1
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Integrating T cell receptor sequences and transcriptional profiles by clonotype neighbor graph analysis (CoNGA). Nat Biotechnol 2022; 40:54-63. [PMID: 34426704 PMCID: PMC8832949 DOI: 10.1038/s41587-021-00989-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
Links between T cell clonotypes, as defined by T cell receptor (TCR) sequences, and phenotype, as reflected in gene expression (GEX) profiles, surface protein expression and peptide:major histocompatibility complex binding, can reveal functional relationships beyond the features shared by clonally related cells. Here we present clonotype neighbor graph analysis (CoNGA), a graph theoretic approach that identifies correlations between GEX profile and TCR sequence through statistical analysis of GEX and TCR similarity graphs. Using CoNGA, we uncovered associations between TCR sequence and GEX profiles that include a previously undescribed 'natural lymphocyte' population of human circulating CD8+ T cells and a set of TCR sequence determinants of differentiation in thymocytes. These examples show that CoNGA might help elucidate complex relationships between TCR sequence and T cell phenotype in large, heterogeneous, single-cell datasets.
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2
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The EphB6 Receptor: Kinase-Dead but Very Much Alive. Int J Mol Sci 2021; 22:ijms22158211. [PMID: 34360976 PMCID: PMC8347583 DOI: 10.3390/ijms22158211] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/24/2021] [Accepted: 07/27/2021] [Indexed: 01/15/2023] Open
Abstract
The Eph receptor tyrosine kinase member EphB6 is a pseudokinase, and similar to other pseudoenzymes has not attracted an equivalent amount of interest as its enzymatically-active counterparts. However, a greater appreciation for the role pseudoenzymes perform in expanding the repertoire of signals generated by signal transduction systems has fostered more interest in the field. EphB6 acts as a molecular switch that is capable of modulating the signal transduction output of Eph receptor clusters. Although the biological effects of EphB6 activity are well defined, the molecular mechanisms of EphB6 function remain enigmatic. In this review, we use a comparative approach to postulate how EphB6 acts as a scaffold to recruit adaptor proteins to an Eph receptor cluster and how this function is regulated. We suggest that the evolutionary repurposing of EphB6 into a kinase-independent molecular switch in mammals has involved repurposing the kinase activation loop into an SH3 domain-binding site. In addition, we suggest that EphB6 employs the same SAM domain linker and juxtamembrane domain allosteric regulatory mechanisms that are used in kinase-positive Eph receptors to regulate its scaffold function. As a result, although kinase-dead, EphB6 remains a strategically active component of Eph receptor signaling.
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3
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Wu T, Wang Y, Shi W, Zhang BQ, Raelson J, Yao YM, Wu HD, Xu ZX, Marois-Blanchet FC, Ledoux J, Blunck R, Sheng JZ, Hu SJ, Luo H, Wu J. A Variant in the Nicotinic Acetylcholine Receptor Alpha 3 Subunit Gene Is Associated With Hypertension Risks in Hypogonadic Patients. Front Genet 2020; 11:539862. [PMID: 33329690 PMCID: PMC7728919 DOI: 10.3389/fgene.2020.539862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 11/10/2020] [Indexed: 12/29/2022] Open
Abstract
Ephb6 gene knockout causes hypertension in castrated mice. EPHB6 controls catecholamine secretion by adrenal gland chromaffin cells (AGCCs) in a testosterone-dependent way. Nicotinic acetylcholine receptor (nAChR) is a ligand-gated Ca2+/Na+ channel, and its opening is the first signaling event leading to catecholamine secretion by AGCCs. There is a possibility that nAChR might be involved in EPHB6 signaling, and thus sequence variants of its subunit genes are associated with hypertension risks. CHRNA3 is the major subunit of nAChR used in human and mouse AGCCs. We conducted a human genetic study to assess the association of CHRNA3 variants with hypertension risks in hypogonadic males. The study cohort included 1,500 hypogonadic Chinese males with (750 patients) or without (750 patients) hypertension. The result revealed that SNV rs3743076 in the fourth intron of CHRNA3 was significantly associated with hypertension risks in the hypogonadic males. We further showed that EPHB6 physically interacted with CHRNA3 in AGCCs, providing a molecular basis for nAChR being in the EPHB6 signaling pathway.
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Affiliation(s)
- Tao Wu
- Institute of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yujia Wang
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.,Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Shi
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Bi-Qi Zhang
- Institute of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - John Raelson
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Yu-Mei Yao
- Department of Cardiology, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Huan-Dong Wu
- Institute of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Zao-Xian Xu
- Institute of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | | | - Jonathan Ledoux
- Montreal Heart Institute, Université de Montréal, Montreal, QC, Canada
| | - Rikard Blunck
- Department of Physics, University of Montreal, Montreal, QC, Canada
| | - Jian-Zhong Sheng
- Department of Pathology and Physiopathology, College of Medicine, Zhejiang University, Hangzhou, China
| | - Shen-Jiang Hu
- Institute of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Hongyu Luo
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Jiangping Wu
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.,Nephrology Service, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
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4
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Darling TK, Lamb TJ. Emerging Roles for Eph Receptors and Ephrin Ligands in Immunity. Front Immunol 2019; 10:1473. [PMID: 31333644 PMCID: PMC6620610 DOI: 10.3389/fimmu.2019.01473] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/13/2019] [Indexed: 12/30/2022] Open
Abstract
Eph receptors are the largest family of receptor tyrosine kinases and mediate a myriad of essential processes in humans from embryonic development to adult tissue homeostasis through interactions with membrane-bound ephrin ligands. The ubiquitous expression of Eph receptors and ephrin ligands among the cellular players of the immune system underscores the importance of these molecules in orchestrating an optimal immune response. This review provides an overview of the various roles of Eph receptors and ephrin ligands in immune cell development, activation, and migration. We also discuss the role of Eph receptors in disease pathogenesis as well as the implications of Eph receptors as future immunotherapy targets. Given the diverse and critical roles of Eph receptors and ephrin ligands throughout the immune system during both resting and activated states, this review aims to highlight the critical yet underappreciated roles of this family of signaling molecules in the immune system.
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Affiliation(s)
- Thayer K Darling
- Immunology and Molecular Pathogenesis Program, Emory University Laney Graduate School, Atlanta, GA, United States.,Department of Pathology, University of Utah, Salt Lake City, UT, United States
| | - Tracey J Lamb
- Department of Pathology, University of Utah, Salt Lake City, UT, United States
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5
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Bhatia S, Oweida A, Lennon S, Darragh LB, Milner D, Phan AV, Mueller AC, Van Court B, Raben D, Serkova NJ, Wang XJ, Jimeno A, Clambey ET, Pasquale EB, Karam SD. Inhibition of EphB4-Ephrin-B2 Signaling Reprograms the Tumor Immune Microenvironment in Head and Neck Cancers. Cancer Res 2019; 79:2722-2735. [PMID: 30894369 PMCID: PMC6522285 DOI: 10.1158/0008-5472.can-18-3257] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/15/2019] [Accepted: 03/14/2019] [Indexed: 12/26/2022]
Abstract
Identifying targets present in the tumor microenvironment that contribute to immune evasion has become an important area of research. In this study, we identified EphB4-ephrin-B2 signaling as a regulator of both innate and adaptive components of the immune system. EphB4 belongs to receptor tyrosine kinase family that interacts with ephrin-B2 ligand at sites of cell-cell contact, resulting in bidirectional signaling. We found that EphB4-ephrin-B2 inhibition alone or in combination with radiation (RT) reduced intratumoral regulatory T cells (Tregs) and increased activation of both CD8+ and CD4+Foxp3- T cells compared with the control group in an orthotopic head and neck squamous cell carcinoma (HNSCC) model. We also compared the effect of EphB4-ephrin-B2 inhibition combined with RT with combined anti-PDL1 and RT and observed similar tumor growth suppression, particularly at early time-points. A patient-derived xenograft model showed reduction of tumor-associated M2 macrophages and favored polarization towards an antitumoral M1 phenotype following EphB4-ephrin-B2 inhibition with RT. In vitro, EphB4 signaling inhibition decreased Ki67-expressing Tregs and Treg activation compared with the control group. Overall, our study is the first to implicate the role of EphB4-ephrin-B2 in tumor immune response. Moreover, our findings suggest that EphB4-ephrin-B2 inhibition combined with RT represents a potential alternative for patients with HNSCC and could be particularly beneficial for patients who are ineligible to receive or cannot tolerate anti-PDL1 therapy. SIGNIFICANCE: These findings present EphB4-ephrin-B2 inhibition as an alternative to anti-PDL1 therapeutics that can be used in combination with radiation to induce an effective antitumor immune response in patients with HNSCC.
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Affiliation(s)
- Shilpa Bhatia
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Ayman Oweida
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Shelby Lennon
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Laurel B Darragh
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Dallin Milner
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Andy V Phan
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Adam C Mueller
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Benjamin Van Court
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - David Raben
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Natalie J Serkova
- Department of Anesthesiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Xiao-Jing Wang
- Department of Pathology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
- Veterans Affairs Medical Center, VA Eastern Colorado Health Care System, Aurora, Colorado
| | - Antonio Jimeno
- Division of Medical Oncology, Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Eric T Clambey
- Department of Anesthesiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Elena B Pasquale
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California
| | - Sana D Karam
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado.
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6
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Shi W, Wang Y, Peng J, Qi S, Vitale N, Kaneda N, Murata T, Luo H, Wu J. EPHB6 controls catecholamine biosynthesis by up-regulating tyrosine hydroxylase transcription in adrenal gland chromaffin cells. J Biol Chem 2019; 294:6871-6887. [PMID: 30824540 DOI: 10.1074/jbc.ra118.005767] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 02/25/2019] [Indexed: 11/06/2022] Open
Abstract
EPHB6 is a member of the erythropoietin-producing hepatocellular kinase (EPH) family and a receptor tyrosine kinase with a dead kinase domain. It is involved in blood pressure regulation and adrenal gland catecholamine (CAT) secretion, but several facets of EPHB6-mediated CAT regulation are unclear. In this study, using biochemical, quantitative RT-PCR, immunoblotting, and gene microarray assays, we found that EPHB6 up-regulates CAT biosynthesis in adrenal gland chromaffin cells (AGCCs). We observed that epinephrine content is reduced in the AGCCs from male Ephb6-KO mice, caused by decreased expression of tyrosine hydroxylase, the rate-limiting enzyme in CAT biosynthesis. We demonstrate that the signaling pathway from EPHB6 to tyrosine hydroxylase expression in AGCCs involves Rac family small GTPase 1 (RAC1), MAP kinase kinase 7 (MKK7), c-Jun N-terminal kinase (JNK), proto-oncogene c-Jun, activator protein 1 (AP1), and early growth response 1 (EGR1). On the other hand, signaling via extracellular signal-regulated kinase (ERK1/2), p38 mitogen-activated protein kinase, and ELK1, ETS transcription factor (ELK1) was not affected by EPHB6 deletion. We further report that EPHB6's effect on AGCCs was via reverse signaling through ephrin B1 and that EPHB6 acted in concert with the nongenomic effect of testosterone to control CAT biosynthesis. Our findings elucidate the mechanisms by which EPHB6 modulates CAT biosynthesis and identify potential therapeutic targets for diseases, such as hypertension, caused by dysfunctional CAT biosynthesis.
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Affiliation(s)
- Wei Shi
- From the Research Centre and
| | - Yujia Wang
- From the Research Centre and.,the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, China
| | | | | | - Nicolas Vitale
- the Institut des Neurosciences Cellulaires et Intégratives, UPR-3212, CNRS-Université de Strasbourg, 5 rue Blaise Pascal, 67000 Strasbourg, France, and
| | - Norio Kaneda
- the Department of Analytical Neurobiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 4688503, Japan
| | - Tomiyasu Murata
- the Department of Analytical Neurobiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 4688503, Japan
| | | | - Jiangping Wu
- From the Research Centre and .,Nephrology Department, Centre Hospitalier de l'Université de Montréal Montreal, Quebec, H2X 0A9, Canada
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7
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Ernst AS, Böhler LI, Hagenston AM, Hoffmann A, Heiland S, Sticht C, Bendszus M, Hecker M, Bading H, Marti HH, Korff T, Kunze R. EphB2-dependent signaling promotes neuronal excitotoxicity and inflammation in the acute phase of ischemic stroke. Acta Neuropathol Commun 2019; 7:15. [PMID: 30722785 PMCID: PMC6362601 DOI: 10.1186/s40478-019-0669-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 01/28/2019] [Indexed: 12/16/2022] Open
Abstract
Local cerebral hypoperfusion causes ischemic stroke while driving multiple cell-specific responses including inflammation, glutamate-induced neurotoxicity mediated via NMDAR, edema formation and angiogenesis. Despite the relevance of these pathophysiological mechanisms for disease progression and outcome, molecular determinants controlling the onset of these processes are only partially understood. In this context, our study intended to investigate the functional role of EphB2, a receptor tyrosine kinase that is crucial for synapse function and binds to membrane-associated ephrin-B ligands. Cerebral ischemia was induced in Ephb2−/− mice by transient middle cerebral artery occlusion followed by different times (6, 12, 24 and 48 h) of reperfusion. Histological, neurofunctional and transcriptome analyses indicated an increase in EphB2 phosphorylation under these conditions and attenuated progression of stroke in Ephb2−/− mice. Moreover, while infiltration of microglia/macrophages and astrocytes into the peri-infarct region was not altered, expression of the pro-inflammatory mediators MCP-1 and IL-6 was decreased in these mice. In vitro analyses indicated that binding of EphB2 to astrocytic ephrin-B ligands stimulates NF-κB-mediated cytokine expression via the MAPK pathway. Further magnetic resonance imaging of the Ephb2−/− ischemic brain revealed a lower level of cytotoxic edema formation within 6 h upon onset of reperfusion. On the mechanistic level, absence of neuronal EphB2 decreased the mitochondrial Ca2+ load upon specific activation of NMDAR but not during synaptic activity. Furthermore, neuron-specific loss of ephrin-B2 reduced the extent of cerebral tissue damage in the acute phase of ischemic stroke. Collectively, EphB2 may promote the immediate response to an ischemia-reperfusion event in the central nervous system by (i) pro-inflammatory activation of astrocytes via ephrin-B-dependent signaling and (ii) amplification of NMDA-evoked neuronal excitotoxicity.
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8
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Wu T, Zhang BQ, Raelson J, Yao YM, Wu HD, Xu ZX, Marois-Blanchet FC, Tahir MR, Wang Y, Bradley WE, Luo H, Wu J, Sheng JZ, Hu SJ. Analysis of the association of EPHB6, EFNB1 and EFNB3 variants with hypertension risks in males with hypogonadism. Sci Rep 2018; 8:14497. [PMID: 30262919 PMCID: PMC6160468 DOI: 10.1038/s41598-018-32836-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 09/14/2018] [Indexed: 12/29/2022] Open
Abstract
Several members of the EPH kinase family and their ligands are involved in blood pressure regulation, and such regulation is often sex- or sex hormone-dependent, based on animal and human genetic studies. EPHB6 gene knockout (KO) in mice leads to hypertension in castrated males but not in un-manipulated KO males or females. To assess whether this finding in mice is relevant to human hypertension, we conducted a human genetic study for the association of EPHB6 and its two ligands, EFNB1 and EFNB3, with hypertension in hypogonadic patients. Seven hundred and fifty hypertensive and 750 normotensive Han Chinese patients, all of whom were hypogonadic, were genotyped for single nucleotide polymorphisms (SNPs) within the regions of the genes, plus an additional 50 kb 5′ of the genes for EPHB6, EFNB1 and EFNB3. An imputed insertion/deletion polymorphism, rs35530071, was found to be associated with hypertension at p-values below the Bonferroni-corrected significance level of 0.0024. This marker is located 5′ upstream of the EFNB3 gene start site. Previous animal studies showed that while male EFNB3 gene knockout mice were normotensive, castration of these mice resulted in hypertension, corroborating the results of the human genetic study. Considering the significant associations of EFNB3 SNPs with hypertension in hypogonadic males and supporting evidence from castrated EFNB3 KO mice, we conclude that loss-of-function variants of molecules in the EPHB6 signaling pathway in the presence of testosterone are protective against hypertension in humans.
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Affiliation(s)
- Tao Wu
- Institute of Cardiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Bi-Qi Zhang
- Institute of Cardiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - John Raelson
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Yu-Mei Yao
- Department of Cardiology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Huan-Dong Wu
- Institute of Cardiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Zao-Xian Xu
- Institute of Cardiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | | | - Muhammad Ramzan Tahir
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Yujia Wang
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada.,Children's Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310003, China
| | - W Edward Bradley
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Hongyu Luo
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Jiangping Wu
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada. .,Nephrology Service, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, H2X 0A9, Canada.
| | - Jian-Zhong Sheng
- Department of Pathology and Physiopathology, College of Medicine, Zhejiang University, Hangzhou, 310005, China.
| | - Shen-Jiang Hu
- Institute of Cardiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
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9
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Lacher MD, Bauer G, Fury B, Graeve S, Fledderman EL, Petrie TD, Coleal-Bergum DP, Hackett T, Perotti NH, Kong YY, Kwok WW, Wagner JP, Wiseman CL, Williams WV. SV-BR-1-GM, a Clinically Effective GM-CSF-Secreting Breast Cancer Cell Line, Expresses an Immune Signature and Directly Activates CD4 + T Lymphocytes. Front Immunol 2018; 9:776. [PMID: 29867922 PMCID: PMC5962696 DOI: 10.3389/fimmu.2018.00776] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 03/28/2018] [Indexed: 12/18/2022] Open
Abstract
Targeted cancer immunotherapy with irradiated, granulocyte–macrophage colony-stimulating factor (GM-CSF)-secreting, allogeneic cancer cell lines has been an effective approach to reduce tumor burden in several patients. It is generally assumed that to be effective, these cell lines need to express immunogenic antigens coexpressed in patient tumor cells, and antigen-presenting cells need to take up such antigens then present them to patient T cells. We have previously reported that, in a phase I pilot study (ClinicalTrials.gov NCT00095862), a subject with stage IV breast cancer experienced substantial regression of breast, lung, and brain lesions following inoculation with clinical formulations of SV-BR-1-GM, a GM-CSF-secreting breast tumor cell line. To identify diagnostic features permitting the prospective identification of patients likely to benefit from SV-BR-1-GM, we conducted a molecular analysis of the SV-BR-1-GM cell line and of patient-derived blood, as well as a tumor specimen. Compared to normal human breast cells, SV-BR-1-GM cells overexpress genes encoding tumor-associated antigens (TAAs) such as PRAME, a cancer/testis antigen. Curiously, despite its presumptive breast epithelial origin, the cell line expresses major histocompatibility complex (MHC) class II genes (HLA-DRA, HLA-DRB3, HLA-DMA, HLA-DMB), in addition to several other factors known to play immunostimulatory roles. These factors include MHC class I components (B2M, HLA-A, HLA-B), ADA (encoding adenosine deaminase), ADGRE5 (CD97), CD58 (LFA3), CD74 (encoding invariant chain and CLIP), CD83, CXCL8 (IL8), CXCL16, HLA-F, IL6, IL18, and KITLG. Moreover, both SV-BR-1-GM cells and the responding study subject carried an HLA-DRB3*02:02 allele, raising the question of whether SV-BR-1-GM cells can directly present endogenous antigens to T cells, thereby inducing a tumor-directed immune response. In support of this, SV-BR-1-GM cells (which also carry the HLA-DRB3*01:01 allele) treated with yellow fever virus (YFV) envelope (Env) 43–59 peptides reactivated YFV-DRB3*01:01-specific CD4+ T cells. Thus, the partial HLA allele match between SV-BR-1-GM and the clinical responder might have enabled patient T lymphocytes to directly recognize SV-BR-1-GM TAAs as presented on SV-BR-1-GM MHCs. Taken together, our findings are consistent with a potentially unique mechanism of action by which SV-BR-1-GM cells can act as APCs for previously primed CD4+ T cells.
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Affiliation(s)
| | - Gerhard Bauer
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Brian Fury
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Sanne Graeve
- BriaCell Therapeutics Corp., Berkeley, CA, United States
| | - Emily L Fledderman
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Tye D Petrie
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Dane P Coleal-Bergum
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Tia Hackett
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Nicholas H Perotti
- GMP Facility, Institute for Regenerative Cures, University of California, Davis (UCD), Sacramento, CA, United States
| | - Ying Y Kong
- Benaroya Research Institute at Virginia Mason, Seattle, WA, United States
| | - William W Kwok
- Benaroya Research Institute at Virginia Mason, Seattle, WA, United States
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10
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Kou CTJ, Kandpal RP. Differential Expression Patterns of Eph Receptors and Ephrin Ligands in Human Cancers. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7390104. [PMID: 29682554 PMCID: PMC5851329 DOI: 10.1155/2018/7390104] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/11/2018] [Accepted: 01/22/2018] [Indexed: 12/20/2022]
Abstract
Eph receptors constitute the largest family of receptor tyrosine kinases, which are activated by ephrin ligands that either are anchored to the membrane or contain a transmembrane domain. These molecules play important roles in the development of multicellular organisms, and the physiological functions of these receptor-ligand pairs have been extensively documented in axon guidance, neuronal development, vascular patterning, and inflammation during tissue injury. The recognition that aberrant regulation and expression of these molecules lead to alterations in proliferative, migratory, and invasive potential of a variety of human cancers has made them potential targets for cancer therapeutics. We present here the involvement of Eph receptors and ephrin ligands in lung carcinoma, breast carcinoma, prostate carcinoma, colorectal carcinoma, glioblastoma, and medulloblastoma. The aberrations in their abundances are described in the context of multiple signaling pathways, and differential expression is suggested as the mechanism underlying tumorigenesis.
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Affiliation(s)
- Chung-Ting Jimmy Kou
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Raj P. Kandpal
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
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11
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Wang Y, Shi W, Blanchette A, Peng J, Qi S, Luo H, Ledoux J, Wu J. EPHB6 and testosterone in concert regulate epinephrine release by adrenal gland chromaffin cells. Sci Rep 2018; 8:842. [PMID: 29339804 PMCID: PMC5770418 DOI: 10.1038/s41598-018-19215-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 12/27/2017] [Indexed: 12/22/2022] Open
Abstract
Erythropoietin-producing human hepatocellular receptor (EPH) B6 (EPHB6) is a member of the receptor tyrosine kinase family. We previously demonstrated that EPHB6 knockout reduces catecholamine secretion in male but not female mice, and castration reverses this phenotype. We showed here that male EPHB6 knockout adrenal gland chromaffin cells presented reduced acetylcholine-triggered Ca2+ influx. Such reduction depended on the non-genomic effect of testosterone. Increased large conductance calcium-activated potassium channel current densities were recorded in adrenal gland chromaffin cells from male EPHB6 knockout mice but not from castrated knockout or female knockout mice. Blocking of the large conductance calcium-activated potassium channel in adrenal gland chromaffin cells from male knockout mice corrected their reduced Ca2+ influx. We conclude that the absence of EPHB6 and the presence of testosterone would lead to augmented large conductance calcium-activated potassium channel currents, which limit voltage-gated calcium channel opening in adrenal gland chromaffin cells. Consequently, acetylcholine-triggered Ca2+ influx is reduced, leading to lower catecholamine release in adrenal gland chromaffin cells from male knockout mice. This explains the reduced resting-state blood catecholamine levels, and hence the blood pressure, in male but not female EPHB6 knock mice. These findings have certain clinical implications.
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Affiliation(s)
- Yujia Wang
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada
- The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310003, China
| | - Wei Shi
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada
| | | | - Junzheng Peng
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Shijie Qi
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada
| | - Hongyu Luo
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada.
| | - Jonathan Ledoux
- Montreal Heart Institute, Montreal, Quebec, H1T 1C8, Canada.
| | - Jiangping Wu
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, H2X 0A9, Canada.
- Nephrology Department, CHUM, Montreal, Quebec, H2L 4M1, Canada.
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12
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Tremblay J, Wang Y, Raelson J, Marois-Blanchet FC, Wu Z, Luo H, Bradley E, Chalmers J, Woodward M, Harrap S, Hamet P, Wu J. Evidence from single nucleotide polymorphism analyses of ADVANCE study demonstrates EFNB3 as a hypertension risk gene. Sci Rep 2017; 7:44114. [PMID: 28272517 PMCID: PMC5341021 DOI: 10.1038/srep44114] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 02/03/2017] [Indexed: 01/11/2023] Open
Abstract
EPH kinases and their ligands, ephrins (EFNs), have vital and diverse biological functions. We recently reported that Efnb3 gene deletion results in hypertension in female but not male mice. These data suggest that EFNB3 regulates blood pressure in a sex- and sex hormone-dependent way. In the present study, we conducted a human genetic study to assess the association of EFNB3 single nucleotide polymorphisms with human hypertension risks, using 3,448 patients with type 2 diabetes from the ADVANCE study (Action in Diabetes and Vascular Disease: Peterax and Diamicron MR Controlled Evaluation). We have observed significant association between 2 SNPs in the 3′ untranslated region or within the adjacent region just 3′ of the EFNB3 gene with hypertension, corroborating our findings from the mouse model. Thus, our investigation has shown that EFNB3 is a hypertension risk gene in certain individuals.
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Affiliation(s)
- Johanne Tremblay
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - Yujia Wang
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - John Raelson
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | | | - Zenghui Wu
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - Hongyu Luo
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - Edward Bradley
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - John Chalmers
- The George Institute for Global Health, University of Sydney Sydney, New South Wales, 2006, Australia
| | - Mark Woodward
- The George Institute for Global Health, University of Sydney Sydney, New South Wales, 2006, Australia.,The George Institute for Global Health, University of Oxford, Oxford, UK
| | - Stephen Harrap
- Department of Epidemiology, Johns Hopkins University, Baltimore MD, USA.,Department of Physiology, University of Melbourne, Victoria 3010, Australia
| | - Pavel Hamet
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
| | - Jiangping Wu
- Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, Canada
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13
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The role of Eph/ephrin molecules in stromal–hematopoietic interactions. Int J Hematol 2016; 103:145-54. [PMID: 26475284 DOI: 10.1007/s12185-015-1886-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 12/12/2022]
Abstract
Bone marrow mesenchymal stromal/stem cells(BMSC) are fundamental regulatory elements of the hematopoietic stem cell niche; however, the molecular signals that mediate BMSC support of hematopoiesis are poorly understood. Recent studies indicate that BMSC and hematopoietic stem/progenitors cells differentially express the Eph cell surface tyrosine kinase receptors, and their ephrinligands. Eph/ephrin interactions are thought to mediate cross-talk between BMSC and different hematopoietic cell populations to influence cell development, migration and function. This review summarizes Eph/ephrin interactions in the regulation of BMSC communication with hematopoietic stem/progenitor cells and discusses Eph/ephrintargeted therapeutic strategies that are currently being pursued or various hematotological malignancies.
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14
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The role of GRIP1 and ephrin B3 in blood pressure control and vascular smooth muscle cell contractility. Sci Rep 2016; 6:38976. [PMID: 27941904 PMCID: PMC5150233 DOI: 10.1038/srep38976] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 11/16/2016] [Indexed: 12/25/2022] Open
Abstract
Several erythropoietin-producing hepatocellular receptor B family (EPHB) and their ligands, ephrinBs (EFNBs), are involved in blood pressure regulation in animal models. We selected 528 single nucleotide polymorphisms (SNPs) within the genes of EPHB6, EFNB2, EFNB3 and GRIP1 in the EPH/EFN signalling system to query the International Blood Pressure Consortium dataset. A SNP within the glutamate receptor interacting protein 1 (GRIP1) gene presented a p-value of 0.000389, approaching the critical p-value of 0.000302, for association with diastolic blood pressure of 60,396 individuals. According to echocardiography, we found that Efnb3 gene knockout mice showed enhanced constriction in the carotid arteries. In vitro studies revealed that in mouse vascular smooth muscle cells, siRNA knockdown of GRIP1, which is in the EFNB3 reverse signalling pathway, resulted in increased contractility of these cells. These data suggest that molecules in the EPHB/EFNB signalling pathways, specifically EFNB3 and GRIP1, are involved blood pressure regulation.
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15
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Shiuan E, Chen J. Eph Receptor Tyrosine Kinases in Tumor Immunity. Cancer Res 2016; 76:6452-6457. [PMID: 27811149 DOI: 10.1158/0008-5472.can-16-1521] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/15/2016] [Accepted: 07/20/2016] [Indexed: 12/11/2022]
Abstract
The family of Eph receptor tyrosine kinases and their ephrin ligands regulate a diverse array of physiologic processes, such as axonal guidance, bone remodeling, and immune cell development and trafficking. Eph/ephrin interactions have also been implicated in various pathologic processes, including inflammation, cancer, and tumor angiogenesis. Because Eph receptors play prominent roles in both the immune system and cancer, they likely impact the tumor immune microenvironment, an area in which Eph receptors remain understudied. Here, we provide the first comprehensive review of Eph receptors in the context of tumor immunity. With the recent rise of cancer immunotherapies as promising therapeutic interventions, further elucidation of the roles of Eph receptors in the tumor immune microenvironment will be critical for understanding and developing novel targets against tumor immune evasion. Cancer Res; 76(22); 6452-7. ©2016 AACR.
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Affiliation(s)
- Eileen Shiuan
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee.,Medical Scientist Training Program, Vanderbilt University, Nashville, Tennessee
| | - Jin Chen
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee. .,Division of Rheumatology and Immunology, Department of Medicine, Vanderbilt University, Nashville, Tennessee.,Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee.,Department of Cell & Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, Tennessee
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16
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Wang Y, Hamet P, Thorin E, Tremblay J, Raelson J, Wu Z, Luo H, Jin W, Lavoie JL, Peng J, Marois-Blanchet FC, Tahir MR, Chalmers J, Woodward M, Harrap S, Qi S, Li CY, Wu J. Reduced blood pressure after smooth muscle EFNB2 deletion and the potential association of EFNB2 mutation with human hypertension risk. Eur J Hum Genet 2016; 24:1817-1825. [PMID: 27530629 DOI: 10.1038/ejhg.2016.105] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 06/04/2016] [Accepted: 07/05/2016] [Indexed: 11/09/2022] Open
Abstract
Ephrin B2 (EFNB2) is a ligand for erythropoietin-producing hepatocellular kinases (EPH), the largest family of receptor tyrosine kinases. It has critical functions in many biological systems, but is not known to regulate blood pressure. We generated mice with a smooth muscle cell (SMC)-specific deletion of EFNB2 and investigated its roles in blood pressure regulation and vascular SMC (VSMC) contractility. Male Efnb2 knockout (KO) mice presented reduced blood pressure, whereas female KO mice had no such reduction. Both forward signaling from EFNB2 to EPHs and reverse signaling from EPHs to EFNB2 were involved in regulating VSMC contractility, with EPHB4 serving as a critical molecule for forward signaling, based on crosslinking studies. We also found that a region from aa 313 to aa 331 in the intracellular tail of EFNB2 was essential for reverse signaling regulating VSMC contractility, based on deletion mutation studies. In a human genetic study, we identified five SNPs in the 3' region of the EFNB2 gene, which were in linkage disequilibrium and were significantly associated with hypertension for male but not female subjects, consistent with our findings in mice. The coding (minor) alleles of these five SNPs were protective in males. We have thus discovered a previously unknown blood pressure-lowering mechanism mediated by EFNB2 and identified EFNB2 as a gene associated with hypertension risk in humans.
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Affiliation(s)
- Yujia Wang
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Pavel Hamet
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Eric Thorin
- Department of Surgery, Université de Montréal and Université Montreal Heart Institute, Montreal, QC, Canada
| | - Johanne Tremblay
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - John Raelson
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.,PGX-Services, Montreal, QC, Canada
| | - Zenghui Wu
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Hongyu Luo
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Wei Jin
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Julie L Lavoie
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.,Department of Kinesiology, University of Montreal, Montreal, QC, Canada
| | - Junzheng Peng
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | | | - Muhammad Ramzan Tahir
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - John Chalmers
- Department of Biostatistics, The George Institute for Global Health, University of Sydney, Sydney, NSW, Australia
| | - Mark Woodward
- Department of Biostatistics, The George Institute for Global Health, University of Sydney, Sydney, NSW, Australia
| | - Stephen Harrap
- Department of Physiology, University of Melbourne, Melbourne, VIC, Australia
| | - Shijie Qi
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Charles Yibin Li
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Jiangping Wu
- Research Centre, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.,Department of Nephrology, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
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17
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Wang Y, Wu Z, Thorin E, Tremblay J, Lavoie JL, Luo H, Peng J, Qi S, Wu T, Chen F, Shen J, Hu S, Wu J. Estrogen and testosterone in concert with EFNB3 regulate vascular smooth muscle cell contractility and blood pressure. Am J Physiol Heart Circ Physiol 2016; 310:H861-72. [PMID: 26851246 DOI: 10.1152/ajpheart.00873.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/02/2016] [Indexed: 12/20/2022]
Abstract
EPH kinases and their ligands, ephrins (EFNs), have vital and diverse biological functions, although their function in blood pressure (BP) control has not been studied in detail. In the present study, we report that Efnb3 gene knockout (KO) led to increased BP in female but not male mice. Vascular smooth muscle cells (VSMCs) were target cells for EFNB3 function in BP regulation. The deletion of EFNB3 augmented contractility of VSMCs from female but not male KO mice, compared with their wild-type (WT) counterparts. Estrogen augmented VSMC contractility while testosterone reduced it in the absence of EFNB3, although these sex hormones had no effect on the contractility of VSMCs from WT mice. The effect of estrogen on KO VSMC contractility was via a nongenomic pathway involving GPER, while that of testosterone was likely via a genomic pathway, according to VSMC contractility assays and GPER knockdown assays. The sex hormone-dependent contraction phenotypes in KO VSMCs were reflected in BP in vivo. Ovariectomy rendered female KO mice normotensive. At the molecular level, EFNB3 KO in VSMCs resulted in reduced myosin light chain kinase phosphorylation, an event enhancing sensitivity to Ca(2+)flux in VSMCs. Our investigation has revealed previously unknown EFNB3 functions in BP regulation and show that EFNB3 might be a hypertension risk gene in certain individuals.
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Affiliation(s)
- Yujia Wang
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Zenghui Wu
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada;
| | - Eric Thorin
- Montreal Heart Institute, Montreal, Quebec, Canada
| | - Johanne Tremblay
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Julie L Lavoie
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada; Département de Kinésiologie, Université de Montréal, Montreal, Quebec, Canada
| | - Hongyu Luo
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Junzheng Peng
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Shijie Qi
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Tao Wu
- Institute of Cardiology, First Affiliated Hospital, Zhejiang University Medical College, Hangzhou, China; and
| | - Fei Chen
- Institute of Cardiology, First Affiliated Hospital, Zhejiang University Medical College, Hangzhou, China; and
| | - Jianzhong Shen
- Institute of Cardiology, First Affiliated Hospital, Zhejiang University Medical College, Hangzhou, China; and
| | - Shenjiang Hu
- Institute of Cardiology, First Affiliated Hospital, Zhejiang University Medical College, Hangzhou, China; and
| | - Jiangping Wu
- Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada; Nephrology Service, CRCHUM, Montreal, Quebec, Canada
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18
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Expression of the Receptor Tyrosine Kinase EphB2 on Dendritic Cells Is Modulated by Toll-Like Receptor Ligation but Is Not Required for T Cell Activation. PLoS One 2015; 10:e0138835. [PMID: 26407069 PMCID: PMC4583388 DOI: 10.1371/journal.pone.0138835] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/03/2015] [Indexed: 12/02/2022] Open
Abstract
The Eph receptor tyrosine kinases interact with their ephrin ligands on adjacent cells to facilitate contact-dependent cell communication. Ephrin B ligands are expressed on T cells and have been suggested to act as co-stimulatory molecules during T cell activation. There are no detailed reports of the expression and modulation of EphB receptors on dendritic cells, the main antigen presenting cells that interact with T cells. Here we show that mouse splenic dendritic cells (DC) and bone-marrow derived DCs (BMDC) express EphB2, a member of the EphB family. EphB2 expression is modulated by ligation of TLR4 and TLR9 and also by interaction with ephrin B ligands. Co-localization of EphB2 with MHC-II is also consistent with a potential role in T cell activation. However, BMDCs derived from EphB2 deficient mice were able to present antigen in the context of MHC-II and produce T cell activating cytokines to the same extent as intact DCs. Collectively our data suggest that EphB2 may contribute to DC responses, but that EphB2 is not required for T cell activation. This result may have arisen because DCs express other members of the EphB receptor family, EphB3, EphB4 and EphB6, all of which can interact with ephrin B ligands, or because EphB2 may be playing a role in another aspect of DC biology such as migration.
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19
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Wang Y, Thorin E, Luo H, Tremblay J, Lavoie JL, Wu Z, Peng J, Qi S, Wu J. EPHB4 Protein Expression in Vascular Smooth Muscle Cells Regulates Their Contractility, and EPHB4 Deletion Leads to Hypotension in Mice. J Biol Chem 2015; 290:14235-44. [PMID: 25903126 DOI: 10.1074/jbc.m114.621615] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Indexed: 11/06/2022] Open
Abstract
EPH kinases are the largest family of receptor tyrosine kinases, and their ligands, ephrins (EFNs), are also cell surface molecules. This work presents evidence that EPHB4 on vascular smooth muscle cells (VSMCs) is involved in blood pressure regulation. We generated gene KO mice with smooth muscle cell-specific deletion of EPHB4. Male KO mice, but not female KO mice, were hypotensive. VSMCs from male KO mice showed reduced contractility when compared with their WT counterparts. Signaling both from EFNBs to EPHB4 (forward signaling) and from EPHB4 to EFNB2 (reverse signaling) modulated VSMC contractility. At the molecular level, the absence of EPHB4 in VSMCs resulted in compromised signaling from Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) to myosin light chain kinase (MLCK) to myosin light chain, the last of which controls the contraction force of motor molecule myosin. Near the cell membrane, an adaptor protein GRIP1, which can associate with EFNB2, was found to be essential in mediating EPHB4-to-EFNB reverse signaling, which regulated VSMC contractility, based on siRNA gene knockdown studies. Our research indicates that EPHB4 plays an essential role in regulating small artery contractility and blood pressure.
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Affiliation(s)
- Yujia Wang
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Eric Thorin
- the Montreal Heart Institute, Montreal, Quebec H1T 1C8
| | - Hongyu Luo
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Johanne Tremblay
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Julie L Lavoie
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, the Département de Kinésiologie, Université de Montréal, Montreal, Quebec H3T 1J4, and
| | - Zenghui Wu
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Junzheng Peng
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Shijie Qi
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9
| | - Jiangping Wu
- From the Research Centre, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec H2X 0A9, the Nephrology Service, CHUM, Montreal, Quebec H2L 4M1, Canada
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20
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Nguyen TM, Arthur A, Hayball JD, Gronthos S. EphB and Ephrin-B interactions mediate human mesenchymal stem cell suppression of activated T-cells. Stem Cells Dev 2013; 22:2751-64. [PMID: 23711177 PMCID: PMC3787464 DOI: 10.1089/scd.2012.0676] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 05/27/2013] [Indexed: 01/13/2023] Open
Abstract
Mesenchymal stromal/stem cells (MSC) express the contact-dependent erythropoietin-producing hepatocellular (Eph) receptor tyrosine kinase family and their cognate ephrin ligands, which are known to regulate thymocyte maturation and selection, T-cell transendothelial migration, activation, co-stimulation, and proliferation. However, the contribution of Eph/ephrin molecules in mediating human MSC suppression of activated T-cells remains to be determined. In the present study, we showed that EphB2 and ephrin-B2 are expressed by ex vivo expanded MSC, while the corresponding ligands, ephrin-B1 and EphB4, respectively, are highly expressed by T-cells. Initial studies demonstrated that EphB2-Fc and ephrin-B2-Fc molecules suppressed T-cell proliferation in allogeneic mixed lymphocyte reaction (MLR) assays compared with human IgG-treated controls. While the addition of a third-party MSC population demonstrated dramatic suppression of T-cell proliferation responses in the MLR, blocking the function of EphB2 or EphB4 receptors using inhibitor binding peptides significantly increased T-cell proliferation. Consistent with these observations, shRNA EphB2 or ephrin-B2 knockdown expression in MSC reduced their ability to inhibit T-cell proliferation. Importantly, the expression of immunosuppressive factors, indoleamine 2, 3-dioxygenase, transforming growth factor-β1, and inducible nitric oxide synthase expressed by MSC, was up-regulated after stimulation with EphB4 and ephrin-B1 in the presence of interferon (IFN)-γ, compared with untreated controls. Conversely, key factors involved in T-cell activation and proliferation, such as interleukin (IL)-2, IFN-γ, tumor necrosis factor-α, and IL-17, were down-regulated by T-cells treated with EphB2 or ephrin-B2 compared with untreated controls. Studies utilizing signaling inhibitors revealed that inhibition of T-cell proliferation is partly mediated through EphB2-induced ephrin-B1 reverse signaling or ephrin-B2-mediated EphB4 forward signaling by activating Src, PI3Kinase, Abl, and JNK kinase pathways, activated by tyrosine phosphorylation. Taken together, these observations suggest that EphB/ephrin-B interactions play an important role in mediating human MSC inhibition of activated T cells.
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MESH Headings
- Cell Proliferation
- Coculture Techniques
- Ephrin-B2/antagonists & inhibitors
- Ephrin-B2/genetics
- Ephrin-B2/metabolism
- Gene Expression Regulation
- Humans
- Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics
- Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism
- Interferon-gamma/metabolism
- Interferon-gamma/pharmacology
- Interleukin-17/genetics
- Interleukin-17/metabolism
- Interleukin-2/genetics
- Interleukin-2/metabolism
- Lymphocyte Activation
- Lymphocyte Culture Test, Mixed
- Mesenchymal Stem Cells/cytology
- Mesenchymal Stem Cells/drug effects
- Mesenchymal Stem Cells/metabolism
- Nitric Oxide Synthase Type II/genetics
- Nitric Oxide Synthase Type II/metabolism
- Phosphorylation
- Primary Cell Culture
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Receptor, EphB2/antagonists & inhibitors
- Receptor, EphB2/genetics
- Receptor, EphB2/metabolism
- Receptor, EphB4/genetics
- Receptor, EphB4/metabolism
- Signal Transduction
- T-Lymphocytes/cytology
- T-Lymphocytes/drug effects
- T-Lymphocytes/metabolism
- Transforming Growth Factor beta1/genetics
- Transforming Growth Factor beta1/metabolism
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Affiliation(s)
- Thao M. Nguyen
- Mesenchymal Stem Cell Laboratory, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
- School of Pharmacy and Medical Sciences and Sansom Institute, University of South Australia, Adelaide, SA, Australia
| | - Agnes Arthur
- Mesenchymal Stem Cell Laboratory, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - John D. Hayball
- School of Pharmacy and Medical Sciences and Sansom Institute, University of South Australia, Adelaide, SA, Australia
| | - Stan Gronthos
- Mesenchymal Stem Cell Laboratory, School of Medical Sciences, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
- Centre for Stem Cell Research and Robinson Institute, School of Medical Sciences, University of Adelaide, Adelaide, SA, Australia
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21
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Luo H, Charpentier T, Wang X, Qi S, Han B, Wu T, Terra R, Lamarre A, Wu J. Efnb1 and Efnb2 proteins regulate thymocyte development, peripheral T cell differentiation, and antiviral immune responses and are essential for interleukin-6 (IL-6) signaling. J Biol Chem 2011; 286:41135-41152. [PMID: 21976681 DOI: 10.1074/jbc.m111.302596] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Erythropoietin-producing hepatocellular kinases (Eph kinases) constitute the largest family of cell membrane receptor tyrosine kinases, and their ligand ephrins are also cell surface molecules. Because of promiscuous interaction between Ephs and ephrins, there is considerable redundancy in this system, reflecting the essential roles of these molecules in the biological system through evolution. In this study, both Efnb1 and Efnb2 were null-mutated in the T cell compartment of mice through loxP-mediated gene deletion. Mice with this double conditional mutation (double KO mice) showed reduced thymus and spleen size and cellularity. There was a significant decrease in the DN4, double positive, and single positive thymocyte subpopulations and mature CD4 and CD8 cells in the periphery. dKO thymocytes and peripheral T cells failed to compete with their WT counterparts in irradiated recipients, and the T cells showed compromised ability of homeostatic expansion. dKO naive T cells were inferior in differentiating into Th1 and Th17 effectors in vitro. The dKO mice showed diminished immune response against LCMV infection. Mechanistic studies revealed that IL-6 signaling in dKO T cells was compromised, in terms of abated induction of STAT3 phosphorylation upon IL-6 stimulation. This defect likely contributed to the observed in vitro and in vivo phenotype in dKO mice. This study revealed novel roles of Efnb1 and Efnb2 in T cell development and function.
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Affiliation(s)
- Hongyu Luo
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada
| | - Tania Charpentier
- Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada
| | - Xuehai Wang
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada
| | - Shijie Qi
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada
| | - Bing Han
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada
| | - Tao Wu
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada; Institute of Cardiology, First Affiliated Hospital, Medical College, Zhejiang University, 310003 Hangzhou, China
| | - Rafik Terra
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada
| | - Alain Lamarre
- Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada
| | - Jiangping Wu
- Laboratoire Immunologie, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada; Service Nephrologie, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital, Montreal, Quebec H2L 4M1, Canada.
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EphB-ephrin-B2 interactions are required for thymus migration during organogenesis. Proc Natl Acad Sci U S A 2010; 107:13414-9. [PMID: 20616004 DOI: 10.1073/pnas.1003747107] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Thymus organogenesis requires coordinated interactions of multiple cell types, including neural crest (NC) cells, to orchestrate the formation, separation, and subsequent migration of the developing thymus from the third pharyngeal pouch to the thoracic cavity. The molecular mechanisms driving these processes are unclear; however, NC-derived mesenchyme has been shown to play an important role. Here, we show that, in the absence of ephrin-B2 expression on thymic NC-derived mesenchyme, the thymus remains in the cervical area instead of migrating into the thoracic cavity. Analysis of individual NC-derived thymic mesenchymal cells shows that, in the absence of ephrin-B2, their motility is impaired as a result of defective EphB receptor signaling. This implies a NC-derived cell-specific role of EphB-ephrin-B2 interactions in the collective migration of the thymic rudiment during organogenesis.
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Dodeller F, Schulze-Koops H. The p38 mitogen-activated protein kinase signaling cascade in CD4 T cells. Arthritis Res Ther 2006; 8:205. [PMID: 16542479 PMCID: PMC1526596 DOI: 10.1186/ar1905] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Since the identification of the p38 mitogen-activated protein kinase (MAPK) as a key signal-transducing molecule in the expression of the proinflammatory cytokine tumor necrosis factor (TNF) more than 10 years ago, huge efforts have been made to develop inhibitors of p38 MAPK with the intent to modulate unwanted TNF activity in diseases such as autoimmune diseases or sepsis. However, despite some anti-inflammatory effects in animal models, no p38 MAPK inhibitor has yet demonstrated clinical efficacy in human autoimmune disorders. One possible reason for this paradox might relate to the fact that the p38 MAPK signaling cascade is involved in the functional regulation of several different cell types that all contribute to the complex pathogenesis of human autoimmune diseases. In particular, p38 MAPK has a multifaceted role in CD4 T cells that have been implicated in initiating and driving sustained inflammation in autoimmune diseases, such as rheumatoid arthritis or systemic vasculitis. Here we review recent advances in the understanding of the role of the p38 MAPK signaling cascade in CD4 T cells and the consequences that its inhibition provokes in T cell functions in vitro and in vivo. These new data suggest that p38 MAPK inhibitors may elicit several unwanted effects in human autoimmune diseases but may be useful for the treatment of allergic disorders.
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Affiliation(s)
- Francis Dodeller
- Nikolaus Fiebiger Center for Molecular Medicine, Clinical Research Group III, and Department of Internal Medicine III, University of Erlangen-Nuremberg, Glueckstrasse 6, 91054 Erlangen, Germany
| | - Hendrik Schulze-Koops
- Nikolaus Fiebiger Center for Molecular Medicine, Clinical Research Group III, and Department of Internal Medicine III, University of Erlangen-Nuremberg, Glueckstrasse 6, 91054 Erlangen, Germany
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24
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Luo H, Yu G, Tremblay J, Wu J. EphB6-null mutation results in compromised T cell function. J Clin Invest 2005; 114:1762-73. [PMID: 15599401 PMCID: PMC535066 DOI: 10.1172/jci21846] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2004] [Accepted: 10/05/2004] [Indexed: 11/17/2022] Open
Abstract
So far, there is very limited knowledge about the role of Eph kinases, the largest family of receptor tyrosine kinases, in the immune system. Here, using EphB6(-/-) mice, we demonstrated that in vitro and in vivo T cell responses such as lymphokine secretion, proliferation, and the development of delayed-type skin hypersensitivity and experimental autoimmune encephalitis in EphB6(-/-) mice were compromised. On the other hand, humoral immune responses, such as serum levels of different Ig isotypes and IgG response to tetanus toxoid, were normal in these mice. Mechanistically, we showed that EphB6 migrated to the aggregated TCRs and rafts after TCR activation. Further downstream, in the absence of EphB6, ZAP-70 activation, LAT phosphorylation, the association of PLCgamma1 with SLP-76, and p44/42 MAPK activation were diminished. Thus, we have shown that EphB6 is pivotal in T cell function.
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MESH Headings
- Animals
- Antigens/metabolism
- Antigens, CD/biosynthesis
- Antigens, Differentiation, T-Lymphocyte/biosynthesis
- Biotinylation
- CD28 Antigens/biosynthesis
- CD3 Complex/biosynthesis
- Cell Proliferation
- Cytokines/biosynthesis
- Dose-Response Relationship, Drug
- Exons
- Female
- Flow Cytometry
- Gene Deletion
- Green Fluorescent Proteins/metabolism
- Immunoglobulin Class Switching
- Lectins, C-Type
- Leukocytes/metabolism
- Ligands
- Lymphocytes/metabolism
- Mice
- Mice, Knockout
- Mice, Transgenic
- Microscopy, Confocal
- Models, Genetic
- Mutation
- Polymerase Chain Reaction
- Receptor, EphB6/genetics
- Receptor, EphB6/metabolism
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Interleukin-2/biosynthesis
- Signal Transduction
- Spleen/metabolism
- T-Lymphocytes/metabolism
- Thymus Gland/metabolism
- Time Factors
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Affiliation(s)
- Hongyu Luo
- Laboratory of Immunology, Centre de Recherché, Notre Dame Hospital, Centre Hospitalier de l'Université de Montréal, Pavilion DeSève, 1560 Sherbrooke Street East, Montréal, Quebec H2L 4M1, Canada
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25
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Sobel RA. Ephrin A receptors and ligands in lesions and normal-appearing white matter in multiple sclerosis. Brain Pathol 2005; 15:35-45. [PMID: 15779235 PMCID: PMC8095972 DOI: 10.1111/j.1750-3639.2005.tb00098.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Complexes of the tyrosine kinase ephrin ligands (ephrins) and their receptors (Ephs) provide critical cell recognition signals in CNS development. Complementary ephrin/Eph expression gradients present topographic guidance cues that may either stimulate or repulse axon growth. Some ephrin/Ephs are upregulated in adult CNS injury models. To assess their involvement in multiple sclerosis (MS), ephrin A1-5 and Eph A1-8 expression was analyzed in CNS tissues using immunohistochemistry. Control samples showed distinct expression patterns for each ephrin/Eph on different cell types. Perivascular mononuclear inflammatory cells, reactive astrocytes and macrophages expressed ephrin A1-4, Eph A1, -A3, -A4, -A6 and -A7 in active MS lesions. Axonal ephrin A1 and Eph A3, -A4, and -A7 expression was increased in active lesions and was greater in normal-appearing white matter (NAWM) adjacent to active lesions than within or adjacent to chronic MS lesions, in contralateral NAWM, or in control samples. As in development, therefore, there are temporally dynamic, lesion-associated axonal ephrin/Eph A expression gradients in the CNS of MS patients. These results indicate that ephrin/Eph As are useful cell markers in human CNS tissue samples; they likely are involved in the immunopathogenesis of active lesions and in neurodegeneration in MS NAWM; and they represent potential therapeutic targets in MS.
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Affiliation(s)
- Raymond A Sobel
- Laboratory Service, Veterans Affairs Health Care System, Palo Alto, California 94304, USA.
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Munthe E, Finne EF, Aasheim HC. Expression and functional effects of Eph receptor tyrosine kinase A family members on Langerhans like dendritic cells. BMC Immunol 2004; 5:9. [PMID: 15176971 PMCID: PMC443508 DOI: 10.1186/1471-2172-5-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2003] [Accepted: 06/03/2004] [Indexed: 11/10/2022] Open
Abstract
Background The Eph receptors are the largest receptor tyrosine kinase family. Several family members are expressed in hematopoietic cells. Previously, the expression of a member of this family, EphA2, was identified on dendritic like cells in tonsils. We therefore specifically examined the expression of EphA2 on in vitro generated dendritic cells. Results In this study, expression of the EphA2 receptor was identified on in vitro generated Langerhans like dendritic cells compared to in vitro generated dendritic cells. We show that ligand induced engagement of the EphA2 receptor leads to receptor autophosphorylation indicating a functional receptor signaling pathway in these cells. We also observe phosphorylation and dephosphorylation of distinct proteins following ligand activation of EphA receptors. In co-stimulation assays, receptor-ligand interaction reduces the capacity of the Langerhans like dendritic cells to stimulate resting CD4+ T cells. Conclusion Engagement of EphA receptor tyrosine kinases on Langerhans like dendritic cells induces signaling as shown by tyrosine phosphorylation and dephosphorylation of distinct proteins. Furthermore this engagement renders the cells less capable of stimulating CD4+ T cells.
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Affiliation(s)
- Else Munthe
- Department of Immunology, The Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway
| | - Eivind Farmen Finne
- Department of Immunology, The Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway
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