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Degirmencay A, Thomas S, Holler A, Burgess S, Morris EC, Stauss HJ. Exploitation of CD3ζ to enhance TCR expression levels and antigen-specific T cell function. Front Immunol 2024; 15:1386132. [PMID: 38873603 PMCID: PMC11169823 DOI: 10.3389/fimmu.2024.1386132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 05/16/2024] [Indexed: 06/15/2024] Open
Abstract
The expression levels of TCRs on the surface of human T cells define the avidity of TCR-HLA/peptide interactions. In this study, we have explored which components of the TCR-CD3 complex are involved in determining the surface expression levels of TCRs in primary human T cells. The results show that there is a surplus of endogenous TCR α/β chains that can be mobilised by providing T cells with additional CD3γ,δ,ε,ζ chains, which leads to a 5-fold increase in TCR α/β surface expression. The analysis of individual CD3 chains revealed that provision of additional ζ chain alone was sufficient to achieve a 3-fold increase in endogenous TCR expression. Similarly, CD3ζ also limits the expression levels of exogenous TCRs transduced into primary human T cells. Interestingly, transduction with TCR plus CD3ζ not only increased surface expression of the introduced TCR, but it also reduced mispairing with endogenous TCR chains, resulting in improved antigen-specific function. TCR reconstitution experiments in HEK293T cells that do not express endogenous TCR or CD3 showed that TCRα/β and all four CD3 chains were required for optimal surface expression, while in the absence of CD3ζ the TCR expression was reduced by 50%. Together, the data show that CD3ζ is a key regulator of TCR expression levels in human T cells, and that gene transfer of exogenous TCR plus CD3ζ improved TCR surface expression, reduced TCR mispairing and increased antigen-specific function.
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MESH Headings
- Humans
- CD3 Complex/immunology
- CD3 Complex/metabolism
- CD3 Complex/genetics
- HEK293 Cells
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Lymphocyte Activation/immunology
- Receptor-CD3 Complex, Antigen, T-Cell/immunology
- Receptor-CD3 Complex, Antigen, T-Cell/metabolism
- Receptor-CD3 Complex, Antigen, T-Cell/genetics
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Affiliation(s)
| | | | | | | | | | - Hans J. Stauss
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, Pears Building, London, United Kingdom
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2
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Clutton GT, Weideman AMK, Mischell MA, Kallon S, Conrad SZ, Shaw FR, Warren JA, Lin L, Kuruc JD, Xu Y, Gay CM, Armistead PM, G. Hudgens M, Goonetilleke NP. CD3 downregulation identifies high-avidity human CD8 T cells. Clin Exp Immunol 2024; 215:279-290. [PMID: 37950348 PMCID: PMC10876116 DOI: 10.1093/cei/uxad124] [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: 06/27/2023] [Revised: 09/22/2023] [Accepted: 11/07/2023] [Indexed: 11/12/2023] Open
Abstract
CD8 T cells recognize infected and cancerous cells via their T-cell receptor (TCR), which binds peptide-MHC complexes on the target cell. The affinity of the interaction between the TCR and peptide-MHC contributes to the antigen sensitivity, or functional avidity, of the CD8 T cell. In response to peptide-MHC stimulation, the TCR-CD3 complex and CD8 co-receptor are downmodulated. We quantified CD3 and CD8 downmodulation following stimulation of human CD8 T cells with CMV, EBV, and HIV peptides spanning eight MHC restrictions, observing a strong correlation between the levels of CD3 and CD8 downmodulation and functional avidity, regardless of peptide viral origin. In TCR-transduced T cells targeting a tumor-associated antigen, changes in TCR-peptide affinity were sufficient to modify CD3 and CD8 downmodulation. Correlation analysis and generalized linear modeling indicated that CD3 downmodulation was the stronger correlate of avidity. CD3 downmodulation, simply measured using flow cytometry, can be used to identify high-avidity CD8 T cells in a clinical context.
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Affiliation(s)
- Genevieve T Clutton
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ann Marie K Weideman
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Melissa A Mischell
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sallay Kallon
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Shayla Z Conrad
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Fiona R Shaw
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Joanna A Warren
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lin Lin
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - JoAnn D Kuruc
- Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Yinyan Xu
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Cynthia M Gay
- Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Paul M Armistead
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michael G. Hudgens
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nilu P Goonetilleke
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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3
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Grailer J, Cheng ZJ, Hartnett J, Slater M, Fan F, Cong M. A Novel Cell-based Luciferase Reporter Platform for the Development and Characterization of T-Cell Redirecting Therapies and Vaccine Development. J Immunother 2023; 46:96-106. [PMID: 36809225 PMCID: PMC9988225 DOI: 10.1097/cji.0000000000000453] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/23/2023] [Indexed: 02/23/2023]
Abstract
T-cell immunotherapies are promising strategies to generate T-cell responses towards tumor-derived or pathogen-derived antigens. Adoptive transfer of T cells genetically modified to express antigen receptor transgenes has shown promise for the treatment of cancer. However, the development of T-cell redirecting therapies relies on the use of primary immune cells and is hampered by the lack of easy-to-use model systems and sensitive readouts to facilitate candidate screening and development. Particularly, testing T-cell receptor (TCR)-specific responses in primary T cells and immortalized T cells is confounded by the presence of endogenous TCR expression which results in mixed alpha/beta TCR pairings and compresses assay readouts. Herein, we describe the development of a novel cell-based TCR knockout (TCR-KO) reporter assay platform for the development and characterization of T-cell redirecting therapies. CRISPR/Cas9 was used to knockout the endogenous TCR chains in Jurkat cells stably expressing a human interleukin-2 promoter-driven luciferase reporter gene to measure TCR signaling. Reintroduction of a transgenic TCR into the TCR-KO reporter cells results in robust antigen-specific reporter activation compared with parental reporter cells. The further development of CD4/CD8 double-positive and double-negative versions enabled low-avidity and high-avidity TCR screening with or without major histocompatibility complex bias. Furthermore, stable TCR-expressing reporter cells generated from TCR-KO reporter cells exhibit sufficient sensitivity to probe in vitro T-cell immunogenicity of protein and nucleic acid-based vaccines. Therefore, our data demonstrated that TCR-KO reporter cells can be a useful tool for the discovery, characterization, and deployment of T-cell immunotherapy.
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4
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Tang H, Zhu L, Zhao X, Jiang X, Zhang J, Pei C, Li L, Kong X. Characterization of CD3γ/δ gene and its immune response in Qihe crucian carp Carassius auratus after challenged by Aeromonas veronii and Poly(I:C). FISH & SHELLFISH IMMUNOLOGY 2023; 133:108550. [PMID: 36646341 DOI: 10.1016/j.fsi.2023.108550] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/23/2022] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
CD3γ/δ found in non-mammalian vertebrates is a CD3 homolog with structural characteristics similar to both mammalian CD3γ and CD3δ, and plays important roles in T cell recognization and immune response in fish. In this study, the full-length of CD3γ/δ from Qihe crucian carp (named CaCD3γ/δ) was cloned and characterized, then the expression response profiles and potential immune functions was explored after Aeromonas veronii and Poly(I:C) challenge. The results showed that the full-length of CaCD3γ/δ was 819 bp including a 5'-UTR of 141 bp, a 3'-UTR of 168 bp, and an ORF of 510 bp encoding a putative 169-aa protein with an estimated MW of 18.71 kD and a theoretical pI of 8.77. The protein sequence of CaCD3γ/δ contained a Leu-Leu and a CXXXC motif in the extracellular domain, and an ITAM and a Leu-Ile motif in the cytoplasm, and a residue of Asn in the transmembrane. CaCD3γ/δ was constitutively expressed in the spleen, liver, gill, and blood of Qihe crucian carp. After the carp were challenged with Poly(I:C) and Aeromonas veronii, the mRNA expression levels of CaCD3γ/δ were significantly changed in the spleen, head kidney, intestine and gill, according to the results of qPCR. However, compared with A. veronii, Poly(I:C) challenge can rapidly induce the CaCD3γ/δ expression levels in head kidney, intestine and spleen, which suggested CaCD3γ/δ may be differentially modulated by different pathogens. Moreover, the results of immunohistochemical analysis showed that the CaCD3γ/δ+ secreted cells in the spleen and gills of Qihe crucian were increased after challenged with Poly(I:C), as well as the spleen challenged with A. veronii, but at different levels. Combined with the fact that vascular congestion, necrosis of parenchymal cells, and inflammatory cells including lymphocytes infiltration were also observed in the gill and spleen of Qihe crucian carp treated with A. veronii and Poly(I:C) revealed by pathological analysis, it was predicted that CaCD3γ/δ+ T lymphocytes may participated in the immune response against pathogens. This study will contribute to understand the important role of CaCD3γ/δ+ T lymphocytes in the immune response of Qihe crucian carp, and provide new insights for the prevention and treatment of the diseases of Qihe crucian carp.
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Affiliation(s)
- Hairong Tang
- College of Life Science, Henan Normal University, Henan province, PR China; Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Lei Zhu
- College of Life Science, Henan Normal University, Henan province, PR China; Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Xianliang Zhao
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Xinyu Jiang
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Jie Zhang
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Chao Pei
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Li Li
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China
| | - Xianghui Kong
- College of Life Science, Henan Normal University, Henan province, PR China; Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Henan province, PR China.
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5
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Takahashi H, Kühtreiber WM, Keefe RC, Lee AH, Aristarkhova A, Dias HF, Ng N, Nelson KJ, Bien S, Scheffey D, Faustman DL. BCG vaccinations drive epigenetic changes to the human T cell receptor: Restored expression in type 1 diabetes. SCIENCE ADVANCES 2022; 8:eabq7240. [PMID: 36383663 PMCID: PMC9668301 DOI: 10.1126/sciadv.abq7240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
The BCG (Bacille Calmette-Guérin) vaccine, introduced 100 years ago for tuberculosis prevention, has emerging therapeutic off-target benefits for autoimmunity. In randomized controlled trials, BCG vaccinations were shown to gradually improve two autoimmune conditions, type 1 diabetes (T1D) and multiple sclerosis. Here, we investigate the mechanisms behind the autoimmune benefits and test the hypothesis that this microbe synergy could be due to an impact on the host T cell receptor (TCR) and TCR signal strength. We show a quantitative TCR defect in T1D subjects consisting of a marked reduction in receptor density on T cells due to hypermethylation of TCR-related genes. BCG corrects this defect gradually over 3 years by demethylating hypermethylated sites on members of the TCR gene family. The TCR sequence is not modified through recombination, ruling out a qualitative defect. These findings support an underlying density defect in the TCR affecting TCR signal strength in T1D.
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Affiliation(s)
- Hiroyuki Takahashi
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Willem M. Kühtreiber
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Ryan C. Keefe
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Amanda H. Lee
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Anna Aristarkhova
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Hans F. Dias
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Nathan Ng
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Kacie J. Nelson
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | | | | | - Denise L. Faustman
- Immunobiology Department, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
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6
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Pishesha N, Harmand TJ, Ploegh HL. A guide to antigen processing and presentation. Nat Rev Immunol 2022; 22:751-764. [PMID: 35418563 DOI: 10.1038/s41577-022-00707-2] [Citation(s) in RCA: 224] [Impact Index Per Article: 112.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2022] [Indexed: 12/13/2022]
Abstract
Antigen processing and presentation are the cornerstones of adaptive immunity. B cells cannot generate high-affinity antibodies without T cell help. CD4+ T cells, which provide such help, use antigen-specific receptors that recognize major histocompatibility complex (MHC) molecules in complex with peptide cargo. Similarly, eradication of virus-infected cells often depends on cytotoxic CD8+ T cells, which rely on the recognition of peptide-MHC complexes for their action. The two major classes of glycoproteins entrusted with antigen presentation are the MHC class I and class II molecules, which present antigenic peptides to CD8+ T cells and CD4+ T cells, respectively. This Review describes the essentials of antigen processing and presentation. These pathways are divided into six discrete steps that allow a comparison of the various means by which antigens destined for presentation are acquired and how the source proteins for these antigens are tagged for degradation, destroyed and ultimately displayed as peptides in complex with MHC molecules for T cell recognition.
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Affiliation(s)
- Novalia Pishesha
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.,Society of Fellows, Harvard University, Cambridge, MA, USA.,Klarman Cell Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Thibault J Harmand
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hidde L Ploegh
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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7
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De Silva D, Ferguson L, Chin GH, Smith BE, Apathy RA, Roth TL, Blaeschke F, Kudla M, Marson A, Ingolia NT, Cate JHD. Robust T cell activation requires an eIF3-driven burst in T cell receptor translation. eLife 2021; 10:e74272. [PMID: 34970966 PMCID: PMC8758144 DOI: 10.7554/elife.74272] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
Activation of T cells requires a rapid surge in cellular protein synthesis. However, the role of translation initiation in the early induction of specific genes remains unclear. Here, we show human translation initiation factor eIF3 interacts with select immune system related mRNAs including those encoding the T cell receptor (TCR) subunits TCRA and TCRB. Binding of eIF3 to the TCRA and TCRB mRNA 3'-untranslated regions (3'-UTRs) depends on CD28 coreceptor signaling and regulates a burst in TCR translation required for robust T cell activation. Use of the TCRA or TCRB 3'-UTRs to control expression of an anti-CD19 chimeric antigen receptor (CAR) improves the ability of CAR-T cells to kill tumor cells in vitro. These results identify a new mechanism of eIF3-mediated translation control that can aid T cell engineering for immunotherapy applications.
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Affiliation(s)
- Dasmanthie De Silva
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
- The J. David Gladstone InstitutesSan FranciscoUnited States
| | - Lucas Ferguson
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
| | - Grant H Chin
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
| | - Benjamin E Smith
- School of Optometry, University of California, BerkeleyBerkeleyUnited States
| | - Ryan A Apathy
- Department of Microbiology and Immunology, University of California, San FranciscoSan FranciscoUnited States
| | - Theodore L Roth
- Department of Microbiology and Immunology, University of California, San FranciscoSan FranciscoUnited States
| | | | - Marek Kudla
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
| | - Alexander Marson
- Department of Microbiology and Immunology, University of California, San FranciscoSan FranciscoUnited States
- Gladstone-UCSF Institute of Genomic ImmunologySan FranciscoUnited States
- Diabetes Center, University of California, San FranciscoSan FranciscoUnited States
- Chan Zuckerberg BiohubSan FranciscoUnited States
- Department of Medicine, University of California, San FranciscoSan FranciscoUnited States
- Parker Institute for Cancer ImmunotherapySan FranciscoUnited States
- Innovative Genomics Institute, University of California, BerkeleyBerkeleyUnited States
| | - Nicholas T Ingolia
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences, University of California, BerkeleyBerkeleyUnited States
| | - Jamie HD Cate
- Department of Molecular and Cell Biology, University of California-BerkeleyBerkeleyUnited States
- The J. David Gladstone InstitutesSan FranciscoUnited States
- Innovative Genomics Institute, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences, University of California, BerkeleyBerkeleyUnited States
- Department of Chemistry, University of California-BerkeleyBerkeleyUnited States
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
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8
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Zhu Y, Huang D, Zhao Z, Lu C. Bioinformatic analysis identifies potential key genes of epilepsy. PLoS One 2021; 16:e0254326. [PMID: 34555062 PMCID: PMC8459949 DOI: 10.1371/journal.pone.0254326] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/31/2021] [Indexed: 12/19/2022] Open
Abstract
Background Epilepsy is one of the most common brain disorders worldwide. It is usually hard to be identified properly, and a third of patients are drug-resistant. Genes related to the progression and prognosis of epilepsy are particularly needed to be identified. Methods In our study, we downloaded the Gene Expression Omnibus (GEO) microarray expression profiling dataset GSE143272. Differentially expressed genes (DEGs) with a fold change (FC) >1.2 and a P-value <0.05 were identified by GEO2R and grouped in male, female and overlapping DEGs. Functional enrichment analysis and Protein-Protein Interaction (PPI) network analysis were performed. Results In total, 183 DEGs overlapped (77 ups and 106 downs), 302 DEGs (185 ups and 117 downs) in the male dataset, and 750 DEGs (464 ups and 286 downs) in the female dataset were obtained from the GSE143272 dataset. These DEGs were markedly enriched under various Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) terms. 16 following hub genes were identified based on PPI network analysis: ADCY7, C3AR1, DEGS1, CXCL1 in male-specific DEGs, TOLLIP, ORM1, ELANE, QPCT in female-specific DEGs and FCAR, CD3G, CLEC12A, MOSPD2, CD3D, ALDH3B1, GPR97, PLAUR in overlapping DEGs. Conclusion This discovery-driven study may be useful to provide a novel insight into the diagnosis and treatment of epilepsy. However, more experiments are needed in the future to study the functional roles of these genes in epilepsy.
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Affiliation(s)
- Yike Zhu
- Department of Respiratory Medicine, Hainan General Hospital, Haikou, China
| | - Dan Huang
- Department of Neurology, Hainan General Hospital, Haikou, China
| | - Zhongyan Zhao
- Department of Neurology, Hainan General Hospital, Haikou, China
| | - Chuansen Lu
- Department of Neurology, Hainan General Hospital, Haikou, China
- * E-mail:
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9
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Kaiser FM, Reisli I, Pico-Knijnenburg I, Langerak AW, Kavelaars FG, Artac H, IJspeert H, van der Burg M. Protein functionality as a potential bottleneck for somatic revertant variants. J Allergy Clin Immunol 2021; 147:391-393.e8. [DOI: 10.1016/j.jaci.2020.04.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/26/2020] [Accepted: 04/30/2020] [Indexed: 12/27/2022]
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10
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Ramesh S, Park S, Call MJ, Im W, Call ME. Experimentally Guided Computational Methods Yield Highly Accurate Insights into Transmembrane Interactions within the T Cell Receptor Complex. J Phys Chem B 2020; 124:10303-10310. [PMID: 33030343 DOI: 10.1021/acs.jpcb.0c06403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding how molecular interactions within the plasma membrane govern assembly, clustering, and conformational changes in single-pass transmembrane (TM) receptors has long presented substantial experimental challenges. Our previous work on activating immune receptors has combined direct biochemical and biophysical characterizations with both independent and experimentally restrained computational methods to provide novel insights into the key TM interactions underpinning assembly and stability of complex, multisubunit receptor systems. The recently published cryo-EM structure of the intact T cell receptor (TCR)-CD3 complex provides a unique opportunity to test the models and predictions arising from these studies, and we find that they are accurate, which we attribute to robust simulation environments and careful consideration of limitations related to studying TM interactions in isolation from additional receptor domains. With this in mind, we revisit results in other immune receptors and look forward to how similar methods may be applied to understand receptors for which little or no structural information is currently available.
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Affiliation(s)
- Samyuktha Ramesh
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Soohyung Park
- Departments of Biological Sciences, Chemistry, Bioengineering, and Computer Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Melissa J Call
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Wonpil Im
- Departments of Biological Sciences, Chemistry, Bioengineering, and Computer Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Matthew E Call
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
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11
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Chandler NJ, Call MJ, Call ME. T Cell Activation Machinery: Form and Function in Natural and Engineered Immune Receptors. Int J Mol Sci 2020; 21:E7424. [PMID: 33050044 PMCID: PMC7582382 DOI: 10.3390/ijms21197424] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/05/2020] [Accepted: 10/07/2020] [Indexed: 12/15/2022] Open
Abstract
The impressive success of chimeric antigen receptor (CAR)-T cell therapies in treating advanced B-cell malignancies has spurred a frenzy of activity aimed at developing CAR-T therapies for other cancers, particularly solid tumors, and optimizing engineered T cells for maximum clinical benefit in many different disease contexts. A rapidly growing body of design work is examining every modular component of traditional single-chain CARs as well as expanding out into many new and innovative engineered immunoreceptor designs that depart from this template. New approaches to immune cell and receptor engineering are being reported with rapidly increasing frequency, and many recent high-quality reviews (including one in this special issue) provide comprehensive coverage of the history and current state of the art in CAR-T and related cellular immunotherapies. In this review, we step back to examine our current understanding of the structure-function relationships in natural and engineered lymphocyte-activating receptors, with an eye towards evaluating how well the current-generation CAR designs recapitulate the most desirable features of their natural counterparts. We identify key areas that we believe are under-studied and therefore represent opportunities to further improve our grasp of form and function in natural and engineered receptors and to rationally design better therapeutics.
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Affiliation(s)
- Nicholas J. Chandler
- Structural Biology Division, Walter and Eliza Hall Institute, Parkville, VIC 3052, Australia; (N.J.C.); (M.J.C.)
- Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Melissa J. Call
- Structural Biology Division, Walter and Eliza Hall Institute, Parkville, VIC 3052, Australia; (N.J.C.); (M.J.C.)
- Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Matthew E. Call
- Structural Biology Division, Walter and Eliza Hall Institute, Parkville, VIC 3052, Australia; (N.J.C.); (M.J.C.)
- Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
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12
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Kwesi-Maliepaard EM, Aslam MA, Alemdehy MF, van den Brand T, McLean C, Vlaming H, van Welsem T, Korthout T, Lancini C, Hendriks S, Ahrends T, van Dinther D, den Haan JMM, Borst J, de Wit E, van Leeuwen F, Jacobs H. The histone methyltransferase DOT1L prevents antigen-independent differentiation and safeguards epigenetic identity of CD8 + T cells. Proc Natl Acad Sci U S A 2020; 117:20706-20716. [PMID: 32764145 PMCID: PMC7456197 DOI: 10.1073/pnas.1920372117] [Citation(s) in RCA: 24] [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] [Indexed: 12/21/2022] Open
Abstract
Cytotoxic T cell differentiation is guided by epigenome adaptations, but how epigenetic mechanisms control lymphocyte development has not been well defined. Here we show that the histone methyltransferase DOT1L, which marks the nucleosome core on active genes, safeguards normal differentiation of CD8+ T cells. T cell-specific ablation of Dot1L resulted in loss of naïve CD8+ T cells and premature differentiation toward a memory-like state, independent of antigen exposure and in a cell-intrinsic manner. Mechanistically, DOT1L controlled CD8+ T cell differentiation by ensuring normal T cell receptor density and signaling. DOT1L also maintained epigenetic identity, in part by indirectly supporting the repression of developmentally regulated genes. Finally, deletion of Dot1L in T cells resulted in an impaired immune response. Through our study, DOT1L is emerging as a central player in physiology of CD8+ T cells, acting as a barrier to prevent premature differentiation and controlling epigenetic integrity.
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Affiliation(s)
| | - Muhammad Assad Aslam
- Division of Tumor Biology and Immunology, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, 60800 Multan, Pakistan
| | - Mir Farshid Alemdehy
- Division of Tumor Biology and Immunology, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Teun van den Brand
- Division of Gene Regulation, Oncode Institute, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Chelsea McLean
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Hanneke Vlaming
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Tibor van Welsem
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Tessy Korthout
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Cesare Lancini
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Sjoerd Hendriks
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Tomasz Ahrends
- Division of Tumor Biology and Immunology, Oncode Institute, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Dieke van Dinther
- Department of Molecular Cell Biology and Immunology, Amsterdam University Medical Center (UMC), Vrije Universiteit Amsterdam, 1081HV Amsterdam, The Netherlands
| | - Joke M M den Haan
- Department of Molecular Cell Biology and Immunology, Amsterdam University Medical Center (UMC), Vrije Universiteit Amsterdam, 1081HV Amsterdam, The Netherlands
| | - Jannie Borst
- Division of Tumor Biology and Immunology, Oncode Institute, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Elzo de Wit
- Division of Gene Regulation, Oncode Institute, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Fred van Leeuwen
- Division of Gene Regulation, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands;
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, 1105AZ Amsterdam, The Netherlands
| | - Heinz Jacobs
- Division of Tumor Biology and Immunology, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands;
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13
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Silva FRD, Guerreiro RDC, Andrade HDA, Stieler E, Silva A, de Mello MT. Does the compromised sleep and circadian disruption of night and shiftworkers make them highly vulnerable to 2019 coronavirus disease (COVID-19)? Chronobiol Int 2020; 37:607-617. [PMID: 32432519 DOI: 10.1080/07420528.2020.1756841] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Rotating and permanent night shiftwork schedules typically result in acute and sometimes chronic sleep deprivation plus acute and sometimes chronic disruption of the circadian time structure. Immune system processes and functionalities are organized as circadian rhythms, and they are also strongly influenced by sleep status. Sleep is a vital behavioral state of living beings and a modulator of immune function and responsiveness. Shiftworkers show increased risk for developing viral infections due to possible compromise of both innate and acquired immunity responses. Short sleep and sleep loss, common consequences of shiftwork, are associated with altered integrity of the immune system. We discuss the possible excess risk for COVID-19 infection in the context of the common conditions among shiftworkers, including nurses, doctors, and first responders, among others of high exposure to the contagion, of sleep imbalance and circadian disruption. ABBREVIATIONS ACE2: Angiotensin-converting enzyme 2; APC: Antigen.-presenting .cells; CCL: Chemokine (C-C motif) ligand; CD+: .Adhesion molecule expression; COVID-19: 2019 coronavirus disease; DCs: Dendritic cells; GH: Growth hormone; HPA: Hypothalamic-pituitary-adrenal; HSF: Heat shock factor; HSP70: Heat shock protein 70; HSP90: Heat shock protein 90; IL: Interleukin; INFγ: Interferon-gamma; LT/LB: T/B lymphocytes; MHC: Major histocompatibility complex; NK: Natural .killer; RAAS: renin-angiotensin-aldosterone system; SARS: .Severe acute respiratory syndrome; SCN: Suprachiasmatic nucleus;SD: Sleep deprivation; SNS: Sympathetic nervous system; Th1/Th2: T helper lymphocytes 1/2; TLR2/TLR4: Toll-like receptor 2/4; TNF-α: Tumor .necrosis .factor alpha; VEGF: Vascular endothelial growth factor.
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Affiliation(s)
| | | | | | - Eduardo Stieler
- Department of Sports, Universidade Federal de Minas Gerais , Belo Horizonte, Brazil
| | - Andressa Silva
- Department of Sports, Universidade Federal de Minas Gerais , Belo Horizonte, Brazil
| | - Marco Túlio de Mello
- Department of Sports, Universidade Federal de Minas Gerais , Belo Horizonte, Brazil
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14
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Lee WI, Fan WL, Lu CH, Chen SH, Kuo ML, Lin SJ, Tsai WS, Jaing TH, Chen LC, Yeh KW, Yao TC, Huang JL. A Novel CD3G Mutation in a Taiwanese Patient With Normal T Regulatory Function Presenting With the CVID Phenotype Free of Autoimmunity-Analysis of all Genotypes and Phenotypes. Front Immunol 2019; 10:2833. [PMID: 31921117 PMCID: PMC6930882 DOI: 10.3389/fimmu.2019.02833] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 11/18/2019] [Indexed: 12/03/2022] Open
Abstract
The T-cell receptor (TCR)/CD3 complex is crucial for T-cell development and regulation. In humans, CD3D, CD3E, and CD3Z gene defects cause severe combined T- and B-cell immunodeficiency. However, CD3G mutations alone lead to a less severe condition, which is mainly characterized by autoimmunity. In the present study, we report the case of a 36-year-old male who presented with recurrent sinopulmonary infections without opportunistic infections; this was compatible with hypogammaglobulinemia, but normal PHA-lymphocyte proliferation. This patient had the common variable immunodeficiency (CVID) phenotype and received regular immunoglobulin infusions over 20-years; he gradually developed nodular regenerative hyperplasia over a 5-year period. Distinct from the previously reported CD3G mutations, which mainly present as autoimmunity, the novel CD3G deletion (c.del213A) in our patient caused an obvious decrease in switched memory B cells and diminished CD40L expression. However, sufficient Treg suppression function was maintained so that he remained free of autoimmune thyroiditis (AIT), inflammatory bowel disease (IBD), and autoimmune pancytopenia. A PubMed search for this rare disease entity revealed seven Turkish and two Spanish patients (five unrelated families). Among a total of 20 alleles, there were 14 splicing mutations (80(-1)G>C), two missense mutations (c.1G>A), two nonsense mutations (c.250A>T), and two deletions (c.del213A). Three patients presented with isolated AIT without significant infections. Three patients died, one from a severe infection at 31 months, one from post-transplant respiratory failure due to viral pneumonia at 17 months, and one from graft-vs.-host disease at 47 months. Those experiencing opportunistic infections, severe life-threatening infections in need of hematopoietic stem cell transplantation, and IBD-like diarrhea had a significantly higher mortality rate compared with those without these features (p = 0.0124, p = 0.01, and p = 0.0124, respectively). The patients with AIT had a significantly better prognosis (p = 0.0124) to those without AIT. Our patient with the novel CD3G mutation presented with predominant B-cell deficiency overlapping with the CVID phenotype but without recognizable autoimmunity, which was consistent with his normal Treg suppression function.
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Affiliation(s)
- Wen-I Lee
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Primary Immunodeficiency Care and Research (PICAR) Institute, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Wen-Lang Fan
- Whole-Genome Research Core Laboratory of Human Diseases, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Chun-Hao Lu
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Shih-Hsiang Chen
- Primary Immunodeficiency Care and Research (PICAR) Institute, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Division of Hematology/Oncology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Ming-Ling Kuo
- Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Syh-Jae Lin
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Weng-Sheng Tsai
- Division of Nephronology, Department of Medicine, Penghu Hospital, Ministry of Health and Welfare, Penghu, Taiwan
| | - Tang-Her Jaing
- Primary Immunodeficiency Care and Research (PICAR) Institute, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Division of Hematology/Oncology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Li-Chen Chen
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Kuo-Wei Yeh
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Tsung-Chieh Yao
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Jing-Long Huang
- Division of Allergy, Asthma and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan.,Primary Immunodeficiency Care and Research (PICAR) Institute, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
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15
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Dube N, Marzinek JK, Glen RC, Bond PJ. The structural basis for membrane assembly of immunoreceptor signalling complexes. J Mol Model 2019; 25:277. [PMID: 31456056 DOI: 10.1007/s00894-019-4165-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 08/15/2019] [Indexed: 11/25/2022]
Abstract
Immunoreceptors are TM complexes that consist of separate ligand-binding and signal-transducing modules. Mounting evidence suggests that interactions with the local environment may influence the architecture of these TM domains, which assemble via crucial sets of conserved ionisable residues, and also control the peripheral association of immunoreceptor tyrosine-based activation motifs (ITAMs) whose phosphorylation triggers cytoplasmic signalling cascades. We now report a molecular dynamics (MD) simulation study of the archetypal T cell receptor (TCR) and its cluster of differentiation 3 (CD3) signalling partners, along with the analogous DNAX-activation protein of 12 kDa (DAP12)/natural killer group 2C (NKG2C) complex. Based on > 15 μs of explicitly solvated, atomic-resolution sampling, we explore molecular aspects of immunoreceptor complex stability in different functionally relevant states. A novel alchemical approach is used to simulate the cytoplasmic CD3ε tail at different depths within lipid bilayer models, revealing that the conformation and cytoplasmic exposure of ITAMs are highly sensitive to local enrichment by different lipid species and to phosphorylation. Furthermore, simulations of the TCR and DAP12 TM domains in various states of oligomerisation suggest that, during the early stages of assembly, stable membrane insertion is facilitated by the interfacial lipid/solvent environment and/or partial ionisation of charged residues. Collectively, our results indicate that the architecture and mechanisms of signal transduction in immunoreceptor complexes are tightly regulated by interactions with the microenvironment.
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Affiliation(s)
- Namita Dube
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Tata Institute of Fundamental Research, 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad, 500107, India
| | - Jan K Marzinek
- Bioinformatics Institute (A*STAR), 30 Biopolis Str., #07-01 Matrix, Singapore, 138671, Singapore
| | - Robert C Glen
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Division of Integrative Systems Medicine and Digestive Diseases, Department of Surgery and Cancer, Imperial College London, London, UK
| | - Peter J Bond
- Bioinformatics Institute (A*STAR), 30 Biopolis Str., #07-01 Matrix, Singapore, 138671, Singapore.
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
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16
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Yousefi OS, Günther M, Hörner M, Chalupsky J, Wess M, Brandl SM, Smith RW, Fleck C, Kunkel T, Zurbriggen MD, Höfer T, Weber W, Schamel WW. Optogenetic control shows that kinetic proofreading regulates the activity of the T cell receptor. eLife 2019; 8:42475. [PMID: 30947807 PMCID: PMC6488296 DOI: 10.7554/elife.42475] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 03/05/2019] [Indexed: 12/18/2022] Open
Abstract
The immune system distinguishes between self and foreign antigens. The kinetic proofreading (KPR) model proposes that T cells discriminate self from foreign ligands by the different ligand binding half-lives to the T cell receptor (TCR). It is challenging to test KPR as the available experimental systems fall short of only altering the binding half-lives and keeping other parameters of the interaction unchanged. We engineered an optogenetic system using the plant photoreceptor phytochrome B (PhyB) as a ligand to selectively control the dynamics of ligand binding to the TCR by light. This opto-ligand-TCR system was combined with the unique property of PhyB to continuously cycle between the binding and non-binding states under red light, with the light intensity determining the cycling rate and thus the binding duration. Mathematical modeling of our experimental datasets showed that indeed the ligand-TCR interaction half-life is the decisive factor for activating downstream TCR signaling, substantiating KPR.
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Affiliation(s)
- O Sascha Yousefi
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine, University of Freiburg, Freiburg, Germany
| | - Matthias Günther
- Division of Theoretical Systems Biology, German Cancer Research Center, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Maximilian Hörner
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Julia Chalupsky
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany.,Center for Chronic Immunodeficiency, Medical Center Freiburg and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Maximilian Wess
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Simon M Brandl
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Robert W Smith
- Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Wageningen, Netherlands
| | - Christian Fleck
- Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Wageningen, Netherlands
| | - Tim Kunkel
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Matias D Zurbriggen
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany.,Institute of Synthetic Biology and Cluster of Excellence on Plant Sciences, University of Düsseldorf, Düsseldorf, Germany
| | - Thomas Höfer
- Division of Theoretical Systems Biology, German Cancer Research Center, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Wilfried Weber
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Wolfgang Wa Schamel
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany.,Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Wageningen, Netherlands
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17
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Goyette J, Nieves DJ, Ma Y, Gaus K. How does T cell receptor clustering impact on signal transduction? J Cell Sci 2019; 132:132/4/jcs226423. [DOI: 10.1242/jcs.226423] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
ABSTRACT
The essential function of the T cell receptor (TCR) is to translate the engagement of peptides on the major histocompatibility complex (pMHC) into appropriate intracellular signals through the associated cluster of differentiation 3 (CD3) complex. The spatial organization of the TCR–CD3 complex in the membrane is thought to be a key regulatory element of signal transduction, raising the question of how receptor clustering impacts on TCR triggering. How signal transduction at the TCR–CD3 complex encodes the quality and quantity of pMHC molecules is not fully understood. This question can be approached by reconstituting T cell signaling in model and cell membranes and addressed by single-molecule imaging of endogenous proteins in T cells. We highlight such methods and further discuss how TCR clustering could affect pMHC rebinding rates, the local balance between kinase and phosphatase activity and/or the lipid environment to regulate the signal efficiency of the TCR–CD3 complex. We also examine whether clustering could affect the conformation of cytoplasmic CD3 tails through a biophysical mechanism. Taken together, we highlight how the spatial organization of the TCR–CD3 complex – addressed by reconstitution approaches – has emerged as a key regulatory element in signal transduction of this archetypal immune receptor.
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Affiliation(s)
- Jesse Goyette
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney 2052, Australia
- ARC Centre of Excellence in Advanced Molecular imaging, University of New South Wales, Sydney 2052, Australia
| | - Daniel J. Nieves
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney 2052, Australia
- ARC Centre of Excellence in Advanced Molecular imaging, University of New South Wales, Sydney 2052, Australia
| | - Yuanqing Ma
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney 2052, Australia
- ARC Centre of Excellence in Advanced Molecular imaging, University of New South Wales, Sydney 2052, Australia
| | - Katharina Gaus
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney 2052, Australia
- ARC Centre of Excellence in Advanced Molecular imaging, University of New South Wales, Sydney 2052, Australia
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18
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Jiang J, Natarajan K, Margulies DH. MHC Molecules, T cell Receptors, Natural Killer Cell Receptors, and Viral Immunoevasins-Key Elements of Adaptive and Innate Immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1172:21-62. [PMID: 31628650 DOI: 10.1007/978-981-13-9367-9_2] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Molecules encoded by the Major Histocompatibility Complex (MHC) bind self or foreign peptides and display these at the cell surface for recognition by receptors on T lymphocytes (designated T cell receptors-TCR) or on natural killer (NK) cells. These ligand/receptor interactions govern T cell and NK cell development as well as activation of T memory and effector cells. Such cells participate in immunological processes that regulate immunity to various pathogens, resistance and susceptibility to cancer, and autoimmunity. The past few decades have witnessed the accumulation of a huge knowledge base of the molecular structures of MHC molecules bound to numerous peptides, of TCRs with specificity for many different peptide/MHC (pMHC) complexes, of NK cell receptors (NKR), of MHC-like viral immunoevasins, and of pMHC/TCR and pMHC/NKR complexes. This chapter reviews the structural principles that govern peptide/MHC (pMHC), pMHC/TCR, and pMHC/NKR interactions, for both MHC class I (MHC-I) and MHC class II (MHC-II) molecules. In addition, we discuss the structures of several representative MHC-like molecules. These include host molecules that have distinct biological functions, as well as virus-encoded molecules that contribute to the evasion of the immune response.
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Affiliation(s)
- Jiansheng Jiang
- Molecular Biology Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bldg. 10, Room 11D07, 10 Center Drive, Bethesda, MD, 20892-1892, USA.
| | - Kannan Natarajan
- Molecular Biology Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bldg. 10, Room 11D07, 10 Center Drive, Bethesda, MD, 20892-1892, USA
| | - David H Margulies
- Molecular Biology Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bldg. 10, Room 11D12, 10 Center Drive, Bethesda, MD, 20892-1892, USA
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19
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Rowe JH, Delmonte OM, Keles S, Stadinski BD, Dobbs AK, Henderson LA, Yamazaki Y, Allende LM, Bonilla FA, Gonzalez-Granado LI, Celikbilek Celik S, Guner SN, Kapakli H, Yee C, Pai SY, Huseby ES, Reisli I, Regueiro JR, Notarangelo LD. Patients with CD3G mutations reveal a role for human CD3γ in T reg diversity and suppressive function. Blood 2018; 131:2335-2344. [PMID: 29653965 PMCID: PMC5969384 DOI: 10.1182/blood-2018-02-835561] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 04/09/2018] [Indexed: 02/05/2023] Open
Abstract
Integrity of the T-cell receptor/CD3 complex is crucial for positive and negative selection of T cells in the thymus and for effector and regulatory functions of peripheral T lymphocytes. In humans, CD3D, CD3E, and CD3Z gene defects are a cause of severe immune deficiency and present early in life with increased susceptibility to infections. By contrast, CD3G mutations lead to milder phenotypes, mainly characterized by autoimmunity. However, the role of CD3γ in establishing and maintaining immune tolerance has not been elucidated. In this manuscript, we aimed to investigate abnormalities of T-cell repertoire and function in patients with genetic defects in CD3G associated with autoimmunity. High throughput sequencing was used to study composition and diversity of the T-cell receptor β (TRB) repertoire in regulatory T cells (Tregs), conventional CD4+ (Tconv), and CD8+ T cells from 6 patients with CD3G mutations and healthy controls. Treg function was assessed by studying its ability to suppress proliferation of Tconv cells. Treg cells of patients with CD3G defects had reduced diversity, increased clonality, and reduced suppressive function. The TRB repertoire of Tconv cells from patients with CD3G deficiency was enriched for hydrophobic amino acids at positions 6 and 7 of the CDR3, a biomarker of self-reactivity. These data demonstrate that the T-cell repertoire of patients with CD3G mutations is characterized by a molecular signature that may contribute to the increased rate of autoimmunity associated with this condition.
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Affiliation(s)
- Jared H Rowe
- Division of Hematology-Oncology, Boston Children's Hospital, Boston, MA
| | - Ottavia M Delmonte
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Sevgi Keles
- Division of Pediatric Immunology and Allergy, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey
| | - Brian D Stadinski
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA
| | - Adam K Dobbs
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | | | - Yasuhiro Yamazaki
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | | | | | - Luis I Gonzalez-Granado
- Primary Immunodeficiencies Unit, Department of Pediatrics, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Seyma Celikbilek Celik
- Division of Pediatric Immunology and Allergy, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey
| | - Sukru N Guner
- Division of Pediatric Immunology and Allergy, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey
| | - Hasan Kapakli
- Division of Pediatric Immunology and Allergy, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey
| | - Christina Yee
- Division of Immunology, Boston Children's Hospital, Boston, MA
| | - Sung-Yun Pai
- Division of Hematology-Oncology, Boston Children's Hospital, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA; and
| | - Eric S Huseby
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA
| | - Ismail Reisli
- Division of Pediatric Immunology and Allergy, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey
| | - Jose R Regueiro
- Department of Immunology, Complutense University School of Medicine, imas12 Research Institute, Madrid, Spain
| | - Luigi D Notarangelo
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
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20
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Structural Conservation and Effects of Alterations in T Cell Receptor Transmembrane Interfaces. Biophys J 2018; 114:1030-1035. [PMID: 29395047 DOI: 10.1016/j.bpj.2018.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/21/2017] [Accepted: 01/05/2018] [Indexed: 11/20/2022] Open
Abstract
T cell receptors (TCRs) are octameric assemblies of type-I membrane proteins in which a receptor heterodimer (αβ, δγ, or pre-Tαβ) is associated with three dimeric signaling modules (CD3δε, CD3γε, and ζζ) at the T cell or pre-T cell surface. In the human αβTCR, the α and β transmembrane (TM) domains form a specific structure that acts as a hub for assembly with the signaling modules inside the lipid bilayer. Conservation of key polar contacts across the C-terminal half of this TM interface suggests that the structure is a common feature of all TCR types. In this study, using molecular dynamics simulations in explicit lipid bilayers, we show that human δγ and pre-Tαβ TM domains also adopt stable αβ-like interfaces, yet each displays unique features that modulate the stability of the interaction and are related to sequences that are conserved within TCR types, but are distinct from the αβ sequences. We also performed simulations probing effects of previously reported mutations in the human αβ TM interface, and observed that the most disruptive mutations caused substantial departures from the wild-type TM structure and increased dynamics. These simulations show a strong correlation between structural instability, increased conformational variation, and the severity of structural defects in whole-TCR complexes measured in our previous biochemical assays. These results thus support the view that the stability of the core TM structure is a key determinant of TCR structural integrity and suggest that the interface has been evolutionarily optimized for different forms of TCRs.
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21
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Effects of Vitamin B6 Deficiency on the Composition and Functional Potential of T Cell Populations. J Immunol Res 2017; 2017:2197975. [PMID: 28367454 PMCID: PMC5358464 DOI: 10.1155/2017/2197975] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/21/2017] [Accepted: 02/14/2017] [Indexed: 11/18/2022] Open
Abstract
The immune system is critical in preventing infection and cancer, and malnutrition can weaken different aspects of the immune system to undermine immunity. Previous studies suggested that vitamin B6 deficiency could decrease serum antibody production with concomitant increase in IL4 expression. However, evidence on whether vitamin B6 deficiency would impair immune cell differentiation, cytokines secretion, and signal molecule expression involved in JAK/STAT signaling pathway to regulate immune response remains largely unknown. The aim of this study is to investigate the effects of vitamin B6 deficiency on the immune system through analysis of T lymphocyte differentiation, IL-2, IL-4, and INF-γ secretion, and SOCS-1 and T-bet gene transcription. We generated a vitamin B6-deficient mouse model via vitamin B6-depletion diet. The results showed that vitamin B6 deficiency retards growth, inhibits lymphocyte proliferation, and interferes with its differentiation. After ConA stimulation, vitamin B6 deficiency led to decrease in IL-2 and increase in IL-4 but had no influence on IFN-γ. Real-time PCR analysis showed that vitamin B6 deficiency downregulated T-bet and upregulated SOCS-1 transcription. This study suggested that vitamin B6 deficiency influenced the immunity in organisms. Meanwhile, the appropriate supplement of vitamin B6 could benefit immunity of the organism.
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22
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Targeting a CAR to the TRAC locus with CRISPR/Cas9 enhances tumour rejection. Nature 2017; 543:113-117. [PMID: 28225754 DOI: 10.1038/nature21405] [Citation(s) in RCA: 1200] [Impact Index Per Article: 171.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 01/20/2017] [Indexed: 12/13/2022]
Abstract
Chimeric antigen receptors (CARs) are synthetic receptors that redirect and reprogram T cells to mediate tumour rejection. The most successful CARs used to date are those targeting CD19 (ref. 2), which offer the prospect of complete remission in patients with chemorefractory or relapsed B-cell malignancies. CARs are typically transduced into the T cells of a patient using γ-retroviral vectors or other randomly integrating vectors, which may result in clonal expansion, oncogenic transformation, variegated transgene expression and transcriptional silencing. Recent advances in genome editing enable efficient sequence-specific interventions in human cells, including targeted gene delivery to the CCR5 and AAVS1 loci. Here we show that directing a CD19-specific CAR to the T-cell receptor α constant (TRAC) locus not only results in uniform CAR expression in human peripheral blood T cells, but also enhances T-cell potency, with edited cells vastly outperforming conventionally generated CAR T cells in a mouse model of acute lymphoblastic leukaemia. We further demonstrate that targeting the CAR to the TRAC locus averts tonic CAR signalling and establishes effective internalization and re-expression of the CAR following single or repeated exposure to antigen, delaying effector T-cell differentiation and exhaustion. These findings uncover facets of CAR immunobiology and underscore the potential of CRISPR/Cas9 genome editing to advance immunotherapies.
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23
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Han NR, Moon PD, Kim NR, Kim HY, Jeong HJ, Kim HM. Schisandra chinensis and Its Main Constituent Schizandrin Attenuate Allergic Reactions by Down-Regulating Caspase-1 in Ovalbumin-Sensitized Mice. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2017; 45:159-172. [DOI: 10.1142/s0192415x17500112] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Schisandra chinensis (SC) and its main constituent, schizandrin (SCH) exhibit anti-inflammatory and anti-allergic activities. Allergic and inflammatory reactions are aggravated via caspase-1 signaling pathway. However, the regulatory effects of SC and SCH on caspase-1 activation have not been clarified yet. In this study, we aimed to clarify the anti-allergic effects of SC and SCH using an ovalbumin (OVA)-sensitized mice and anti-CD3 and anti-CD28 antibodies-stimulated splenocytes. SC or SCH significantly inhibited the levels of immunoglobulin (Ig)E, IgG1, or interleukin (IL)-4 in serum of OVA-sensitized mice. SC or SCH significantly inhibited the levels of IL-6, tumor necrosis factor (TNF)-[Formula: see text], and IL-1[Formula: see text] in spleen of the OVA-sensitized mice. SC or SCH significantly suppressed the expression of caspase-1 and receptor-interacting protein (RIP)-2 in spleen of the OVA-sensitized mice. In activated splenocytes, SC or SCH significantly decreased the expression of caspase-1 and RIP-2 as well as the production of IL-6 and TNF-[Formula: see text]. We suggest that SC and SCH exert an anti-allergic effect by down-regulating caspase-1 signaling.
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Affiliation(s)
- Na-Ra Han
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Phil-Dong Moon
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Na-Rae Kim
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hee-Yun Kim
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hyun-Ja Jeong
- Department of Food Science & Technology and Research Institute for Basic Science, Hoseo University, Chungnam 31499, Republic of Korea
| | - Hyung-Min Kim
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
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24
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Bethune MT, Gee MH, Bunse M, Lee MS, Gschweng EH, Pagadala MS, Zhou J, Cheng D, Heath JR, Kohn DB, Kuhns MS, Uckert W, Baltimore D. Domain-swapped T cell receptors improve the safety of TCR gene therapy. eLife 2016; 5. [PMID: 27823582 PMCID: PMC5101000 DOI: 10.7554/elife.19095] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 10/11/2016] [Indexed: 12/17/2022] Open
Abstract
T cells engineered to express a tumor-specific αβ T cell receptor (TCR) mediate anti-tumor immunity. However, mispairing of the therapeutic αβ chains with endogenous αβ chains reduces therapeutic TCR surface expression and generates self-reactive TCRs. We report a general strategy to prevent TCR mispairing: swapping constant domains between the α and β chains of a therapeutic TCR. When paired, domain-swapped (ds)TCRs assemble with CD3, express on the cell surface, and mediate antigen-specific T cell responses. By contrast, dsTCR chains mispaired with endogenous chains cannot properly assemble with CD3 or signal, preventing autoimmunity. We validate this approach in cell-based assays and in a mouse model of TCR gene transfer-induced graft-versus-host disease. We also validate a related approach whereby replacement of αβ TCR domains with corresponding γδ TCR domains yields a functional TCR that does not mispair. This work enables the design of safer TCR gene therapies for cancer immunotherapy. DOI:http://dx.doi.org/10.7554/eLife.19095.001 T cells enable the immune system to recognize invading microbes and diseased cells while ignoring healthy cells. The ability of a T cell to recognize a specific microbe or diseased cell is determined by two proteins that pair to form its “T cell receptor.” The paired receptors are exported to the surface of the T cell, where they bind to infected or cancerous cells. Those T cells that produce receptors that bind healthy cells are eliminated during development. T cells can generally distinguish between the body’s own cells and the cells of invading bacteria or other microbes. However, cancer cells are more difficult to identify because they are similar to healthy cells. Efforts to develop therapies that enhance the immune system’s ability to recognize cancer cells have had only limited success. One successful approach – known as T cell receptor gene therapy – modifies T cells to destroy cancer cells by arming them with a cancer-specific T cell receptor. This technique produces T cells possessing two T cell receptors – the cancer-specific receptor and the one it had originally – so it is possible for proteins from the two receptors to mispair. This impedes the correct pairing of the cancer-specific T cell receptor, reducing the effectiveness of the therapy. More importantly, mispaired T cell receptors may cause the immune cells to attack healthy cells in the body, leading to autoimmune disease. To make T cell receptor gene therapy safe, the cancer-specific receptor must not mispair with the resident receptor. Here, Bethune et al. describe a new strategy to prevent T cell receptors from mispairing. The researchers altered the arrangement of particular regions in a cancer-specific T cell receptor to make a new receptor called a domain-swapped T cell receptor (dsTCR). Like normal T cell receptors, the dsTCRs were exported to the T cell surface and were able to interact with other proteins involved in immune responses. Furthermore, T cells armed with dsTCRs were able to kill cancer cells and prevent tumor growth in mice. Unlike other cancer-specific receptors, dsTCRs did not mispair with the resident T cell receptors in mouse or human cells, and did not cause autoimmune disease in mice. The findings of Bethune et al. show that the structure of the T cell receptor is unexpectedly robust, in that it still works even if it is modified. The next step is to study dsTCRs in more detail with the aim of optimizing them so that they might be used in human clinical trials in the future. DOI:http://dx.doi.org/10.7554/eLife.19095.002
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Affiliation(s)
- Michael T Bethune
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Marvin H Gee
- Program in Immunology, Stanford University School of Medicine, Stanford, United States
| | - Mario Bunse
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Mark S Lee
- Department of Immunobiology, University of Arizona, Tucson, United States.,The BIO5 Institute, University of Arizona, Tucson, United States
| | - Eric H Gschweng
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, United States
| | - Meghana S Pagadala
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Jing Zhou
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Donghui Cheng
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, United States
| | - James R Heath
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Donald B Kohn
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, United States
| | - Michael S Kuhns
- Department of Immunobiology, University of Arizona, Tucson, United States.,The BIO5 Institute, University of Arizona, Tucson, United States
| | - Wolfgang Uckert
- Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - David Baltimore
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
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25
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A conserved αβ transmembrane interface forms the core of a compact T-cell receptor-CD3 structure within the membrane. Proc Natl Acad Sci U S A 2016; 113:E6649-E6658. [PMID: 27791034 DOI: 10.1073/pnas.1611445113] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The T-cell antigen receptor (TCR) is an assembly of eight type I single-pass membrane proteins that occupies a central position in adaptive immunity. Many TCR-triggering models invoke an alteration in receptor complex structure as the initiating event, but both the precise subunit organization and the pathway by which ligand-induced alterations are transferred to the cytoplasmic signaling domains are unknown. Here, we show that the receptor complex transmembrane (TM) domains form an intimately associated eight-helix bundle organized by a specific interhelical TCR TM interface. The salient features of this core structure are absolutely conserved between αβ and γδ TCR sequences and throughout vertebrate evolution, and mutations at key interface residues caused defects in the formation of stable TCRαβ:CD3δε:CD3γε:ζζ complexes. These findings demonstrate that the eight TCR-CD3 subunits form a compact and precisely organized structure within the membrane and provide a structural basis for further investigation of conformationally regulated models of transbilayer TCR signaling.
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26
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Shi L, Chen S, Zha X, Xu Y, Xu L, Yang L, Lu Y, Zhu K, Li Y. Enhancement of the TCRζ expression, polyclonal expansion, and activation of t cells from patients with acute myeloid leukemia after IL-2, IL-7, and IL-12 induction. DNA Cell Biol 2015; 34:481-8. [PMID: 25757160 PMCID: PMC4504257 DOI: 10.1089/dna.2015.2810] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 02/02/2015] [Accepted: 02/03/2015] [Indexed: 12/28/2022] Open
Abstract
Defective T cell receptor (TCR) signaling resulting in lower T cell function plays a crucial role in the pathogenesis of T cell immunodeficiency in leukemia. Previous studies have indicated that lower TCRζ levels are a common characteristic of patients with leukemia, and upregulating TCRζ could partially recover T cell function. In this study, we characterized the effect of the stimulating factor induction on the TCRζ, Zap-70, and FcɛRIγ levels, IFN-γ secretion, and the distribution and clonal expansion of TCR Vβ subfamilies in CD3(+) T cells sorted from peripheral blood from acute myeloid leukemia (AML) patients. The induction included single stimulating factor or a combination with different cytokines (IL-2, IL-7, IL-2+IL-7, IL-7+IL-12, CD3, CD3+CD28 antibody, CD3+CD28 antibody+IL-2, and CD3+CD28 antibody+IL-7) at 72 h. The results showed that increased TCRζ and Zap-70 levels with deceased FcɛRIγ in T cells after induction, and different responses to cytokine in T cell from different cases may indicate the heterogeneity of T cells and different immune statuses in different AML cases. Increased IFN-γ levels in T cells from AML patients were detected after induction in the IL-12+IL-7, CD3+CD28+IL-2, and CD3+CD28+IL-7 groups. Moreover, the number of TCR Vβ subfamily T cells expressed was increased; however, all of the TCR Vβ subfamily T cells in the AML patients could not be completely recovered after induction. In conclusion, the cytotoxicity and activation function of T cells could be enhanced after induction by different stimuli accompanied by an increase in TCRζ and Zap-70 and recovery of the TCR Vβ repertoire in AML patients.
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Affiliation(s)
- Li Shi
- Institute of Hematology, Jinan University, Guangzhou, China
| | - Shaohua Chen
- Institute of Hematology, Jinan University, Guangzhou, China
| | - Xianfeng Zha
- Department of Clinical Laboratory, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yan Xu
- Institute of Hematology, Jinan University, Guangzhou, China
- Key Laboratory for Regenerative Medicine of Ministry of Education, Jinan University, Guangzhou, China
| | - Ling Xu
- Institute of Hematology, Jinan University, Guangzhou, China
| | - Lijian Yang
- Institute of Hematology, Jinan University, Guangzhou, China
| | - Yuhong Lu
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Kanger Zhu
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yangqiu Li
- Institute of Hematology, Jinan University, Guangzhou, China
- Key Laboratory for Regenerative Medicine of Ministry of Education, Jinan University, Guangzhou, China
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27
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Merulla J, Soldà T, Molinari M. A novel UGGT1 and p97-dependent checkpoint for native ectodomains with ionizable intramembrane residue. Mol Biol Cell 2015; 26:1532-42. [PMID: 25694454 PMCID: PMC4395132 DOI: 10.1091/mbc.e14-12-1615] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/09/2015] [Indexed: 01/01/2023] Open
Abstract
There is unexpected collaboration of the cytosolic AAA-ATPase p97 and the luminal quality control factor UGGT1 in a novel, BiP- and CNX-independent protein quality checkpoint. This prevents Golgi transport of a chimera with a native ectodomain that passes the luminal quality control scrutiny but displays an intramembrane defect. Only native polypeptides are released from the endoplasmic reticulum (ER) to be transported at the site of activity. Persistently misfolded proteins are retained and eventually selected for ER-associated degradation (ERAD). The paradox of a structure-based protein quality control is that functional polypeptides may be destroyed if they are architecturally unfit. This has health-threatening implications, as shown by the numerous “loss-of-function” proteopathies, but also offers chances to intervene pharmacologically to promote bypassing of the quality control inspection and export of the mutant, yet functional protein. Here we challenged the ER of human cells with four modular glycopolypeptides designed to alert luminal and membrane protein quality checkpoints. Our analysis reveals the unexpected collaboration of the cytosolic AAA-ATPase p97 and the luminal quality control factor UDP-glucose:glycoprotein glucosyltransferase (UGGT1) in a novel, BiP- and CNX-independent checkpoint. This prevents Golgi transport of a chimera with a native ectodomain that passes the luminal quality control scrutiny but displays an intramembrane defect. Given that human proteopathies may result from impaired transport of functional polypeptides with minor structural defects, identification of quality checkpoints and treatments to bypass them as shown here upon silencing or pharmacologic inhibition of UGGT1 or p97 may have important clinical implications.
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Affiliation(s)
- Jessica Merulla
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3000 Bern, Switzerland
| | - Tatiana Soldà
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland
| | - Maurizio Molinari
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland Ecole Polytechnique Fédérale de Lausanne, School of Life Sciences, CH-1015 Lausanne, Switzerland
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28
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Gokturk B, Keles S, Kirac M, Artac H, Tokgoz H, Guner SN, Caliskan U, Caliskaner Z, van der Burg M, van Dongen J, Morgan NV, Reisli I. CD3G gene defects in familial autoimmune thyroiditis. Scand J Immunol 2015; 80:354-61. [PMID: 24910257 DOI: 10.1111/sji.12200] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 04/29/2014] [Indexed: 11/27/2022]
Abstract
The patients with CD3γ deficiency can present with different clinical findings despite having the same homozygous mutation. We report three new CD3gamma-deficient siblings from a consanguineous family with a combined T-B+NK+ immunodeficiency and their variable clinical and cellular phenotypes despite the same homozygous mutation of the CD3G gene (c.80-1G>C). We also re-evaluate a previously reported non-consanguineous family with two CD3gamma-deficient siblings with the same mutation. The median age at diagnosis was 11 years (14 months-20 years). We found all five patients to display autoimmunity: autoimmune thyroiditis (n = 5), autoimmune haemolytic anaemia (n = 2), immune thrombocytopenia (n = 1), autoimmune hepatitis (n = 1), minimal change nephrotic syndrome (n = 1), vitiligo (n = 1) and positive antinuclear antibodies (n = 3) as well as high IgE (n = 2) and atopic eczema (n = 2). While CD3(+) TCRαβ+T cell percentages were low in all patients, only one had lymphopenia and 3 had CD3(+) T cell lymphopenia. Strikingly, we report frequent and multiple autoimmunity in tested heterozygous carriers in both families (n = 6; in 67%), and frequent autoimmunity in family members not available for testing (n = 5, in 80%). The results suggest that CD3G should be studied as a candidate gene for autoimmunity and that CD3gamma deficiency should be considered among other primary immunodeficiencies with predominantly autoimmune manifestations.
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Affiliation(s)
- B Gokturk
- Division of Immunology and Allergy, Konya Training and Research Hospital, Konya, Turkey
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29
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Liao Z, Zhou L, Wang C, He Z, Wang X, Luo X, Chen S, Yang L, Tan H, Li Y. Characteristics of TCRζ, ZAP-70, and FcɛRIγ gene expression in patients with T- and NK/T-cell lymphoma. DNA Cell Biol 2014; 34:201-7. [PMID: 25513989 DOI: 10.1089/dna.2014.2693] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Abnormal expression of key signaling molecules and defective T-cell function play a crucial role in the pathogenesis of T-cell immunodeficiency in hematological malignancies. To understand the molecular basis of T-cell signaling abnormalities and TCRζ chain deficiencies in T- and NK/T-cell lymphoma, the expression level of the TCRζ, ZAP-70, and FcɛRIγ genes in peripheral blood mononuclear cells from 25 patients with T-cell lymphoma, 16 patients with NK/T-cell lymphoma (NK/T-CL), and 26 healthy individuals was determined. In addition, their relationship with disease stage and TCRζ 3' untranslated region (3'UTR) splice variants was analyzed in this study. The expression level of all three genes was significantly altered with disease progression, and a decreasing trend was found in patients compared with healthy controls. TCRζ and ZAP-70 were significantly positively related in all samples, and a negative relationship between TCRζ and FcɛRIγ was significantly lost in NK/T-CL patients. Moreover, distinct expression patterns were defined for patient groups with different TCRζ 3'UTR isoforms. In conclusion, a lower expression pattern for all three genes may indicate a weaker immune status based on reduced TCRζ and ZAP-70 expression without the complementary effects of FcɛRIγ, while aberrant TCRζ 3'UTR splicing may contribute to T-cell receptor (TCR) signaling regulation in T cells from patients with T- and NK/T-cell lymphoma.
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Affiliation(s)
- Ziwei Liao
- 1 Institute of Hematology, Jinan University , Guangzhou, China
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30
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Wang W, Li T, Felsovalyi K, Chen C, Cardozo T, Krogsgaard M. Quantitative analysis of T cell receptor complex interaction sites using genetically encoded photo-cross-linkers. ACS Chem Biol 2014; 9:2165-72. [PMID: 25061810 PMCID: PMC4168801 DOI: 10.1021/cb500351s] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
![]()
The T cell receptor (TCR)-cluster
of differentiation 3 (CD3) signaling
complex plays an important role in initiation of adaptive immune responses,
but weak interactions have obstructed delineation of the individual
TCR-CD3 subunit interactions during T cell signaling. Here, we demonstrate
that unnatural amino acids (UAA) can be used to photo-cross-link subunits
of TCR-CD3 on the cell surface. Incorporating UAA in mammalian cells
is usually a low efficiency process. In addition, TCR-CD3 is composed
of eight subunits and both TCR and CD3 chains are required for expression
on the cell surface. Photo-cross-linking of UAAs for studying protein
complexes such as TCR-CD3 is challenging due to the difficulty of
transfecting and expressing multisubunit protein complexes in cells
combined with the low efficiency of UAA incorporation. Here, we demonstrate
that by systematic optimization, we can incorporate UAA in TCR-CD3
with high efficiency. Accordingly, the incorporated UAA can be used
for site-specific photo-cross-linking experiments to pinpoint protein
interaction sites, as well as to confirm interaction sites identified
by X-ray crystallography. We systemically compared two different photo-cross-linkers—p-azido-phenylalanine
(pAzpa) and H-p-Bz-Phe-OH (pBpa)—for their ability to map protein
subunit interactions in the 2B4 TCR. pAzpa was found to have higher
cross-linking efficiency, indicating that optimization of the selection
of the most optimal cross-linker is important for correct identification
of protein–protein interactions. This method is therefore suitable
for studying interaction sites of large, dynamic heteromeric protein
complexes associated with various cellular membrane systems.
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Affiliation(s)
| | | | | | - Chunlai Chen
- Pennsylvania
Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania United States
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31
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Li Y. T-cell immune suppression in patients with hematologic malignancies: clinical implications. Int J Hematol Oncol 2014. [DOI: 10.2217/ijh.14.23] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY The reversion of immune suppression and restoration of T-cell function against leukemia remains a significant clinical challenge. However, the advent of improved antileukemia-specific T-cell induction and the generation of gene-modified T cells has extended cellular immunotherapy to hematological malignancies. Numerous immunotherapeutic protocols have been developed aiming to enhance antileukemia T-cell immune function, eliminate leukemic cells and prevent relapse. By contrast, abnormal expression of CTLA-4 and PD1/PD-L1 plays a critical role in effector T-cell responses and increases Treg suppressive activity in patients with tumors; therefore, blocking CTLA-4, PD1 and PD-L1 is a novel approach for immunotherapy.
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32
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Brazin KN, Mallis RJ, Li C, Keskin DB, Arthanari H, Gao Y, Wu SL, Karger BL, Wagner G, Reinherz EL. Constitutively oxidized CXXC motifs within the CD3 heterodimeric ectodomains of the T cell receptor complex enforce the conformation of juxtaposed segments. J Biol Chem 2014; 289:18880-92. [PMID: 24849600 PMCID: PMC4081929 DOI: 10.1074/jbc.m114.574996] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 05/19/2014] [Indexed: 11/06/2022] Open
Abstract
The CD3ϵγ and CD3ϵδ heterodimers along with the CD3ζζ homodimer are the signaling components of the T cell receptor (TCR). These invariant dimers are non-covalently associated on the T cell plasma membrane with a clone-specific (i.e. clonotypic) αβ heterodimer that binds its cognate ligand, a complex between a particular antigenic peptide, and an MHC molecule (pMHC). These four TCR dimers exist in a 1:1:1:1 stoichiometry. At the junction between the extracellular and transmembrane domains of each mammalian CD3ϵ, CD3γ, and CD3δ subunit is a highly conserved CXXC motif previously found to be important for thymocyte and T cell activation. The redox state of each CXXC motif is presently unknown. Here we show using LC-MS and a biotin switch assay that these CXXC segments are constitutively oxidized on resting and activated T cells, consistent with their measured reduction potential. NMR chemical shift perturbation experiments comparing a native oxidized CD3δ CXXC-containing segment with that of a mutant SXXS-containing CD3δ segment in LPPG (1-palmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt)) micelles show extensive chemical shift differences in residues within the membrane-proximal motif as well as throughout the transmembrane and cytoplasmic domains as a result of the elimination of the native disulfide. Likewise, direct comparison of the native CD3δ segment in oxidizing and reducing conditions reveals numerous spectral differences. The oxidized CXXC maintains the structure within the membrane-proximal stalk region as well as that of its contiguous transmembrane and cytoplasmic domain, inclusive of the ITAM (immunoreceptor tyrosine-based activation motif) involved in signaling. These results suggest that preservation of the CD3 CXXC oxidized state may be essential for TCR mechanotransduction.
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Affiliation(s)
- Kristine N Brazin
- From the Department of Medical Oncology, Laboratory of Immunobiology, Dana-Farber Cancer Institute and Departments of Medicine and
| | - Robert J Mallis
- Biological Chemistry and Molecular Pharmacology, Harvard Medical School and
| | - Chen Li
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, Massachusetts 02115
| | - Derin B Keskin
- From the Department of Medical Oncology, Laboratory of Immunobiology, Dana-Farber Cancer Institute and
| | - Haribabu Arthanari
- Biological Chemistry and Molecular Pharmacology, Harvard Medical School and
| | - Yuanwei Gao
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, Massachusetts 02115
| | - Shiaw-Lin Wu
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, Massachusetts 02115
| | - Barry L Karger
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston, Massachusetts 02115
| | - Gerhard Wagner
- Biological Chemistry and Molecular Pharmacology, Harvard Medical School and
| | - Ellis L Reinherz
- From the Department of Medical Oncology, Laboratory of Immunobiology, Dana-Farber Cancer Institute and Departments of Medicine and
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33
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Niu Y, Yu W, Fang S, Liu S, Yang Z, Liu W, Chen S, Yang L, Li B, Li Y. Lead poisoning influences TCR-related gene expression patterns in peripheral blood T-lymphocytes of exposed workers. J Immunotoxicol 2014; 12:92-7. [PMID: 24720682 DOI: 10.3109/1547691x.2014.899412] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Previous studies have shown that occupational lead (Pb) exposure might influence human T-lymphocyte function, including such as changes in T-cell receptor (TCR) Vβ and Vγ repertoire and in expression of the TCRζ gene. Thus, the study here further investigated expression of TCRζ-related factors and the FcεRIγ gene (whose product has a functional role complementary to the TCRζ chain) and the Elf-1 gene whose product is involved in regulation of TCR expression. Quantitative real-time RT-PCR was used to measure expression of TCRζ, FcεRIγ, and Elf-1 genes in peripheral blood mononuclear cells (PBMC) isolated from 17 Pb-exposed workers. Samples were collected before and after the workers had undergone chelation therapy regimens. Twenty-three healthy individuals served as controls. The results showed that TCRζ, FcεRIγ, and Elf-1 gene expression in Pb-exposed workers before chelation therapy was significantly lower than in PBMC from healthy individuals. After chelation therapy, expression of TCRζ appeared to trend toward normal levels; in comparison, lower expressions of FcεRIγ and Elf-1 persisted. In conclusion, the previously-documented impairment of T-lymphocyte functions and T- lymphocyte-mediated immune responses seen previously in response to occupational Pb exposure might be attributable, in part, to effects on TCR signaling pathways - including those related to TCRζ and FcεRIγ - and to any down-regulation of membrane TCRζ expression/activity that might be associated with Pb-induced effects on Elf-1 expression.
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Affiliation(s)
- Yuzhe Niu
- Institute of Hematology, Medical College, Jinan University , Guangzhou , PR China
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The structure of the CD3ζζ transmembrane dimer in lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:739-46. [PMID: 24333300 DOI: 10.1016/j.bbamem.2013.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 11/26/2013] [Accepted: 12/02/2013] [Indexed: 11/23/2022]
Abstract
Virtually every aspect of the human adaptive immune response is controlled by T cells. The T cell receptor (TCR) complex is responsible for the recognition of foreign peptide sequences, forming the initial step in the elimination of germ-infected cells. The recognition leads to an extracellular conformational change that is transmitted intracellularly through the Cluster of Differentiation 3 (CD3) subunits of the TCR-CD3 complex. Here we address the interplay between the disulfide-linked CD3ζζ dimer, an essential signaling component of the TCR-CD3 complex, and its lipidic environment. The disulfide bond formation requires the absolute presence of a nearby conserved aspartic acid, a fact that has mystified the scientific community. We use atomistic simulation methods to demonstrate that the conserved aspartic acid pair of the CD3ζζ dimer leads to a deformation of the membrane. This deformation changes the local environment of the cysteines and promotes disulfide bond formation. We also investigate the role of a conserved Tyr, highlighting its possible role in the interaction with other transmembrane components of the TCR-CD3 complex.
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Li Y, Chen S, Yang L, Chen S, Lin C, Wang L, Lu Y, Geng S, Du X, Schmidt CA. Change in expression pattern of TCR–CD3 complex in patients with multiple myeloma. Hematology 2013; 16:143-50. [PMID: 21669053 DOI: 10.1179/102453311x12953015767491] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Yangqiu Li
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
- Key Laboratory for Regenerative Medicine of Ministry of EducationMedical College, Jinan University, Guangzhou, China
| | - Shaohua Chen
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
| | - Lijian Yang
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
| | - Si Chen
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
| | - Chunlan Lin
- Department of BiochemistryMedical College, Jinan University, Guangzhou, China
| | - Liang Wang
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
| | - Yuhong Lu
- Institute of HematologyMedical College, Medical College, Jinan University, Guangzhou, China
| | - Suxia Geng
- Department of HematologyGuangdong Province People’s Hospital, Guangzhou, China
| | - Xin Du
- Department of HematologyGuangdong Province People’s Hospital, Guangzhou, China
| | - Christian A Schmidt
- Department of Hematology and OncologyErnst-Moritz-Arndt University Greifswald, Greifswald, Germany
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36
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Matter MS, Schwarz E, Marafioti T, Schraml P, Moch H. Immunohistochemical detection of CD3 in T-cell lymphomas: superior sensitivity of rabbit monoclonal 2GV6 antibody compared to mouse monoclonal F7·2·38 antibody. J Histotechnol 2013. [DOI: 10.1179/2046023612y.0000000017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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37
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Matalon E, Faingold O, Eisenstein M, Shai Y, Goldfarb D. The topology, in model membranes, of the core peptide derived from the T-cell receptor transmembrane domain. Chembiochem 2013; 14:1867-75. [PMID: 23881822 DOI: 10.1002/cbic.201300191] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Indexed: 01/16/2023]
Abstract
The T-cell receptor-CD3 complex (TCR-CD3) serves a critical role in protecting organisms from infectious agents. The TCR is a heterodimer composed of α- and β-chains, which are responsible for antigen recognition. Within the transmembrane domain of the α-subunit, a region has been identified to be crucial for the assembly and function of the TCR. This region, termed core peptide (CP), consists of nine amino acids (GLRILLLKV), two of which are charged (lysine and arginine) and are crucial for the interaction with CD3. Earlier studies have shown that a synthetic peptide corresponding to the CP sequence can suppress the immune response in animal models of T-cell-mediated inflammation, by disrupting proper assembly of the TCR. As a step towards the understanding of the source of the CP activity, we focused on CP in egg phosphatidylcholine/cholesterol (9:1, mol/mol) model membranes and determined its secondary structure, oligomerization state, and orientation with respect to the membrane. To achieve this goal, 15-residue segments of TCRα, containing the CP, were synthesized and spin-labeled at different locations with a nitroxide derivative. Electron spin-echo envelope modulation spectroscopy was used to probe the position and orientation of the peptides within the membrane, and double electron-electron resonance measurements were used to probe its conformation and oligomerization state. We found that the peptide is predominantly helical in a membrane environment and tends to form oligomers (mostly dimers) that are parallel to the membrane plane.
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Affiliation(s)
- Erez Matalon
- Department of Chemical Physics, Weizmann Institute of Science, 234 Hertzl St, Rehovot, 7632700 (Israel)
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38
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Chen S, Yang L, Lu X, Li B, Chan JYH, Cai D, Li Y. Gene expression profiling of CD3γ, δ, ϵ, and ζ chains in CD4+and CD8+T cells from human umbilical cord blood. Hematology 2013; 15:230-5. [DOI: 10.1179/102453309x12583347113537] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
- Shaohua Chen
- Institute of HematologyMedical College, Jinan University, Guangzhou, China
| | - Lijian Yang
- Institute of HematologyMedical College, Jinan University, Guangzhou, China
| | - Xiaoye Lu
- Department of Histology and EmbryologyMedical College, Jinan University, Guangzhou, China
| | - Bo Li
- Institute of HematologyMedical College, Jinan University, Guangzhou, China
| | - John Yeuk-Hon Chan
- Key Laboratory for Regenerative Medicine of Ministry of EducationJinan University, Guangzhou, China
| | - Dongqing Cai
- Key Laboratory for Regenerative Medicine of Ministry of EducationJinan University, Guangzhou, China
| | - Yangqiu Li
- Institute of HematologyMedical College, Jinan University, Guangzhou, China; Key Laboratory for Regenerative Medicine of Ministry of Education, Jinan University, Guangzhou, China
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Sun H, Chu H, Fu T, Shen H, Li G. Theoretical elucidation of the origin for assembly of the DAP12 dimer with only one NKG2C in the lipid membrane. J Phys Chem B 2013; 117:4789-97. [PMID: 23560746 DOI: 10.1021/jp312375g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work, we have investigated in details the origin of the assembly of the DAP12 dimer with only one NKG2C in the activating immunoreceptor complex from thew two aspects of electronic properties and dynamic structures by performing density functional theory (DFT) calculations and molecular dynamics (MD) simulations. In the DFT calculations, we studied the aggregation ability of the NKG2C(TM) with the DAP12(TM) dimer and the DAP12(TM)-DAP12(TM)-NKG2C(TM) complex by analyzing the electrostatic potentials and frontier molecular orbitals (FMOs), and in the MD simulations we mainly investigated the dynamic structures of the DAP12(TM)-DAP12(TM)-NKG2C(TM) complex and its mutants, as well as the tetramer complex consisting of two DAP12(TM) and two NKG2C(TM) helixes without any restriction. Through the studies of the electrostatic potential, the FMOs, and the dynamic structures, we have provided reasonable explanations to some extent for the experimental observation that only one NKG2C can associate with the DAP12 homodimer. The present theoretical results are expected to give valuable information for further studying the assembly between receptors and signaling subunits.
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Affiliation(s)
- Hui Sun
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Rd., Dalian, 116023, PR China
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40
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Kuhns MS, Badgandi HB. Piecing together the family portrait of TCR-CD3 complexes. Immunol Rev 2013; 250:120-43. [PMID: 23046126 DOI: 10.1111/imr.12000] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The pre-T-cell receptor (TCR)-, αβTCR-, and γδTCR-CD3 complexes are members of a family of modular biosensors that are responsible for driving T-cell development, activation, and effector functions. They inform essential checkpoint decisions by relaying key information from their ligand-binding modules (TCRs) to their signaling modules (CD3γε + CD3δε and CD3ζζ) and on to the intracellular signaling apparatus. Their actions shape the T-cell repertoire, as well as T-cell-mediated immunity; yet, the mechanisms that underlie their activity remain an enigma. As with any molecular machine, understanding how they function depends upon understanding how their parts fit and work together. In the 30 years since the initial biochemical and genetic characterizations of the αβTCR, the structure and function of the individual components of these family members have been extensively characterized. Cumulatively, this information has allowed us to piece together a portrait of the αβTCR-CD3 complex and outline the form of the remaining family members. Here we review the known structural and functional characteristics of the components of these TCR-CD3 complex family members. We then discuss how these data have informed our understanding of the architecture of the αβTCR-CD3 complex as well as their implications for the other family members. The intent is to provide a framework for considering: (i) how these thematically similar complexes diverge to execute their specific functions and (ii) how our knowledge of the form and function of these distinct family members can cross-inform our understanding of the other family members.
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Affiliation(s)
- Michael S Kuhns
- Department of Immunobiology, The University of Arizona College of Medicine, Tucson, USA.
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41
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Sharma S, Juffer AH. An atomistic model for assembly of transmembrane domain of T cell receptor complex. J Am Chem Soc 2013; 135:2188-97. [PMID: 23320396 DOI: 10.1021/ja308413e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The T cell receptor (TCR) together with accessory cluster of differentiation 3 (CD3) molecules (TCR-CD3 complex) is a key component in the primary function of T cells. The nature of association of the transmembrane domains is of central importance to the assembly of the complex and is largely unknown. Using multiscale molecular modeling and simulations, we have investigated the structure and assembly of the TCRα-CD3ε-CD3δ transmembrane domains both in membrane and in micelle environments. We demonstrate that in a membrane environment the transmembrane basic residue of the TCR closely interacts with both of the transmembrane acidic residues of the CD3 dimer. In contrast, in a micelle the basic residue interacts with only one of the acidic residues. Simulations of a recent micellar nuclear magnetic resonance structure of the natural killer (NK) cell-activating NKG2C-DAP12-DAP12 trimer in a membrane further indicate that the environment significantly affects the way these trimers associate. Since the currently accepted model for transmembrane association is entirely based on a micellar structure, we propose a revised model for the association of transmembrane domains of the activating immune receptors in a membrane environment.
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Affiliation(s)
- Satyan Sharma
- Biocenter Oulu and Department of Biochemistry, University of Oulu, P.O. Box 3000, Oulu FI-90014, Finland
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42
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Huang L, Chen S, Zha X, Yang L, Li B, Yu Z, Wang L, Li Y. Expression feature of CD3, FcεRIγ, and Zap-70 in patients with chronic lymphocytic leukemia. ACTA ACUST UNITED AC 2012; 17:71-5. [PMID: 22664044 DOI: 10.1179/102453312x13221316477895] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
In leukemia patients, T-cell function has been suppressed with the disease progress. Patients with chronic lymphocytic leukemia (CLL) are all to a degree immunodeficient. In order to elucidate the feature of T-cell receptor signal transduction in CLL, the expression levels of CD3γ, δ, ε, and ζ chain, FcεRIγ, and Zap-70 genes in peripheral blood mononuclear cells (PBMCs) were analyzed. Real-time polymerase chain reaction with SYBR Green technique was used for detecting the gene expression level in PBMCs from 13 patients with CLL, 13 healthy individuals, and 10 B-cell acute lymphocytic leukemia (B-ALL) served as control. The β2-microglobulin gene was used as an endogenous reference. Relative mRNA expression level of genes was analyzed by using the 2(-ΔCt) × 100% method. Significant lower expression levels of CD3γ, ε, and ζ chain genes, as well as FcεRIγ gene were found in CLL samples. Moreover, there was lost the negative correlation of the expression levels between CD3ζ and FcεRIγ genes. The expression level of Zap-70 in CLL was lower than those from healthy controls, while higher than those from B-ALL group. There was no significant correlation between the expression levels of CD3ζ and Zap-70 genes neither in the healthy group nor in the CLL group. In conclusion, the results provide a global gene expression profile of CD3γ, δ, ε, and ζ chains, and the CD3ζ-related genes FcεRIγ and Zap-70 in CLL. Deficiency of these gene expression levels might represent the feature related to T-cell immunodeficiency. The study might contribute to better understand the cellular immune features in CLL patients.
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Affiliation(s)
- Le Huang
- Department of Biomedical Science, Medicine, Nursing and Health Sciences Faculty, Monash University Clayton Campus, Melbourne, Australia
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43
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Zha X, Yan X, Shen Q, Zhang Y, Wu X, Chen S, Li B, Yang L, Geng S, Weng J, Du X, Li Y. Alternative expression of TCRζ related genes in patients with chronic myeloid leukemia. J Hematol Oncol 2012; 5:74. [PMID: 23228155 PMCID: PMC3544630 DOI: 10.1186/1756-8722-5-74] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 12/04/2012] [Indexed: 01/01/2023] Open
Abstract
A previous study has demonstrated a significant decrease in the TCRζ gene expression level in chronic myeloid leukemia (CML); thus, we further investigated the expression of TCRζ-regulating factors, the distribution of the TCRζ 3' untranslated region (3'-UTR) splice variants, and the expression level and correlation of the alternative splicing factor/splicing factor 2 (ASF/SF-2), FcεRIγ and ZAP-70 genes. TCRζ 3'-UTR splice variants were identified in peripheral blood mononuclear cells (PBMCs) from 14 healthy individuals, 40 patients with CML and 22 patients with CML in complete remission (CML-CR) by RT-PCR. The expression level of the TCRζ, FcεRIγ, ASF/SF-2 and ZAP-70 genes was analyzed by real-time quantitative PCR. While the expression of TCRζ gene in the CML group was significantly lower than that in the healthy individual and CML-CR groups, a significantly higher expression of the FceRIγ and ASF/SF-2 genes was found in the CML group. Two types of splicing forms were detected in all of the healthy individual CML-CR cases: wild type (WT) TCRζ 3'-UTR and alternatively splieced (AS) TCRζ 3'-UTR which have been alternatively splieced in the WT TCRζ 3'-UTR . However, 35% of the CML cases contained only the wild type TCRζ 3'-UTR isoform. Based on the TCRζ 3'-UTR isoform expression characteristic, we divided the patients with CML into two subgroups: the WT+AS- CML group, containing patients that express only the wild type TCRζ 3'-UTR, and the WT+AS+ CML group, which contained patients that expressed two TCRζ 3'-UTR isoforms. A significantly different ASF/SF-2 and FcεRIγ gene expression pattern was found between the WT+AS- and WT+AS+CML groups. We concluded that defective TCRζ expression may be characterized in the WT+AS-and WT+AS+CML subgroups by the different gene expression pattern. The overexpression of ASF/SF2, which alternatively splices the TCRζ 3'-UTR, is thought to participate in feedback regulation. The characteristics of TCRζ 3'-UTR alternative splicing may be a novel immunological marker for the evaluation of the CML immune status.
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Affiliation(s)
- Xianfeng Zha
- Institute of Hematology, Medical College, Jinan University, Guangzhou, 510632, China
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44
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Affiliation(s)
- Mohamed Lamkanfi
- Department of Biochemistry, Ghent University, Ghent 9000, Belgium
- Department of Medical Protein Research, VIB, Ghent 9000, Belgium;
| | - Vishva M. Dixit
- Department of Physiological Chemistry, Genentech, South San Francisco, California 94080;
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45
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Zha X, Chen S, Yang L, Shi L, Li B, Wu X, Lu Y, Li Y. Upregulated TCRζ enhances interleukin-2 production in T-cells from patients with CML. DNA Cell Biol 2012; 31:1628-35. [PMID: 23057733 DOI: 10.1089/dna.2012.1798] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
T-cell immunodeficiency is a common feature in patients with chronic myeloid leukemia (CML), and deficiency in CD3 levels was detected in T cells from these patients, which may represent a characteristic that is related to a lower T cell activation. In this study, we explored the possibility that forced TCRζ gene expression may upreg-u-late T cell receptor (TCR) signaling activation and reverse interleukin-2 (IL-2) production in T cells from patients with CML. A recombinant eukaryotic vector expressing TCRζ was transfected into T cells by nucleofection. Phosphorylated TCRζ, phosphorylated NF-κB, and the IL-2 level in TCRζ-transfected CD3+T cells that were activated with anti-CD3 and anti-CD28 antibodies were measured by Western blot and enzyme-linked immunosorbent assay (ELISA). Significantly increased TCRζ levels were found in TCRζ-transfected CD3+T cells. After CD3 and CD28 antibody stimulation, a significantly higher phosphorylated TCRζ chain level was demonstrated, and an increased IL-2 production in TCRζ-upregulated T cells was associated with the increased expression of the phosphorylated NF-κB. In conclusion, TCRζ gene transfection could restore TCRζ chain deficiency and enhance IL-2 production in T cells from patients with CML. It is possible that TCRζ chain reconstitution in leukemia-specific, clonally expanded T cells will effectively increase their activation of antileukemia cytotoxicity.
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Affiliation(s)
- Xianfeng Zha
- Institute of Hematology, Medical College, Jinan University, Guangzhou, China
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46
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Rashid A, Housden JEM, Helm BA, Draber P. Fc receptor-γ subunits with both polar or non-polar amino acids at position of T22 are capable of restoring surface expression of the high-affinity IgE receptor and degranulation in γ subunit-deficient rat basophilic leukemia cells. Mol Immunol 2012; 53:270-3. [PMID: 22964482 DOI: 10.1016/j.molimm.2012.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 08/07/2012] [Indexed: 11/30/2022]
Abstract
The high-affinity IgE receptor (FcɛRI) is formed by the IgE-binding α subunit, β subunit and γ subunits homodimer. All three subunits are required for proper expression of the receptor on the plasma membrane of mast cells and basophils. However, the exact molecular mechanism of inter-subunit interactions required for correct expression and function of the FcɛRI complex remains to be identified. A recent study suggested that polar aspartate at position 194 within the transmembrane domain of the α subunit could interact by hydrogen bonding with polar threonine at position 22 in the transmembrane domains of the γ subunits. To verify this, we used previously isolated rat basophilic leukemia (RBL)-2H3 variant cells deficient in the expression of the FcɛRI-γ subunit (FcR-γ), and transfected them with DNA vectors coding for FcR-γ of the wild-type or mutants in which T22 was substituted for nonpolar alanine (T22A mutant) or polar serine (T22S mutant). Analysis of the transfectants showed that both T22A and T22S mutants were capable to restore surface expression of the FcɛRI similar to wild-type FcR-γ. Furthermore, cells transfected with wild-type, T22A or T22S FcR-γ showed comparably enhanced FcɛRI-mediated degranulation. Our data indicate that substitution of FcR-γ T22 with non-polar amino acid does not interfere with surface expression of the FcɛRI and its signaling capacity.
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Affiliation(s)
- Amir Rashid
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, United Kingdom
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47
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Jaqaman K, Grinstein S. Regulation from within: the cytoskeleton in transmembrane signaling. Trends Cell Biol 2012; 22:515-26. [PMID: 22917551 DOI: 10.1016/j.tcb.2012.07.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/17/2012] [Accepted: 07/17/2012] [Indexed: 12/16/2022]
Abstract
There is mounting evidence that the plasma membrane is highly dynamic and organized in a complex manner. The cortical cytoskeleton is proving to be a particularly important regulator of plasmalemmal organization, modulating the mobility of proteins and lipids in the membrane, facilitating their segregation, and influencing their clustering. This organization plays a critical role in receptor-mediated signaling, especially in the case of immunoreceptors, which require lateral clustering for their activation. Based on recent developments, we discuss the structures and mechanisms whereby the cortical cytoskeleton regulates membrane dynamics and organization, and how the nonuniform distribution of immunoreceptors and their self-association may affect activation and signaling.
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Affiliation(s)
- Khuloud Jaqaman
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
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48
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[Predictive value of intraepithelial (CD3) T-lymphocyte infiltration in resected colorectal cancer]. GASTROENTEROLOGIA Y HEPATOLOGIA 2012; 35:541-50. [PMID: 22858112 DOI: 10.1016/j.gastrohep.2012.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/05/2012] [Accepted: 05/09/2012] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Colorectal cancer (CRC) can induce an anti-tumoral immune response mediated by T-lymphocytes, which express CD3. OBJECTIVES To analyze the prognostic value of tissue expression of intraepithelial CD3 (CD3I) both overall and in the early tumoral stages. METHODS We revised 251 patients with resected CRC and favorable clinical course. CD3I expression was analyzed by immunohistochemistry. Multivariate analysis was used to analyze the variables independently associated with survival. We analyzed CD3I(+) expression in relation to survival and tumoral progression, both overall and in patients with pTNM(I-II) stage tumors. The sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of CD3I expression were analyzed. RESULTS A total of 25.9% of patients with CRC were CD3I(+). After a mean follow-up of 74 months, CD3I(+) expression showed a favorable prognostic value for survival in the multivariate analysis (p=0.045). Survival curves and absence of tumoral progression were more favorable in CD3I(+) cases, both overall (p=0.009 and p=0.004, respectively), and in stages I-II (p=0.029 and p=0.015). The specificity and positive predictive value of CD3I(+) were as follows: Survival: overall: specificity =0.89; positive predictive value =0.91. Stage (I-II): specificity =0.94; positive predictive value =0.98. Absence of tumoral progression: overall: specificity=0.89; positive predictive value =0.88. Stage (I-II): specificity =0.92; positive predictive value =0.96. CONCLUSIONS CD3I expression has an favorable independent prognostic value, with statistically significantly higher percentages of survival and absence of tumoral progression. This more favorable outcome is maintained in the less advanced stages (I-II). CD3I expression shows high specificity and positive predictive value.
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49
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Kuhns MS, Davis MM. TCR Signaling Emerges from the Sum of Many Parts. Front Immunol 2012; 3:159. [PMID: 22737151 PMCID: PMC3381686 DOI: 10.3389/fimmu.2012.00159] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Accepted: 05/27/2012] [Indexed: 11/30/2022] Open
Abstract
“How does T cell receptor signaling begin?” Answering this question requires an understanding of how the parts of the molecular machinery that mediates this process fit and work together. Ultimately this molecular architecture must (i) trigger the relay of information from the TCR-pMHC interface to the signaling substrates of the CD3 molecules and (ii) bring the kinases that modify these substrates in close proximity to interact, initiate, and sustain signaling. In this contribution we will discuss advances of the last decade that have increased our understanding of the complex machinery and interactions that underlie this type of signaling.
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Affiliation(s)
- Michael S Kuhns
- Department of Immunobiology, The University of Arizona College of Medicine Tucson, AZ, USA
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50
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Huang J, Meyer C, Zhu C. T cell antigen recognition at the cell membrane. Mol Immunol 2012; 52:155-64. [PMID: 22683645 DOI: 10.1016/j.molimm.2012.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 04/27/2012] [Accepted: 05/01/2012] [Indexed: 11/16/2022]
Abstract
T cell antigen receptors (TCRs) on the surface of T cells bind specifically to particular peptide bound major histocompatibility complexes (pMHCs) presented on the surface of antigen presenting cells (APCs). This interaction is a key event in T cell antigen recognition and activation. Most studies have used surface plasmon resonance (SPR) to measure the in vitro binding kinetics of TCR-pMHC interactions in solution using purified proteins. However, these measurements are not physiologically precise, as both TCRs and pMHCs are membrane-associated molecules which are regulated by their cellular environments. Recently, single-molecule förster resonance energy transfer (FRET) and single-molecule mechanical assays were used to measure the in situ binding kinetics of TCR-pMHC interactions on the surface of live T cells. These studies have provided exciting insights into the biochemical basis of T cell antigen recognition and suggest that TCRs serially engage with a small number of antigens with very fast kinetics in order to maximize TCR signaling and sensitivity.
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Affiliation(s)
- Jun Huang
- Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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