II in the transport of intracellular α-synuclein to the outside of cells. HLA class II molecules and α-synuclein formed complexes and moved to the cell surface at various degrees among HLA-DR alleles. HLA-DR with a DRB5∗01:01 allele, a putative PD-risk allele, substantially translocated normal and conformationally abnormal α-synuclein to the cell surface and extracellular vesicles. α-Synuclein/HLA class II complexes were found in A2058 melanoma cells, which express intrinsic α-synuclein and HLA-DR with DRB5∗01:01. Our findings will expand our knowledge of unconventional HLA class II function from autoimmune diseases to neurodegenerative disorders, shedding light on the association between the GWAS-prioritized PD-risk gene HLA-DR and α-synuclein.
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Affiliation(s)
- Tatsuhiko Ozono
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan; Laboratory of Immunochemistry, Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yasuyoshi Kimura
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Tadahiro Suenaga
- Laboratory of Immunochemistry, Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan; Department of Immunochemistry, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan; Department of Immunology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan
| | - Goichi Beck
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Jyunki Jinno
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - César Aguirre
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Kensuke Ikenaka
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Hideki Mochizuki
- Department of Neurology, Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Hisashi Arase
- Laboratory of Immunochemistry, Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan; Department of Immunochemistry, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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5
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Tsai K, Ma C, Han X, Allaire J, Healey GR, Crowley SM, Yu H, Jacobson K, Xia L, Priatel JJ, Vallance BA. Highly Sensitive, Flow Cytometry-Based Measurement of Intestinal Permeability in Models of Experimental Colitis. Cell Mol Gastroenterol Hepatol 2023; 15:425-438. [PMID: 36244647 PMCID: PMC9791122 DOI: 10.1016/j.jcmgh.2022.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/06/2022] [Accepted: 10/07/2022] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Increased intestinal permeability is seen in a variety of inflammatory conditions such as enteric infections and inflammatory bowel disease. Because barrier function can provide a key biomarker of disease severity, it often is assayed in animal models. A common methodology involves gavaging mice with fluorescein isothiocyanate-conjugated dextran (FITC-D), followed by cardiac puncture to assay plasma fluorescence on a spectrophotometer. Although the FITC-D method is relatively simple, its sensitivity is limited and enables only a single measurement because the test requires killing the subject. Herein, we describe a novel flow cytometry-based method of intestinal permeability measurement based on detection of orally gavaged ovalbumin (OVA) that leaks out of the gut. Our approach uses minute blood volumes collected from the tail vein, permitting repeated testing of the same subject at multiple time points. By comparing this assay against the gold standard FITC-D method, we show the expanded utility of our OVA assay in measuring intestinal permeability. METHODS We directly compared our OVA assay against the FITC-D assay by co-administering both probes orally to the same animals and subsequently using their respective methodologies to measure intestinal permeability by detecting probe levels in the plasma. Permeability was assessed in mice genetically deficient in intestinal mucus production or glycosylation. In addition, wild-type mice undergoing dextran sodium sulfate-induced colitis or infected by the enteric bacterial pathogen Citrobacter rodentium also were tested. RESULTS The OVA assay showed very high efficacy in all animal models of intestinal barrier dysfunction tested. Besides identifying intestinal barrier dysfunction in mice with impaired mucin glycosylation, the assay also allowed for repeated tracking of intestinal permeability within the same animal over time, providing data that cannot be easily acquired with other currently applied methods. CONCLUSIONS The OVA assay is a highly sensitive and effective method of measuring intestinal permeability in mouse models of barrier dysfunction and experimental colitis.
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Affiliation(s)
- Kevin Tsai
- British Columbia Children's Hospital Research Institute, Vancouver, British Columbia, Canada; Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Caixia Ma
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiao Han
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joannie Allaire
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Genelle R Healey
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shauna M Crowley
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hongbing Yu
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kevan Jacobson
- British Columbia Children's Hospital Research Institute, Vancouver, British Columbia, Canada; Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lijun Xia
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma
| | - John J Priatel
- British Columbia Children's Hospital Research Institute, Vancouver, British Columbia, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Bruce A Vallance
- British Columbia Children's Hospital Research Institute, Vancouver, British Columbia, Canada; Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
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6
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Teixeiro E, Daniels MA. In Vitro Analysis of Thymocyte Signaling. Methods Mol Biol 2023; 2580:303-313. [PMID: 36374466 DOI: 10.1007/978-1-0716-2740-2_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
When a developing thymocyte expresses a TCR, it is subjected to numerous interactions with self-peptide/MHC complexes that determine its fate. These include death by neglect, negative selection (apoptosis and lineage deviation), positive selection, and lineage commitment. Identifying signals that govern these unique cell fates requires the ability to assess the activity, level of expression, subcellular location, and molecular associations between numerous proteins within the developing T cell. Given the unique, temporal, and developmental changes that occur during development, isolating and analyzing small populations of thymocytes are necessary to get a complete picture of the development process. Thus, this chapter describes methods designed to analyze thymocyte signaling under various types of peptide-based stimulation in vitro.
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Affiliation(s)
- Emma Teixeiro
- Department of Molecular Microbiology and Immunology, NextGen Precision Health, University of Missouri, Columbia, MO, USA
| | - Mark A Daniels
- Department of Molecular Microbiology and Immunology, NextGen Precision Health, University of Missouri, Columbia, MO, USA.
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7
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Teixeiro E, Daniels MA. Fetal Thymic Organ Culture and Negative Selection. Methods Mol Biol 2023; 2580:293-302. [PMID: 36374465 DOI: 10.1007/978-1-0716-2740-2_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Negative selection removes potentially harmful T cell precursors from the conventional T cell pool. This process can involve the induction of apoptosis, anergy, receptor editing, or deviation into a regulatory T cell lineage. As such, this process is essential for the health of an organism through its contribution to central and peripheral tolerance. While a great deal is known about the process, the precise mechanisms that regulate these various forms of negative selection are not clear. Numerous models exist with the potential to address these questions in vitro and in vivo. This chapter describes fetal thymic organ culture methods designed to analyze the signals that determine these unique cell fates.
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Affiliation(s)
- Emma Teixeiro
- Department of Molecular Microbiology and Immunology, NextGen Precision Health, University of Missouri, Columbia, MO, USA
| | - Mark A Daniels
- Department of Molecular Microbiology and Immunology, NextGen Precision Health, University of Missouri, Columbia, MO, USA.
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Mørch AM, Schneider F, Jenkins E, Santos AM, Fraser SE, Davis SJ, Dustin ML. The kinase occupancy of T cell coreceptors reconsidered. Proc Natl Acad Sci U S A 2022; 119:e2213538119. [PMID: 36454761 PMCID: PMC9894195 DOI: 10.1073/pnas.2213538119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/01/2022] [Indexed: 12/05/2022] Open
Abstract
The sensitivity of the αβ T cell receptor (TCR) is enhanced by the coreceptors CD4 and CD8αβ, which are expressed primarily by cells of the helper and cytotoxic T cell lineages, respectively. The coreceptors bind to major histocompatibility complex (MHC) molecules and associate intracellularly with the Src-family kinase Lck, which catalyzes TCR phosphorylation during receptor triggering. Although coreceptor/kinase occupancy was initially believed to be high, a recent study suggested that most coreceptors exist in an Lck-free state, and that this low occupancy helps to effect TCR antigen discrimination. Here, using the same method, we found instead that the CD4/Lck interaction was stoichiometric (~100%) and that the CD8αβ/Lck interaction was substantial (~60%). We confirmed our findings in live cells using fluorescence cross-correlation spectroscopy (FCCS) to measure coreceptor/Lck codiffusion in situ. After introducing structurally guided mutations into the intracellular domain of CD4, we used FCCS to also show that stoichiometric coupling to Lck required an amphipathic α-helix present in CD4 but not CD8α. In double-positive cells expressing equal numbers of both coreceptors, but limiting amounts of kinase, CD4 outcompeted CD8αβ for Lck. In T cells, TCR signaling induced CD4/Lck oligomerization but did not affect the high levels of CD4/Lck occupancy. These findings help settle the question of kinase occupancy and suggest that the binding advantages that CD4 has over CD8 could be important when Lck levels are limiting.
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Affiliation(s)
- Alexander M. Mørch
- Kennedy Institute of Rheumatology, University of Oxford, OxfordOX3 7FY, United Kingdom
- Medical Research Council Human Immunology Unit, and Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, OxfordOX3 9DS, United Kingdom
| | - Falk Schneider
- Translational Imaging Center, University of Southern California, Los Angeles, CA90089
| | - Edward Jenkins
- Medical Research Council Human Immunology Unit, and Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, OxfordOX3 9DS, United Kingdom
| | - Ana Mafalda Santos
- Medical Research Council Human Immunology Unit, and Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, OxfordOX3 9DS, United Kingdom
| | - Scott E. Fraser
- Translational Imaging Center, University of Southern California, Los Angeles, CA90089
| | - Simon J. Davis
- Medical Research Council Human Immunology Unit, and Medical Research Council Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, OxfordOX3 9DS, United Kingdom
| | - Michael L. Dustin
- Kennedy Institute of Rheumatology, University of Oxford, OxfordOX3 7FY, United Kingdom
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9
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Garcillán B, Megino RF, Herrero-Alonso M, Guardo AC, Perez-Flores V, Juraske C, Idstein V, Martin-Fernandez JM, Geisler C, Schamel WWA, Marin AV, Regueiro JR. The role of the different CD3γ domains in TCR expression and signaling. Front Immunol 2022; 13:978658. [PMID: 36119034 PMCID: PMC9478619 DOI: 10.3389/fimmu.2022.978658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
The CD3 subunits of the T-cell antigen receptor (TCR) play a central role in regulation of surface TCR expression levels. Humans who lack CD3γ (γ—) show reduced surface TCR expression levels and abolished phorbol ester (PMA)-induced TCR down-regulation. The response to PMA is mediated by a double leucine motif in the intracellular (IC) domain of CD3γ. However, the molecular cause of the reduced TCR surface expression in γ— lymphocytes is still not known. We used retroviral vectors carrying wild type CD3γ or CD3δ or the following chimeras (EC-extracellular, TM-transmembrane and IC): δECγTMγIC (δγγ for short), γγδ, γδδ and γγ-. Expression of γγγ, γγδ, γδδ or γγ- in the γ— T cell line JGN, which lacks surface TCR, demonstrated that cell surface TCR levels in JGN were dependent on the EC domain of CD3γ and could not be replaced by the one of CD3δ. In JGN and primary γ— patient T cells, the tested chimeras confirmed that the response to PMA maps to the IC domain of CD3γ. Since protein homology explains these results better than domain structure, we conclude that CD3γ contributes conformational cues that improve surface TCR expression, likely at the assembly or membrane transport steps. In JGN cells all chimeric TCRs were signalling competent. However, an IC domain at CD3γ was required for TCR-induced IL-2 and TNF-α production and CD69 expression, indicating that a TCR without a CD3γ IC domain has altered signalling capabilities.
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Affiliation(s)
- Beatriz Garcillán
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Rebeca F. Megino
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Marta Herrero-Alonso
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Alberto C. Guardo
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Veronica Perez-Flores
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Claudia Juraske
- Signaling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
- Department of Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Centre for Chronic Immunodeficiency (CCI), Medical Center Freiburg and Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
| | - Vincent Idstein
- Signaling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
- Department of Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Centre for Chronic Immunodeficiency (CCI), Medical Center Freiburg and Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
| | - Jose M. Martin-Fernandez
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Carsten Geisler
- The LEO Foundation Skin Immunology Research Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Wolfgang W. A. Schamel
- Signaling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
- Department of Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Centre for Chronic Immunodeficiency (CCI), Medical Center Freiburg and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ana V. Marin
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Jose R. Regueiro
- Department of Immunology, Ophthalmology and Ear, Nose and Throat (ENT), Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
- *Correspondence: Jose R. Regueiro,
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10
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Lynch CA, Guo Y, Mei A, Kreisel D, Gelman AE, Jacobsen EA, Krupnick AS. Solving the Conundrum of Eosinophils in Alloimmunity. Transplantation 2022; 106:1538-1547. [PMID: 34966103 PMCID: PMC9234098 DOI: 10.1097/tp.0000000000004030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Eosinophils are bone-marrow-derived granulocytes known for their ability to facilitate clearance of parasitic infections and their association with asthma and other inflammatory diseases. The purpose of this review is to discuss the currently available human observational and animal experimental data linking eosinophils to the immunologic response in solid organ transplantation. First, we present observational human studies that demonstrate a link between transplantation and eosinophils yet were unable to define the exact role of this cell population. Next, we describe published experimental models and demonstrate a defined mechanistic role of eosinophils in downregulating the alloimmune response to murine lung transplants. The overall summary of this data suggests that further studies are needed to define the role of eosinophils in multiple solid organ allografts and points to the possibility of manipulating this cell population to improve graft survival.
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Affiliation(s)
- Cherie Alissa Lynch
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Arizona
| | - Yizhan Guo
- Department of Surgery, University of Maryland, Baltimore Maryland
| | - Alex Mei
- Department of Surgery, University of Maryland, Baltimore Maryland
| | | | | | - Elizabeth A. Jacobsen
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Arizona
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11
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Thapa P, Guyer RS, Yang AY, Parks CA, Brusko TM, Brusko M, Connors TJ, Farber DL. Infant T cells are developmentally adapted for robust lung immune responses through enhanced T cell receptor signaling. Sci Immunol 2021; 6:eabj0789. [PMID: 34890254 PMCID: PMC8765725 DOI: 10.1126/sciimmunol.abj0789] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Infants require coordinated immune responses to prevent succumbing to multiple infectious challenges during early life, particularly in the respiratory tract. The mechanisms by which infant T cells are functionally adapted for these responses are not well understood. Here, we demonstrated using an in vivo mouse cotransfer model that infant T cells generated greater numbers of lung-homing effector cells in response to influenza infection compared with adult T cells in the same host, due to augmented T cell receptor (TCR)–mediated signaling. Mouse infant T cells showed increased sensitivity to low antigen doses, originating at the interface between T cells and antigen-bearing accessory cells—through actin-mediated mobilization of signaling molecules to the immune synapse. This enhanced signaling was also observed in human infant versus adult T cells. Our findings provide a mechanism for how infants control pathogen load and dissemination, which is important for designing developmentally targeted strategies for promoting immune responses at this vulnerable life stage.
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Affiliation(s)
- Puspa Thapa
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York NY 10032
| | - Rebecca S. Guyer
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York NY 10032
| | - Alexander Y. Yang
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York NY 10032
| | - Christopher A. Parks
- Columbia Center for Translational Immunology, Columbia University Irving Medical Center, New York, NY 10032
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032
| | - Todd M. Brusko
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Maigan Brusko
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Thomas J. Connors
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY 10032
| | - Donna L. Farber
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York NY 10032
- Department of Surgery, Columbia University Irving Medical Center, New York, NY 10032
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12
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Horkova V, Drobek A, Mueller D, Gubser C, Niederlova V, Wyss L, King CG, Zehn D, Stepanek O. Dynamics of the Coreceptor-LCK Interactions during T Cell Development Shape the Self-Reactivity of Peripheral CD4 and CD8 T Cells. Cell Rep 2021; 30:1504-1514.e7. [PMID: 32023465 PMCID: PMC7003063 DOI: 10.1016/j.celrep.2020.01.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 05/31/2019] [Accepted: 01/02/2020] [Indexed: 02/07/2023] Open
Abstract
Overtly self-reactive T cells are removed during thymic selection. However, it has been recently established that T cell self-reactivity promotes protective immune responses. Apparently, the level of self-reactivity of mature T cells must be tightly balanced. Our mathematical model and experimental data show that the dynamic regulation of CD4- and CD8-LCK coupling establish the self-reactivity of the peripheral T cell pool. The stoichiometry of the interaction between CD8 and LCK, but not between CD4 and LCK, substantially increases upon T cell maturation. As a result, peripheral CD8+ T cells are more self-reactive than CD4+ T cells. The different levels of self-reactivity of mature CD8+ and CD4+ T cells likely reflect the unique roles of these subsets in immunity. These results indicate that the evolutionary selection pressure tuned the CD4-LCK and CD8-LCK stoichiometries, as they represent the unique parts of the proximal T cell receptor (TCR) signaling pathway, which differ between CD4+ and CD8+ T cells. Coupling of CD8-LCK but not CD4-LCK increases upon T cell maturation Dynamics of coreceptor-LCK coupling stoichiometry establish T cell self-reactivity CD8+ T cells are more self-reactive than CD4+ T cells
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Affiliation(s)
- Veronika Horkova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, 14220 Prague, Czech Republic
| | - Ales Drobek
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, 14220 Prague, Czech Republic
| | - Daniel Mueller
- Department of Biomedicine, University Hospital and University of Basel, 4031 Basel, Switzerland
| | - Celine Gubser
- Department of Biomedicine, University Hospital and University of Basel, 4031 Basel, Switzerland; Peter Doherty Institute, University of Melbourne, Melbourne, Australia
| | - Veronika Niederlova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, 14220 Prague, Czech Republic
| | - Lena Wyss
- Department of Biomedicine, University Hospital and University of Basel, 4031 Basel, Switzerland; Institute for Immunology, Biomedical Center (BMC) Munich, Ludwig-Maximilians-University, Munich, Germany
| | - Carolyn G King
- Department of Biomedicine, University Hospital and University of Basel, 4031 Basel, Switzerland
| | - Dietmar Zehn
- Division of Animal Physiology and Immunology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Ondrej Stepanek
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, 14220 Prague, Czech Republic.
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13
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Wei Q, Brzostek J, Sankaran S, Casas J, Hew LSQ, Yap J, Zhao X, Wojciech L, Gascoigne NRJ. Lck bound to coreceptor is less active than free Lck. Proc Natl Acad Sci U S A 2020; 117:15809-15817. [PMID: 32571924 PMCID: PMC7355011 DOI: 10.1073/pnas.1913334117] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Src family kinase Lck plays critical roles during T cell development and activation, as it phosphorylates the TCR/CD3 complex to initiate TCR signaling. Lck is present either in coreceptor-bound or coreceptor-unbound (free) forms, and we here present evidence that the two pools of Lck have different molecular properties. We discovered that the free Lck fraction exhibited higher mobility than CD8α-bound Lck in OT-I T hybridoma cells. The free Lck pool showed more activating Y394 phosphorylation than the coreceptor-bound Lck pool. Consistent with this, free Lck also had higher kinase activity, and free Lck mediated higher T cell activation as compared to coreceptor-bound Lck. Furthermore, the coreceptor-Lck coupling was independent of TCR activation. These findings give insights into the initiation of TCR signaling, suggesting that changes in coreceptor-Lck coupling constitute a mechanism for regulation of T cell sensitivity.
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Affiliation(s)
- Qianru Wei
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Joanna Brzostek
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Shvetha Sankaran
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
- Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore, 117456
| | - Javier Casas
- Department of Biochemistry, Molecular Biology and Physiology, Universidad de Valladolid, Valladolid, Spain, 47005
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas, Universidad de Valladolid, Valladolid, Spain, 47003
| | - Lois Shi-Qi Hew
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Jiawei Yap
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Xiang Zhao
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Lukasz Wojciech
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545
| | - Nicholas R J Gascoigne
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545;
- Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore, 117456
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14
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Brown EA, Neier SC, Neuhauser C, Schrum AG, Smith SEP. Quantification of Protein Interaction Network Dynamics using Multiplexed Co-Immunoprecipitation. J Vis Exp 2019. [PMID: 31498315 DOI: 10.3791/60029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Dynamic protein-protein interactions control cellular behavior, from motility to DNA replication to signal transduction. However, monitoring dynamic interactions among multiple proteins in a protein interaction network is technically difficult. Here, we present a protocol for Quantitative Multiplex Immunoprecipitation (QMI), which allows quantitative assessment of fold changes in protein interactions based on relative fluorescence measurements of Proteins in Shared Complexes detected by Exposed Surface epitopes (PiSCES). In QMI, protein complexes from cell lysates are immunoprecipitated onto microspheres, and then probed with a labeled antibody for a different protein in order to quantify the abundance of PiSCES. Immunoprecipitation antibodies are conjugated to different MagBead spectral regions, which allows a flow cytometer to differentiate multiple parallel immunoprecipitations and simultaneously quantify the amount of probe antibody associated with each. QMI does not require genetic tagging and can be performed using minimal biomaterial compared to other immunoprecipitation methods. QMI can be adapted for any defined group of interacting proteins, and has thus far been used to characterize signaling networks in T cells and neuronal glutamate synapses. Results have led to new hypothesis generation with potential diagnostic and therapeutic applications. This protocol includes instructions to perform QMI, from the initial antibody panel selection through to running assays and analyzing data. The initial assembly of a QMI assay involves screening antibodies to generate a panel, and empirically determining an appropriate lysis buffer. The subsequent reagent preparation includes covalently coupling immunoprecipitation antibodies to MagBeads, and biotinylating probe antibodies so they can be labeled by a streptavidin-conjugated fluorophore. To run the assay, lysate is mixed with MagBeads overnight, and then beads are divided and incubated with different probe antibodies, and then a fluorophore label, and read by flow cytometry. Two statistical tests are performed to identify PiSCES that differ significantly between experimental conditions, and results are visualized using heatmaps or node-edge diagrams.
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Affiliation(s)
- Emily A Brown
- Center for Integrative Brain Research, Seattle Children's Research Institute; Graduate Program in Neuroscience, University of Washington
| | - Steven C Neier
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School; Broad Institute of Harvard and MIT
| | | | - Adam G Schrum
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri; Department of Surgery, School of Medicine, University of Missouri; Department Bioengineering, College of Engineering, University of Missouri
| | - Stephen E P Smith
- Center for Integrative Brain Research, Seattle Children's Research Institute; Graduate Program in Neuroscience, University of Washington; Department of Pediatrics, University of Washington;
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15
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Onyema OO, Guo Y, Mahgoub B, Wang Q, Manafi A, Mei Z, Banerjee A, Li D, Stoler MH, Zaidi MT, Schrum AG, Kreisel D, Gelman AE, Jacobsen EA, Krupnick AS. Eosinophils downregulate lung alloimmunity by decreasing TCR signal transduction. JCI Insight 2019; 4:128241. [PMID: 31167966 DOI: 10.1172/jci.insight.128241] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/23/2019] [Indexed: 12/31/2022] Open
Abstract
Despite the accepted notion that granulocytes play a universally destructive role in organ and tissue grafts, it has been recently described that eosinophils can facilitate immunosuppression-mediated acceptance of murine lung allografts. The mechanism of eosinophil-mediated tolerance, or their role in regulating alloimmune responses in the absence of immunosuppression, remains unknown. Using lung transplants in a fully MHC-mismatched BALB/c (H2d) to C57BL/6 (H2b) strain combination, we demonstrate that eosinophils downregulate T cell-mediated immune responses and play a tolerogenic role even in the absence of immunosuppression. We further show that such downregulation depends on PD-L1/PD-1-mediated synapse formation between eosinophils and T cells. We also demonstrate that eosinophils suppress T lymphocyte responses through the inhibition of T cell receptor/CD3 (TCR/CD3) subunit association and signal transduction in an inducible NOS-dependent manner. Increasing local eosinophil concentration, through administration of intratracheal eotaxin and IL-5, can ameliorate alloimmune responses in the lung allograft. Thus, our data indicate that eosinophil mobilization may be utilized as a novel means of lung allograft-specific immunosuppression.
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Affiliation(s)
| | - Yizhan Guo
- Department of Surgery, Carter Center for Immunology, and
| | - Bayan Mahgoub
- Department of Surgery, Carter Center for Immunology, and
| | - Qing Wang
- Department of Surgery, Carter Center for Immunology, and
| | - Amir Manafi
- Department of Surgery, Carter Center for Immunology, and
| | - Zhongcheng Mei
- Department of Surgery, Carter Center for Immunology, and
| | | | - Dongge Li
- Department of Surgery, Carter Center for Immunology, and
| | - Mark H Stoler
- Department of Pathology, University of Virginia, Charlottesville, Virginia, USA
| | - Melissa T Zaidi
- Molecular Microbiology and Immunology, Surgery, Bioengineering, University of Missouri, Columbia, Missouri, USA
| | - Adam G Schrum
- Molecular Microbiology and Immunology, Surgery, Bioengineering, University of Missouri, Columbia, Missouri, USA
| | - Daniel Kreisel
- Department of Surgery, Washington University, St. Louis, Missouri, USA
| | - Andrew E Gelman
- Department of Surgery, Washington University, St. Louis, Missouri, USA
| | - Elizabeth A Jacobsen
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Arizona, USA
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16
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Li X, Koudstaal W, Fletcher L, Costa M, van Winsen M, Siregar B, Inganäs H, Kim J, Keogh E, Macedo J, Holland T, Perry S, Bard F, Hoozemans JJ, Goudsmit J, Apetri A, Pascual G. Naturally occurring antibodies isolated from PD patients inhibit synuclein seeding in vitro and recognize Lewy pathology. Acta Neuropathol 2019; 137:825-836. [PMID: 30805666 PMCID: PMC6482120 DOI: 10.1007/s00401-019-01974-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/24/2022]
Abstract
Deposition of α-synuclein into Lewy bodies and Lewy neurites is the hallmark of Parkinson’s disease (PD). It is hypothesized that α-synuclein pathology spreads by a “prion-like” mechanism (i.e., by seeded aggregation or templated misfolding). Therefore, various extracellular α-synuclein conformers and/or posttranslational modifications may serve as biomarkers of disease or potential targets for novel interventions. To explore whether the antibody repertoires of PD patients contain anti-α-synuclein antibodies that can potentially be used as markers or immunotherapy, we interrogated peripheral IgG+ memory B cells from PD patients for reactivity to α-synuclein. In total, ten somatically mutated antibodies were recovered, suggesting the presence of an ongoing antigen-driven immune response. The three antibodies that had the highest affinity to recombinant full-length α-synuclein, aSyn-323.1, aSyn-336.1 and aSyn-338.1, were characterized further and shown to recognize epitopes in the C terminus of α-synuclein with binding affinities between 0.3 and 2.8 μM. Furthermore, all three antibodies were able to neutralize the “seeding” of intracellular synuclein aggregates in an in vitro α-synuclein seeding assay. Finally, differential reactivities were observed for all three human anti-α-synuclein antibodies across tissue treatment conditions by immunohistochemistry. Our results suggest that the memory B-cell repertoire of PD patients might represent a potential source of biomarkers and therapies.
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Affiliation(s)
- Xinyi Li
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Wouter Koudstaal
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
- Present Address: Lucidity Biomedical Consulting, Calle Emir 11, 18006 Granada, Spain
| | - Lauren Fletcher
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Martha Costa
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Margot van Winsen
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
| | - Berdien Siregar
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
| | - Hanna Inganäs
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
| | - Julie Kim
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Elissa Keogh
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Jeremy Macedo
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Trevin Holland
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Stuart Perry
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Frederique Bard
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
| | - Jeroen J. Hoozemans
- Department of Pathology, Amsterdam Neuroscience, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Jaap Goudsmit
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115 USA
- Department of Neurology, Amsterdam Neuroscience, Academic Medical Center, Meidreefberg 9, 1105 AZ Amsterdam, The Netherlands
| | - Adrian Apetri
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, Archimedesweg 6, 2333 CN Leiden, The Netherlands
| | - Gabriel Pascual
- Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 3210 Merryfield Row, San Diego, CA 92121 USA
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17
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Bray C, Wright D, Haupt S, Thomas S, Stauss H, Zamoyska R. Crispr/Cas Mediated Deletion of PTPN22 in Jurkat T Cells Enhances TCR Signaling and Production of IL-2. Front Immunol 2018; 9:2595. [PMID: 30483260 PMCID: PMC6240618 DOI: 10.3389/fimmu.2018.02595] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/22/2018] [Indexed: 01/25/2023] Open
Abstract
A single nucleotide polymorphism, C1858T, in the gene encoding the protein tyrosine phosphatase nonreceptor type 22 (PTPN22) results in one of the strongest genetic traits associated with autoimmune disease outside of the Major Histocompatibility Complex (MHC) genes. However, the consequences of this polymorphism, which introduces an arginine to tryptophan substitution at amino acid 620, for the function of PTPN22 protein is unclear and conflicting results have been obtained in human compared to mouse cells expressing this variant phosphatase. In mouse the variant appears to be a loss-of-function allele resembling a milder form of the null allele, while studies in human cells have reported it to be a gain-of-function mutation. To address whether the phosphatase has distinct functions in mouse vs. human T cells, we used CRISPR gene-editing to generate the first example of human PTPN22-KnockOut (KO) T cells. By comparing isogenic human T cells which express or lack PTPN22, we showed that PTPN22 KO T cells displayed enhanced expression of IL-2 and CD69 upon stimulation with cognate antigen. PTPN22 KO cells also showed increased Erk phosphorylation upon stimulation with weak antigen, but the difference was diminished in response to strong antigen, indicating that PTPN22 plays a more critical role in regulating weak-antigen responses. These data are in keeping with a role for PTPN22 in determining the threshold of stimulation required to activate T cells, a critical function of autoimmune pathogenesis. Our data indicate that PTPN22 has comparable functions in mouse and human T cells, and that the conflicting results in the literature regarding the impact of the point mutation are not due to differences in the activity of PTPN22 itself, but may be related to interactions with other proteins or splice variation.
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Affiliation(s)
- Cara Bray
- School of Biological Sciences, Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - David Wright
- School of Biological Sciences, Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Sonja Haupt
- School of Biological Sciences, Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Sharyn Thomas
- Institute of Immunity and Transplantation, Royal Free Hospital, University College London, London, United Kingdom
| | - Hans Stauss
- Institute of Immunity and Transplantation, Royal Free Hospital, University College London, London, United Kingdom
| | - Rose Zamoyska
- School of Biological Sciences, Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
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18
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Lautz JD, Brown EA, Williams VanSchoiack AA, Smith SEP. Synaptic activity induces input-specific rearrangements in a targeted synaptic protein interaction network. J Neurochem 2018; 146:540-559. [PMID: 29804286 PMCID: PMC6150823 DOI: 10.1111/jnc.14466] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/04/2018] [Accepted: 05/22/2018] [Indexed: 12/30/2022]
Abstract
Cells utilize dynamic, network-level rearrangements in highly interconnected protein interaction networks to transmit and integrate information from distinct signaling inputs. Despite the importance of protein interaction network dynamics, the organizational logic underlying information flow through these networks is not well understood. Previously, we developed the quantitative multiplex co-immunoprecipitation platform, which allows for the simultaneous and quantitative measurement of the amount of co-association between large numbers of proteins in shared complexes. Here, we adapt quantitative multiplex co-immunoprecipitation to define the activity-dependent dynamics of an 18-member protein interaction network in order to better understand the underlying principles governing glutamatergic signal transduction. We first establish that immunoprecipitation detected by flow cytometry can detect activity-dependent changes in two known protein-protein interactions (Homer1-mGluR5 and PSD-95-SynGAP). We next demonstrate that neuronal stimulation elicits a coordinated change in our targeted protein interaction network, characterized by the initial dissociation of Homer1 and SynGAP-containing complexes followed by increased associations among glutamate receptors and PSD-95. Finally, we show that stimulation of distinct glutamate receptor types results in different modular sets of protein interaction network rearrangements, and that cells activate both modules in order to integrate complex inputs. This analysis demonstrates that cells respond to distinct types of glutamatergic input by modulating different combinations of protein co-associations among a targeted network of proteins. Our data support a model of synaptic plasticity in which synaptic stimulation elicits dissociation of pre-existing multiprotein complexes, opening binding slots in scaffold proteins and allowing for the recruitment of additional glutamatergic receptors. Open Science: This manuscript was awarded with the Open Materials Badge. For more information see: https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Jonathan D Lautz
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Emily A Brown
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | | | - Stephen E P Smith
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
- Graduate Program in Neuroscience, University of Washington, Seattle, Washington, USA
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19
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Hiwa R, Ohmura K, Arase N, Jin H, Hirayasu K, Kohyama M, Suenaga T, Saito F, Terao C, Atsumi T, Iwatani H, Mimori T, Arase H. Myeloperoxidase/HLA Class II Complexes Recognized by Autoantibodies in Microscopic Polyangiitis. Arthritis Rheumatol 2017; 69:2069-2080. [DOI: 10.1002/art.40170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 06/01/2017] [Indexed: 02/02/2023]
Affiliation(s)
- Ryosuke Hiwa
- World Premier International Immunology Frontier Research Center and Osaka University, Suita, Japan, and Kyoto University; Kyoto Japan
| | | | | | - Hui Jin
- World Premier International Immunology Frontier Research Center and Osaka University; Suita Japan
| | - Kouyuki Hirayasu
- World Premier International Immunology Frontier Research Center; Suita Japan
| | - Masako Kohyama
- World Premier International Immunology Frontier Research Center and Osaka University; Suita Japan
| | - Tadahiro Suenaga
- World Premier International Immunology Frontier Research Center and Osaka University; Suita Japan
| | | | | | - Tatsuya Atsumi
- Hokkaido University Graduate School of Medicine; Sapporo Japan
| | | | | | - Hisashi Arase
- World Premier International Immunology Frontier Research Center and Osaka University; Suita Japan
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20
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Tanner MR, Pennington MW, Laragione T, Gulko PS, Beeton C. KCa1.1 channels regulate β 1-integrin function and cell adhesion in rheumatoid arthritis fibroblast-like synoviocytes. FASEB J 2017; 31:3309-3320. [PMID: 28428266 DOI: 10.1096/fj.201601097r] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 04/05/2017] [Indexed: 01/01/2023]
Abstract
Large-conductance calcium-activated potassium channel (KCa1.1; BK, Slo1, MaxiK, KCNMA1) is the predominant potassium channel expressed at the plasma membrane of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs) isolated from the synovium of patients with RA. It is a critical regulator of RA-FLS migration and invasion and therefore represents an attractive target for the therapy of RA. However, the molecular mechanisms by which KCa1.1 regulates RA-FLS invasiveness have remained largely unknown. Here, we demonstrate that KCa1.1 regulates RA-FLS adhesion through controlling the plasma membrane expression and activation of β1 integrins, but not α4, α5, or α6 integrins. Blocking KCa1.1 disturbs calcium homeostasis, leading to the sustained phosphorylation of Akt and the recruitment of talin to β1 integrins. Interestingly, the pore-forming α subunit of KCa1.1 coimmunoprecipitates with β1 integrins, suggesting that this physical association underlies the functional interaction between these molecules. Together, these data outline a new signaling mechanism by which KCa1.1 regulates β1-integrin function and therefore invasiveness of RA-FLSs.-Tanner, M. R., Pennington, M. W., Laragione, T., Gulko, P. S., Beeton, C. KCa1.1 channels regulate β1-integrin function and cell adhesion in rheumatoid arthritis fibroblast-like synoviocytes.
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Affiliation(s)
- Mark R Tanner
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, USA.,Graduate School of Biomedical Sciences, Baylor College of Medicine, Houston, Texas, USA
| | | | - Teresina Laragione
- Division of Rheumatology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Pércio S Gulko
- Division of Rheumatology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Christine Beeton
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, USA; .,Biology of Inflammation Center, Baylor College of Medicine, Houston, Texas, USA.,Center for Drug Discovery, Baylor College of Medicine, Houston, Texas, USA
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21
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Smith SEP, Neier SC, Reed BK, Davis TR, Sinnwell JP, Eckel-Passow JE, Sciallis GF, Wieland CN, Torgerson RR, Gil D, Neuhauser C, Schrum AG. Multiplex matrix network analysis of protein complexes in the human TCR signalosome. Sci Signal 2016; 9:rs7. [PMID: 27485017 DOI: 10.1126/scisignal.aad7279] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Multiprotein complexes transduce cellular signals through extensive interaction networks, but the ability to analyze these networks in cells from small clinical biopsies is limited. To address this, we applied an adaptable multiplex matrix system to physiologically relevant signaling protein complexes isolated from a cell line or from human patient samples. Focusing on the proximal T cell receptor (TCR) signalosome, we assessed 210 pairs of PiSCES (proteins in shared complexes detected by exposed surface epitopes). Upon stimulation of Jurkat cells with superantigen-loaded antigen-presenting cells, this system produced high-dimensional data that enabled visualization of network activity. A comprehensive analysis platform generated PiSCES biosignatures by applying unsupervised hierarchical clustering, principal component analysis, an adaptive nonparametric with empirical cutoff analysis, and weighted correlation network analysis. We generated PiSCES biosignatures from 4-mm skin punch biopsies from control patients or patients with the autoimmune skin disease alopecia areata. This analysis distinguished disease patients from the controls, detected enhanced basal TCR signaling in the autoimmune patients, and identified a potential signaling network signature that may be indicative of disease. Thus, generation of PiSCES biosignatures represents an approach that can provide information about the activity of protein signaling networks in samples including low-abundance primary cells from clinical biopsies.
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Affiliation(s)
- Stephen E P Smith
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Steven C Neier
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Brendan K Reed
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Tessa R Davis
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Jason P Sinnwell
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Jeanette E Eckel-Passow
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | | | - Diana Gil
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Claudia Neuhauser
- University of Minnesota Informatics Institute, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Adam G Schrum
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
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22
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Abstract
The onset of the AIDS pandemic in the early 1980s coincided with the convergence of technologies now collectively known as flow cytometry (FCM). Major advances in FCM led significantly toward our understanding of the pathogenicity of the disease, which in turn led to wider adoption of the technology, including using it effectively in a variety of diagnostics. CD4+ T lymphocyte population counts, along with human immunodeficiency virus (HIV) viral load, remain the gold standard in diagnosis and continue to play a major role in the monitoring of advanced retroviral therapies. Arguably, the spread of AIDS (acquired immunodeficiency syndrome), the HIV virus, and the toll of the virus on humanity have been considerably altered by the concurrent development of FCM, the details of which are presented herein.
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Affiliation(s)
- Ian C Clift
- Indiana University South Bend School of Applied Health Sciences, South Bend, IN
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23
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Glassman CR, Parrish HL, Deshpande NR, Kuhns MS. The CD4 and CD3δε Cytosolic Juxtamembrane Regions Are Proximal within a Compact TCR-CD3-pMHC-CD4 Macrocomplex. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2016; 196:4713-22. [PMID: 27183595 PMCID: PMC4875830 DOI: 10.4049/jimmunol.1502110] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 03/29/2016] [Indexed: 12/15/2022]
Abstract
TCRs relay information about peptides embedded within MHC molecules (pMHC) to the ITAMs of the associated CD3γε, CD3δε, and CD3ζζ signaling modules. CD4 then recruits the Src kinase p56(Lck) (Lck) to the TCR-CD3 complex to phosphorylate the ITAMs, initiate intracellular signaling, and drive CD4(+) T cell fate decisions. Whereas the six ITAMs of CD3ζζ are key determinants of T cell development, activation, and the execution of effector functions, multiple models predict that CD4 recruits Lck proximal to the four ITAMs of the CD3 heterodimers. We tested these models by placing FRET probes at the cytosolic juxtamembrane regions of CD4 and the CD3 subunits to evaluate their relationship upon pMHC engagement in mouse cell lines. The data are consistent with a compact assembly in which CD4 is proximal to CD3δε, CD3ζζ resides behind the TCR, and CD3γε is offset from CD3δε. These results advance our understanding of the architecture of the TCR-CD3-pMHC-CD4 macrocomplex and point to regions of high CD4-Lck + ITAM concentrations therein. The findings thus have implications for TCR signaling, as phosphorylation of the CD3 ITAMs by CD4-associated Lck is important for CD4(+) T cell fate decisions.
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Affiliation(s)
- Caleb R Glassman
- Department of Immunobiology, The University of Arizona College of Medicine, Tucson, AZ 85724
| | - Heather L Parrish
- Department of Immunobiology, The University of Arizona College of Medicine, Tucson, AZ 85724
| | - Neha R Deshpande
- Department of Immunobiology, The University of Arizona College of Medicine, Tucson, AZ 85724; The Arizona Center on Aging, The University of Arizona College of Medicine, Tucson, AZ 85724; and
| | - Michael S Kuhns
- Department of Immunobiology, The University of Arizona College of Medicine, Tucson, AZ 85724; The Arizona Center on Aging, The University of Arizona College of Medicine, Tucson, AZ 85724; and The BIO5 Institute, The University of Arizona College of Medicine, Tucson, AZ 85724
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24
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In Vitro Analysis of Thymocyte Signaling. Methods Mol Biol 2016; 1323:169-78. [PMID: 26294408 DOI: 10.1007/978-1-4939-2809-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
From the moment a developing thymocyte expresses a TCR, it is subjected to numerous interactions with self-peptide/MHC complexes that determine its ultimate fate. These include death by neglect, negative selection (apoptosis and lineage deviation), positive selection, and lineage commitment. The identification of signals that govern these unique cell fates requires the ability to assess the activity, level of expression, subcellular location, and the molecular associations of numerous proteins within the developing T cell. Thus, this chapter describes methods designed to analyze thymocyte signaling under various types of peptide-based stimulation in vitro.
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25
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Cunningham CA, Cardwell LN, Guan Y, Teixeiro E, Daniels MA. POSH Regulates CD4+ T Cell Differentiation and Survival. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2016; 196:4003-13. [PMID: 27084103 PMCID: PMC4868786 DOI: 10.4049/jimmunol.1501728] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 03/14/2016] [Indexed: 12/24/2022]
Abstract
The scaffold molecule POSH is crucial for the regulation of proliferation and effector function in CD8(+) T cells. However, its role in CD4(+) T cells is not known. In this study, we found that disruption of the POSH scaffold complex established a transcriptional profile that strongly skewed differentiation toward Th2, led to decreased survival, and had no effect on cell cycle entry. This is in stark contrast to CD8(+) T cells in which POSH regulates cell cycle and does not affect survival. Disruption of POSH in CD4(+) T cells resulted in the loss of Tak1-dependent activation of JNK1/2 and Tak1-mediated survival. However, in CD8(+) T cells, POSH regulates only JNK1. Remarkably, each type of T cell had a unique composition of the POSH scaffold complex and distinct posttranslational modifications of POSH. These data indicate that the mechanism that regulates POSH function in CD4(+) T cells is different from CD8(+) T cells. All together, these data strongly suggest that POSH is essential for the integration of cell-type-specific signals that regulate the differentiation, survival, and function of T cells.
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Affiliation(s)
- Cody A Cunningham
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Leah N Cardwell
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Yue Guan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Emma Teixeiro
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Mark A Daniels
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212
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26
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Abstract
Potentially harmful T cell precursors are removed from the conventional T cell pool by negative selection. This process can involve the induction of apoptosis, anergy, receptor editing or deviation into a regulatory T cell lineage. As such this process is essential for the health of an organism through its contribution to central and peripheral tolerance. While a great deal is known about the process, the precise mechanisms that regulate negative selection are not clear. Furthermore, the signals that distinguish the different forms of negative selection are not fully understood. Numerous models exist with the potential to address these questions in vitro and in vivo. This chapter describes methods of fetal thymic organ culture designed to analyze the signals that determine these unique cell fates.
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27
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Reed BK, Chopp LB, Malo CS, Renner DN, Van Keulen VS, Girtman MA, Nevala WN, Pavelko KD, Gil D, Schrum AG, Johnson AJ, Pease LR. A Versatile Simple Capture Assay for Assessing the Structural Integrity of MHC Multimer Reagents. PLoS One 2015; 10:e0137984. [PMID: 26389800 PMCID: PMC4577079 DOI: 10.1371/journal.pone.0137984] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 08/24/2015] [Indexed: 11/18/2022] Open
Abstract
Antigen-specific T cell responses can be visualized using MHC:peptide multimers. In cases where robust T cell controls are not readily available to assess the integrity of multimer reagents prior to analyzing limited sample, the ability to assess the structural integrity of MHC multimers before their use in critical experiments would be useful. We present a method to probe the structural integrity of MHC multimers using antibodies specific for conformational determinants. Beads coated with anti-mouse Ig are incubated with conformation-specific mouse monoclonal antibody and then with fluorescently tagged MHC multimer. The ability of the bead to capture the labeled multimer can be measured semi-quantitatively by flow cytometry. In this manner, the correct folding of MHC multimers can be visualized and batches of multimer can be compared for quality control. Because there are multiple conformational epitopes formed by various molecular interactions among heavy chain, peptide, and β2M, this capture assay can assess the fidelity of each aspect of multimer structure, depending on the availability of antibodies. The described approach could be particularly useful for studies using irreplaceable samples, including patient samples collected in clinical trials.
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Affiliation(s)
- Brendan K. Reed
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Laura B. Chopp
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Courtney S. Malo
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Danielle N. Renner
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Virginia S. Van Keulen
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Megan A. Girtman
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Wendy N. Nevala
- Department of Medicine, Division of Hematology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Kevin D. Pavelko
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Diana Gil
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Adam G. Schrum
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Aaron J. Johnson
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Larry R. Pease
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, United States of America
- * E-mail:
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28
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Ultrasensitive measurement of huntingtin protein in cerebrospinal fluid demonstrates increase with Huntington disease stage and decrease following brain huntingtin suppression. Sci Rep 2015; 5:12166. [PMID: 26174131 PMCID: PMC4502413 DOI: 10.1038/srep12166] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 06/18/2015] [Indexed: 11/26/2022] Open
Abstract
Quantitation of huntingtin protein in the brain is needed, both as a marker of Huntington disease (HD) progression and for use in clinical gene silencing trials. Measurement of huntingtin in cerebrospinal fluid could be a biomarker of brain huntingtin, but traditional protein quantitation methods have failed to detect huntingtin in cerebrospinal fluid. Using micro-bead based immunoprecipitation and flow cytometry (IP-FCM), we have developed a highly sensitive mutant huntingtin detection assay. The sensitivity of huntingtin IP-FCM enables accurate detection of mutant huntingtin protein in the cerebrospinal fluid of HD patients and model mice, demonstrating that mutant huntingtin levels in cerebrospinal fluid reflect brain levels, increasing with disease stage and decreasing following brain huntingtin suppression. This technique has potential applications as a research tool and as a clinical biomarker.
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29
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Smith SEP, Neier SC, Davis TR, Pittelkow MR, Gil D, Schrum AG. Signalling protein complexes isolated from primary human skin-resident T cells can be analysed by Multiplex IP-FCM. Exp Dermatol 2015; 23:272-3. [PMID: 24588717 DOI: 10.1111/exd.12362] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2014] [Indexed: 11/29/2022]
Abstract
Studying signal transduction in skin-resident T cells (sr-T cells) can be limited by the small size of clinical biopsies. Here, we isolated sr-T cells from clinical samples and analysed signalling protein complexes by multiplex immunoprecipitation detected by flow cytometry (mIP-FCM). In samples from two independent donors, antigenic stimulation induced signalling proteins to join shared complexes that were observed in seven pairwise combinations among five proteins. This demonstrates that sr-T cells isolated from small clinical samples provide sufficient material for mIP-FCM-based analysis of signalling-induced protein complexes. We propose that this strategy may be useful for gaining improved mechanistic insight of sr-T cell signal transduction associated with dermatological disease.
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Affiliation(s)
- Stephen E P Smith
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
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30
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Stepanek O, Prabhakar AS, Osswald C, King CG, Bulek A, Naeher D, Beaufils-Hugot M, Abanto ML, Galati V, Hausmann B, Lang R, Cole DK, Huseby ES, Sewell AK, Chakraborty AK, Palmer E. Coreceptor scanning by the T cell receptor provides a mechanism for T cell tolerance. Cell 2014; 159:333-45. [PMID: 25284152 PMCID: PMC4304671 DOI: 10.1016/j.cell.2014.08.042] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 07/14/2014] [Accepted: 08/29/2014] [Indexed: 12/11/2022]
Abstract
In the thymus, high-affinity, self-reactive thymocytes are eliminated from the pool of developing T cells, generating central tolerance. Here, we investigate how developing T cells measure self-antigen affinity. We show that very few CD4 or CD8 coreceptor molecules are coupled with the signal-initiating kinase, Lck. To initiate signaling, an antigen-engaged T cell receptor (TCR) scans multiple coreceptor molecules to find one that is coupled to Lck; this is the first and rate-limiting step in a kinetic proofreading chain of events that eventually leads to TCR triggering and negative selection. MHCII-restricted TCRs require a shorter antigen dwell time (0.2 s) to initiate negative selection compared to MHCI-restricted TCRs (0.9 s) because more CD4 coreceptors are Lck-loaded compared to CD8. We generated a model (Lck come&stay/signal duration) that accurately predicts the observed differences in antigen dwell-time thresholds used by MHCI- and MHCII-restricted thymocytes to initiate negative selection and generate self-tolerance.
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Affiliation(s)
- Ondrej Stepanek
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland.
| | - Arvind S Prabhakar
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Celine Osswald
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Carolyn G King
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Anna Bulek
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, UK
| | - Dieter Naeher
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Marina Beaufils-Hugot
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Michael L Abanto
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Virginie Galati
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Barbara Hausmann
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - Rosemarie Lang
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland
| | - David K Cole
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, UK
| | - Eric S Huseby
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Andrew K Sewell
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, UK
| | - Arup K Chakraborty
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Institute for Medical Engineering and Science, Departments of Physics, Chemistry, and Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Ragon Institute of MGH, MIT, and Harvard, 400 Technology Square, Cambridge, MA 02139, USA
| | - Ed Palmer
- Departments of Biomedicine and Nephrology, University Hospital Basel and University of Basel, 4031 Basel, Switzerland.
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31
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Baumgart F, Schütz GJ. Detecting protein association at the T cell plasma membrane. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:791-801. [PMID: 25300585 DOI: 10.1016/j.bbamcr.2014.09.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/18/2014] [Accepted: 09/29/2014] [Indexed: 10/24/2022]
Abstract
At the moment, many models on T cell signaling rely on results obtained via rather indirect methodologies, which makes direct comparison and conclusions to the in vivo situation difficult. Recently, a variety of new imaging methods were developed, which have the potential to directly shed light onto the mysteries of protein association at the T cell membrane. While the new modalities are extremely promising, for a broad readership it may be difficult to judge the results, since technological shortcomings are not always obvious. In this review article, we put key questions on the mechanism of protein interactions in the T cell plasma membrane into relation with techniques that allow to address such questions. We discuss applicability of the techniques, their strengths and weaknesses. This article is part of a Special Issue entitled: Nanoscale membrane organisation and signalling.
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Affiliation(s)
- Florian Baumgart
- Vienna University of Technology, Institute for Applied Physics, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - Gerhard J Schütz
- Vienna University of Technology, Institute for Applied Physics, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria.
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32
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Borroto A, Arellano I, Blanco R, Fuentes M, Orfao A, Dopfer EP, Prouza M, Suchànek M, Schamel WW, Alarcón B. Relevance of Nck-CD3 epsilon interaction for T cell activation in vivo. THE JOURNAL OF IMMUNOLOGY 2014; 192:2042-53. [PMID: 24470497 DOI: 10.4049/jimmunol.1203414] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
On TCR ligation, the adaptor Nck is recruited through its src homology 3.1 domain to a proline-rich sequence (PRS) in CD3ε. We have studied the relevance of this interaction for T cell activation in vitro and in vivo by targeting the interaction sites in both partners. The first approach consisted of studying a knockin (KI) mouse line (KI-PRS) bearing a conservative mutation in the PRS that makes the TCR incompetent to recruit Nck. This deficiency prevents T cell activation by Ag in vitro and inhibited very early TCR signaling events including the tyrosine phosphorylation of CD3ζ. Most important, KI-PRS mice are partly protected against the development of neurological symptoms in an experimental autoimmune encephalitis model, and show a deficient antitumoral response after vaccination. The second approach consisted of using a high-affinity peptide that specifically binds the src homology 3.1 domain and prevents the interaction of Nck with CD3ε. This peptide inhibits T cell proliferation in vitro and in vivo. These data suggest that Nck recruitment to the TCR is fundamental to mount an efficient T cell response in vivo, and that the Nck-CD3ε interaction may represent a target for pharmacological modulation of the immune response.
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Affiliation(s)
- Aldo Borroto
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
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33
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Neier SC, Smith SEP, Davis TR, Gil D, Schrum AG. Toward T cell protein-protein interaction activity relevant to alopecia areata. J Investig Dermatol Symp Proc 2013; 16:S31-3. [PMID: 24326546 DOI: 10.1038/jidsymp.2013.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Development of better therapies for the T cell-mediated autoimmune disease alopecia areata (AA) could be expedited by an improved understanding of the immunologic signals underlying its pathogenesis. To approach this, our group is mounting a new technological and analytical platform, multiplex immunoprecipitation detected by flow cytometry (MIF). MIF is designed to allow analysis of collections of protein-protein interactions that participate in T cell signaling webs. Early experiments suggest that MIF can detect the increased protein-protein interaction network activity that occurs under conditions of T cell antigenic stimulation. Future experiments will focus on application of MIF to T cells isolated from AA or control patient samples, to identify critical T cell signaling complexes associated with the disorder.
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Affiliation(s)
- Steven C Neier
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, Minnesota, USA
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34
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Cao FF, Xu LM, Zhang X, Wang Y, Li MQ, Uzan G, Peng B, Zhang DH. IP-FCM platform detects the existence and regulator-caused dissociation of components in naturally assembled HSP90 complex. Cytometry A 2013; 85:359-67. [PMID: 24265268 DOI: 10.1002/cyto.a.22421] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 10/28/2013] [Accepted: 11/06/2013] [Indexed: 11/09/2022]
Abstract
Flow cytometry, in conjunction with immunoprecipitation (IP-FCM), is suggested to have some advantages to conventional IP-western blot technology in analyzing protein complexes. In this paper, to further examine its practicability, we test the use of IP-FCM in detecting the HSP90 complex, which has gained importance in drug research and development and involves more than a dozen components. We found that IP-FCM could effectively detect HSP70, p23, Cdc37, and Cdk6 components in the HSP90 complex naturally formed in U937 cells when this complex was captured by anti-HSP90 antibody-coated polystyrene microspheres. IP-FCM could also detect alteration in components caused by treating cells with HSP90 inhibitors. In a cell-free environment, IP-FCM could detect the direct effects of ATP and/or HSP90 inhibitors (17-N-allylamino-17-demethoxygeldanamycin or celastrol) in causing component dissociation and the time- and dose-effects of inhibitor-caused dissociation. IP-FCM is a practical and powerful platform for analyzing HSP90 complex components, and is thus a useful tool in studying HSP90 complex function and screening inhibitors.
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Affiliation(s)
- Fan-Fan Cao
- Sino-French Cooperative Central Lab, Shanghai Gongli Hospital, Pudong New District, Shanghai, People's Republic of China
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35
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Deswal S, Meyer A, Fiala GJ, Eisenhardt AE, Schmitt LC, Salek M, Brummer T, Acuto O, Schamel WWA. Kidins220/ARMS Associates with B-Raf and the TCR, Promoting Sustained Erk Signaling in T Cells. THE JOURNAL OF IMMUNOLOGY 2013; 190:1927-35. [DOI: 10.4049/jimmunol.1200653] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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36
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Schrum AG, Gil D. Robustness and Specificity in Signal Transduction via Physiologic Protein Interaction Networks. CLINICAL & EXPERIMENTAL PHARMACOLOGY 2012; 2:S3.001. [PMID: 24535485 PMCID: PMC3923534 DOI: 10.4172/2161-1459.s3-001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The collective Protein:Protein Interactions (PPI) of a cell are thought to represent a system with emergent network properties that integrate signals from a multiplicity of inputs into coordinated responses. It is hypothesized that the PPI network supplies both specificity for many distinct signals that utilize common intermediate pathways, and also robustness by allowing specific signals to be communicated by alternate routes. Progress with genetic networks points to these concepts, but the extent to which PPI networks possess these properties has not been empirically tested, due to lack of quantitative data needed for such assessments. Here, a hypothetical physiologic PPI network is used to illustrate how signaling robustness and specificity could be manifest under conditions of (i) deletion mutation, or (ii) changes in signaling due to variation in environmental conditions or stimuli. It is proposed that advances in technology enabling empirical analysis of PPI network principles will have the potential to significantly impact basic understanding of signaling mechanisms, and contribute to the generation of novel applications in drug screening and pharmacology.
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Affiliation(s)
- Adam G. Schrum
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Diana Gil
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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Murphy PJM, Franklin HR, Furukawa NW. Biochemical reconstitution of steroid receptor•Hsp90 protein complexes and reactivation of ligand binding. J Vis Exp 2011:3059. [PMID: 21968922 DOI: 10.3791/3059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Hsp90 is an essential and highly abundant molecular chaperone protein that has been found to regulate more than 150 eukaryotic signaling proteins, including transcription factors (e.g. nuclear receptors, p53) and protein kinases (e.g. Src, Raf, Akt kinase) involved in cell cycling, tumorigenesis, apoptosis, and multiple eukaryotic signaling pathways (1,2). Of these many 'client' proteins for hsp90, the assembly of steroid receptor•hsp90 complexes is the best defined (Figure 1). We present here an adaptable glucocorticoid receptor (GR) immunoprecipitation assay and in vitro GR•hsp90 reconstitution method that may be readily used to probe eukaryotic hsp90 functional activity, hsp90-mediated steroid receptor ligand binding, and molecular chaperone cofactor requirements. For example, this assay can be used to test hsp90 cofactor requirements and the effects of adding exogenous compounds to the reconstitution process. The GR has been a particularly useful system for studying hsp90 because the receptor must be bound to hsp90 to have an open ligand binding cleft that is accessible to steroid (3). Endogenous, unliganded GR is present in the cytoplasm of mammalian cells noncovalently bound to hsp90. As found in the endogenous GR•hsp90 heterocomplex, the GR ligand binding cleft is open and capable of binding steroid. If hsp90 dissociates from the GR or if its function is inhibited, the receptor is unable to bind steroid and requires reconstitution of the GR•hsp90 heterocomplex before steroid binding activity is restored (4) . GR can be immunoprecipitated from cell cytosol using a monoclonal antibody, and proteins such as hsp90 complexed to the GR can be assayed by western blot. Steroid binding activity of the immunoprecipitated GR can be determined by incubating the immunopellet with [(3)H]steroid. Previous experiments have shown hsp90-mediated opening of the GR ligand binding cleft requires hsp70, a second molecular chaperone also essential for eukaryotic cell viability. Biochemical activity of hsp90 and hsp70 are catalyzed by co-chaperone proteins Hop, hsp40, and p23 (5). A multiprotein chaperone machinery containing hsp90, hsp70, Hop, and hsp40 are endogenously present in eukaryotic cell cytoplasm, and reticulocyte lysate provides a chaperone-rich protein source (6). In the method presented, GR is immunoadsorbed from cell cytosol and stripped of the endogenous hsp90/hsp70 chaperone machinery using mild salt conditions. The salt-stripped GR is then incubated with reticulocyte lysate, ATP, and K(+), which results in the reconstitution of the GR•hsp90 heterocomplex and reactivation of steroid binding activity (7). This method can be utilized to test the effects of various chaperone cofactors, novel proteins, and experimental hsp90 or GR inhibitors in order to determine their functional significance on hsp90-mediated steroid binding (8-11).
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Affiliation(s)
- Patrick J M Murphy
- College of Nursing, Interdisciplinary Life Sciences Research Laboratory, Seattle University, WA, USA
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Bida AT, Gil D, Schrum AG. Multiplex IP-FCM (immunoprecipitation-flow cytometry): Principles and guidelines for assessing physiologic protein-protein interactions in multiprotein complexes. Methods 2011; 56:154-60. [PMID: 21945581 DOI: 10.1016/j.ymeth.2011.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 09/05/2011] [Accepted: 09/09/2011] [Indexed: 12/13/2022] Open
Abstract
There is significant interest in the development of methods with the potential to increase access to 'the interactome' for both experimental and clinical applications. Immunoprecipitation detected by flow cytometry (IP-FCM) is a robust, biochemical method that can be used for measuring physiologic protein-protein interactions (PPI) in multiprotein complexes (MPC) with high sensitivity. Because it is based on antibody-mediated capture of protein complexes onto microspheres, IP-FCM is potentially compatible with a multiplex platform that could allow simultaneous assessment of many physiologic PPI. Here, we consider the principles of ambient analyte conditions (AAC) and inter-bead independence, and provide a template set of experiments showing how to convert singleplex IP-FCM to multiplex IP-FCM, including assays to confirm the validity of the experimental conditions for data acquisition. We conclude that singleplex IP-FCM can be successfully upgraded to multiplex format, and propose that the unique strengths of multiplex IP-FCM make it a method that is likely to facilitate the acquisition of new PPI data from primary cell sources.
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Affiliation(s)
- Anya T Bida
- Mayo Clinic College of Medicine, Department of Immunology, Rochester, MN, USA
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Deswal S, Schulze AK, Höfer T, Schamel WWA. Quantitative analysis of protein phosphorylations and interactions by multi-colour IP-FCM as an input for kinetic modelling of signalling networks. PLoS One 2011; 6:e22928. [PMID: 21829558 PMCID: PMC3146539 DOI: 10.1371/journal.pone.0022928] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 07/01/2011] [Indexed: 11/22/2022] Open
Abstract
Background To understand complex biological signalling mechanisms, mathematical modelling of signal transduction pathways has been applied successfully in last few years. However, precise quantitative measurements of signal transduction events such as activation-dependent phosphorylation of proteins, remains one bottleneck to this success. Methodology/Principal Findings We use multi-colour immunoprecipitation measured by flow cytometry (IP-FCM) for studying signal transduction events to unrivalled precision. In this method, antibody-coupled latex beads capture the protein of interest from cellular lysates and are then stained with differently fluorescent-labelled antibodies to quantify the amount of the immunoprecipitated protein, of an interaction partner and of phosphorylation sites. The fluorescence signals are measured by FCM. Combining this procedure with beads containing defined amounts of a fluorophore allows retrieving absolute numbers of stained proteins, and not only relative values. Using IP-FCM we derived multidimensional data on the membrane-proximal T-cell antigen receptor (TCR-CD3) signalling network, including the recruitment of the kinase ZAP70 to the TCR-CD3 and subsequent ZAP70 activation by phosphorylation in the murine T-cell hybridoma and primary murine T cells. Counter-intuitively, these data showed that cell stimulation by pervanadate led to a transient decrease of the phospho-ZAP70/ZAP70 ratio at the TCR. A mechanistic mathematical model of the underlying processes demonstrated that an initial massive recruitment of non-phosphorylated ZAP70 was responsible for this behaviour. Further, the model predicted a temporal order of multisite phosphorylation of ZAP70 (with Y319 phosphorylation preceding phosphorylation at Y493) that we subsequently verified experimentally. Conclusions/Significance The quantitative data sets generated by IP-FCM are one order of magnitude more precise than Western blot data. This accuracy allowed us to gain unequalled insight into the dynamics of the TCR-CD3-ZAP70 signalling network.
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Affiliation(s)
- Sumit Deswal
- Max Planck Institute of Immunobiology and Epigenetics, and Faculty of Biology, Biology III, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine, Freiburg, Germany
| | - Anna K. Schulze
- Research Group Modeling of Biological Systems, German Cancer Research Center and BioQuant Center, Heidelberg, Germany
| | - Thomas Höfer
- Research Group Modeling of Biological Systems, German Cancer Research Center and BioQuant Center, Heidelberg, Germany
| | - Wolfgang W. A. Schamel
- Max Planck Institute of Immunobiology and Epigenetics, and Faculty of Biology, Biology III, University of Freiburg, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Centre of Chronic Immunodeficiency (CCI), University Medical Center Freiburg, and University of Freiburg, Freiburg, Germany
- * E-mail:
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Schrum AG, Gil D, Turka LA, Palmer E. Physical and functional bivalency observed among TCR/CD3 complexes isolated from primary T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 187:870-8. [PMID: 21666056 PMCID: PMC3131427 DOI: 10.4049/jimmunol.1100538] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Unlike BCR and secreted Ig, TCR expression is not thought to occur in a bivalent form. The conventional monovalent model of TCR/CD3 is supported by published studies of complexes solubilized in the detergent digitonin, in which bivalency was not observed. We revisited the issue of TCR valency by examining complexes isolated from primary αβ T cells after solubilization in digitonin. Using immunoprecipitation followed by flow cytometry, we unexpectedly observed TCR/CD3 complexes that contained two TCRs per complex. Standard anti-TCR Abs, being bivalent themselves, tended to bind with double occupancy to bivalent TCRs; this property masked the presence of the second TCR per complex in certain Ab binding assays, which may partially explain why previous data did not reveal these bivalent complexes. We also found that the prevalence of bivalency among fully assembled, mature TCR/CD3 complexes was sufficient to impact the functional performance of immunoprecipitated TCRs in binding antigenic peptide/MHC-Ig fusion proteins. Both TCR positions per bivalent complex required an Ag-specific TCR to effect optimal binding to these soluble ligands. Therefore, we conclude that in primary T cells, TCR/CD3 complexes can be found that are physically and functionally bivalent. The expression of bivalent TCR/CD3 complexes has implications regarding potential mechanisms by which Ag may trigger signaling. It also suggests the possibility that the potential for bivalent expression could represent a general feature of Ag receptors.
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MESH Headings
- Adaptive Immunity/genetics
- Animals
- CD3 Complex/genetics
- CD3 Complex/isolation & purification
- CD3 Complex/physiology
- Flow Cytometry
- Immunoprecipitation
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Protein Multimerization/genetics
- Protein Multimerization/immunology
- Receptor-CD3 Complex, Antigen, T-Cell/genetics
- Receptor-CD3 Complex, Antigen, T-Cell/isolation & purification
- Receptor-CD3 Complex, Antigen, T-Cell/physiology
- T-Lymphocyte Subsets/chemistry
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
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Affiliation(s)
- Adam G. Schrum
- Department of Immunology, 200 First Street SW, Mayo Clinic College of Medicine, Rochester MN, 55905, USA
- Department of Medicine, 415 Curie Blvd, University of Pennsylvania School of Medicine, Philadelphia PA, 19104, USA
- Laboratory of Transplantation Immunology and Nephrology, Department of Research, University Hospital-Basel, Hebelstrasse 20, 4031-Basel, Switzerland
| | - Diana Gil
- Department of Immunology, 200 First Street SW, Mayo Clinic College of Medicine, Rochester MN, 55905, USA
- Inmunología, Departamento de Microbiología I, Facultad de Medicina,Universidad Complutense de Madrid, Madrid 28043, Spain
| | - Laurence A. Turka
- Department of Medicine, 415 Curie Blvd, University of Pennsylvania School of Medicine, Philadelphia PA, 19104, USA
| | - Ed Palmer
- Laboratory of Transplantation Immunology and Nephrology, Department of Research, University Hospital-Basel, Hebelstrasse 20, 4031-Basel, Switzerland
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de la Cruz J, Kruger T, Parks CA, Silge RL, van Oers NSC, Luescher IF, Schrum AG, Gil D. Basal and antigen-induced exposure of the proline-rich sequence in CD3ε. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:2282-90. [PMID: 21228347 PMCID: PMC3810001 DOI: 10.4049/jimmunol.1003225] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The CD3ε cytoplasmic tail contains a conserved proline-rich sequence (PRS) that influences TCR-CD3 expression and signaling. Although the PRS can bind the SH3.1 domain of the cytosolic adapter Nck, whether the PRS is constitutively available for Nck binding or instead represents a cryptic motif that is exposed via conformational change upon TCR-CD3 engagement (CD3Δc) is currently unresolved. Furthermore, the extent to which a cis-acting CD3ε basic amino acid-rich stretch (BRS), with its unique phosphoinositide-binding capability, might impact PRS accessibility is not clear. In this study, we found that freshly harvested primary thymocytes expressed low to moderate basal levels of Nck-accessible PRS ("open-CD3"), although most TCR-CD3 complexes were inaccessible to Nck ("closed-CD3"). Ag presentation in vivo induced open-CD3, accounting for half of the basal level found in thymocytes from MHC(+) mice. Additional stimulation with either anti-CD3 Abs or peptide-MHC ligands further elevated open-CD3 above basal levels, consistent with a model wherein antigenic engagement induces maximum PRS exposure. We also found that the open-CD3 conformation induced by APCs outlasted the time of ligand occupancy, marking receptors that had been engaged. Finally, CD3ε BRS-phosphoinositide interactions played no role in either adoption of the initial closed-CD3 conformation or induction of open-CD3 by Ab stimulation. Thus, a basal level of open-CD3 is succeeded by a higher, induced level upon TCR-CD3 engagement, involving CD3Δc and prolonged accessibility of the CD3ε PRS to Nck.
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MESH Headings
- Amino Acid Motifs/immunology
- Animals
- Antigen-Presenting Cells/immunology
- Antigen-Presenting Cells/metabolism
- CD3 Complex/genetics
- CD3 Complex/immunology
- CD3 Complex/metabolism
- Cell Line, Tumor
- Epitopes, T-Lymphocyte/physiology
- Hybridomas
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Proline/immunology
- Proline/metabolism
- Receptor-CD3 Complex, Antigen, T-Cell/genetics
- Receptor-CD3 Complex, Antigen, T-Cell/immunology
- Receptor-CD3 Complex, Antigen, T-Cell/metabolism
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- Javier de la Cruz
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905
- Initiative to Maximize Student Diversity and Post Baccalaureate Research Education Program, College of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Travis Kruger
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905
- Summer Undergraduate Research Fellowship Program, College of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Christopher A. Parks
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905
- Summer Undergraduate Research Fellowship Program, College of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Robert L. Silge
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Nicolai S. C. van Oers
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Immanuel F. Luescher
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, 1066 Epalinges, Switzerland
| | - Adam G. Schrum
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Diana Gil
- Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905
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Abstract
Immunoprecipitation detected by flow cytometry (IP-FCM) is an efficient method for detecting and quantifying protein-protein interactions. The basic principle extends that of sandwich ELISA, wherein the captured primary analyte can be detected together with other molecules physically associated within multiprotein complexes. The procedure involves covalent coupling of polystyrene latex microbeads with immunoprecipitating monoclonal antibodies (mAb) specific for a protein of interest, incubating these beads with cell lysates, probing captured protein complexes with fluorochrome-conjugated probes, and analyzing bead-associated fluorescence by flow cytometry. IP-FCM is extremely sensitive, allows analysis of proteins in their native (non-denatured) state, and is amenable to either semi-quantitative or quantitative analysis. As additional advantages, IP-FCM requires no genetic engineering or specialized equipment, other than a flow cytometer, and it can be readily adapted for high-throughput applications.
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Affiliation(s)
- Tessa R Davis
- Department of Immunology, College of Medicine, Mayo Clinic, USA
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Mirza N, Duque MA, Dominguez AL, Schrum AG, Dong H, Lustgarten J. B7-H1 expression on old CD8+ T cells negatively regulates the activation of immune responses in aged animals. THE JOURNAL OF IMMUNOLOGY 2010; 184:5466-5474. [PMID: 20375308 DOI: 10.4049/jimmunol.0903561] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
T cell responses are compromised in the elderly. The B7-CD28 family receptors are critical in the regulation of immune responses. We evaluated whether the B7-family and CD28-family receptors were differentially expressed in dendritic cells, macrophages, and CD4(+) and CD8(+) T cells from young and old mice, which could contribute to the immune dysfunction in the old. Although most of the receptors were equally expressed in all cells, >85% of the old naive CD8(+) T cells expressed B7-H1 compared with 25% in the young. Considering that B7-H1 negatively regulates immune responses, we hypothesized that expression of B7-H1 would downregulate the function of old CD8(+) T cells. Old CD8(+) T cells showed reduced ability to proliferate, but blockade of B7-H1 restored the proliferative capacity of old CD8(+) T cells to a level similar to young CD8(+) T cells. In vivo blockade of B7-H1 restored antitumor responses against the B7-H1(-) BM-185-enhanced GFP tumor, such that old animals responded with the same efficiency as young mice. Our data also indicate that old CD8(+) T cells express lower levels of TCR compared with young CD8(+) T cells. However, following antigenic stimulation in the presence of B7-H1 blockade, the levels of TCR expression were restored in old CD8(+) T cells, which correlated with stronger T cell activation. These studies demonstrated that expression of B7-H1 in old CD8(+) T cells impairs the proper activation of these cells and that blockade of B7-H1 could be critical to optimally stimulate a CD8 T cell response in the old.
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Affiliation(s)
- Noweeda Mirza
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ 85259
| | - Maria Adelaida Duque
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ 85259
| | - Ana Lucia Dominguez
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ 85259
| | - Adam G Schrum
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Rochester, Rochester, MN 55905
| | - Haidong Dong
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Rochester, Rochester, MN 55905
| | - Joseph Lustgarten
- Department of Immunology, Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ 85259
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Nagaraj S, Schrum AG, Cho HI, Celis E, Gabrilovich DI. Mechanism of T cell tolerance induced by myeloid-derived suppressor cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2010. [PMID: 20142361 DOI: 10.4049/jimmunol.0902661.mechanism] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Ag-specific T cell tolerance plays a critical role in tumor escape. Recent studies implicated myeloid-derived suppressor cells (MDSCs) in the induction of CD8(+) T cell tolerance in tumor-bearing hosts. However, the mechanism of this phenomenon remained unclear. We have found that incubation of Ag-specific CD8(+) T cells, with peptide-loaded MDSCs, did not induce signaling downstream of TCR. However, it prevented subsequent signaling from peptide-loaded dendritic cells. Using double TCR transgenic CD8(+) T cells, we have demonstrated that MDSC induced tolerance to only the peptide, which was presented by MDSCs. T cell response to the peptide specific to the other TCR was not affected. Incubation of MDSCs with Ag-specific CD8(+) T cells caused nitration of the molecules on the surface of CD8(+) T cells, localized to the site of physical interaction between MDSC and T cells, which involves preferentially only TCR specific for the peptide presented by MDSCs. Postincubation with MDSCs, only nitrotyrosine-positive CD8(+) T cells demonstrated profound nonresponsiveness to the specific peptide, whereas nitrotyrosine-negative CD8(+) T cells responded normally to that stimulation. MDSCs caused dissociation between TCR and CD3zeta molecules, disrupting TCR complexes on T cells. Thus, these data describe a novel mechanism of Ag-specific CD8(+) T cell tolerance in cancer.
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MESH Headings
- Adoptive Transfer
- Animals
- Antigen Presentation/genetics
- Antigen Presentation/immunology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- CD8-Positive T-Lymphocytes/transplantation
- Cell Line, Tumor
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Female
- Genes, T-Cell Receptor beta/immunology
- Leukemia, Experimental/genetics
- Leukemia, Experimental/immunology
- Leukemia, Experimental/pathology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Transgenic
- Myeloid Cells/immunology
- Myeloid Cells/pathology
- Myeloid Cells/transplantation
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/pathology
- Signal Transduction/genetics
- Signal Transduction/immunology
- Transplantation Tolerance/genetics
- Transplantation Tolerance/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- Srinivas Nagaraj
- Department of Immunology, H Lee Moffitt Cancer Center, University of South Florida, Tampa, FL 33612, USA
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Nagaraj S, Schrum AG, Cho HI, Celis E, Gabrilovich DI. Mechanism of T cell tolerance induced by myeloid-derived suppressor cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2010; 184:3106-16. [PMID: 20142361 PMCID: PMC2832724 DOI: 10.4049/jimmunol.0902661] [Citation(s) in RCA: 324] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Ag-specific T cell tolerance plays a critical role in tumor escape. Recent studies implicated myeloid-derived suppressor cells (MDSCs) in the induction of CD8(+) T cell tolerance in tumor-bearing hosts. However, the mechanism of this phenomenon remained unclear. We have found that incubation of Ag-specific CD8(+) T cells, with peptide-loaded MDSCs, did not induce signaling downstream of TCR. However, it prevented subsequent signaling from peptide-loaded dendritic cells. Using double TCR transgenic CD8(+) T cells, we have demonstrated that MDSC induced tolerance to only the peptide, which was presented by MDSCs. T cell response to the peptide specific to the other TCR was not affected. Incubation of MDSCs with Ag-specific CD8(+) T cells caused nitration of the molecules on the surface of CD8(+) T cells, localized to the site of physical interaction between MDSC and T cells, which involves preferentially only TCR specific for the peptide presented by MDSCs. Postincubation with MDSCs, only nitrotyrosine-positive CD8(+) T cells demonstrated profound nonresponsiveness to the specific peptide, whereas nitrotyrosine-negative CD8(+) T cells responded normally to that stimulation. MDSCs caused dissociation between TCR and CD3zeta molecules, disrupting TCR complexes on T cells. Thus, these data describe a novel mechanism of Ag-specific CD8(+) T cell tolerance in cancer.
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MESH Headings
- Adoptive Transfer
- Animals
- Antigen Presentation/genetics
- Antigen Presentation/immunology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- CD8-Positive T-Lymphocytes/transplantation
- Cell Line, Tumor
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Female
- Genes, T-Cell Receptor beta/immunology
- Leukemia, Experimental/genetics
- Leukemia, Experimental/immunology
- Leukemia, Experimental/pathology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Transgenic
- Myeloid Cells/immunology
- Myeloid Cells/pathology
- Myeloid Cells/transplantation
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/pathology
- Signal Transduction/genetics
- Signal Transduction/immunology
- Transplantation Tolerance/genetics
- Transplantation Tolerance/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- Srinivas Nagaraj
- Department of Immunology, H Lee Moffitt Cancer Center, University of South Florida, Tampa, FL 33612, USA
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