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Umene K, Kawahara M. Synthetic receptor scaffolds significantly affect the efficiency of cell fate signals. Sci Rep 2024; 14:5801. [PMID: 38461201 PMCID: PMC10925030 DOI: 10.1038/s41598-024-56612-2] [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: 12/12/2023] [Accepted: 03/08/2024] [Indexed: 03/11/2024] Open
Abstract
Mimicry of receptor functions by designing synthetic receptors would be one of the recently hot research trends in cell engineering. While several types of synthetic receptors have been designed to induce desired cell fates in response to external stimuli, little is known about which receptor type signals more efficiently for inducing a certain cell fate. In this study, we compared the performance of three types of synthetic receptor scaffolds, i.e. myristoylated, cytosolic, and transmembrane types that signal through JAK-dependent phosphorylation of tyrosine motifs to transduce growth signaling. As a result, the phosphorylation levels of JAK and subsequent downstream signaling molecules were significantly maintained in the cytosolic type receptors, leading to more efficient cell growth than the other types. In contrast, the phosphorylation levels of JAK decreased in a motif-dependent manner in the transmembrane type receptors. Although various studies on receptor engineering based on domain or motif engineering have been reported, to our knowledge this study is the first to demonstrate that synthetic receptor scaffolds significantly affect the efficiency of cell fate signals. These findings are important for both receptor biology and receptor engineering, providing guidelines for rationally designing synthetic receptors that can transduce as efficient signaling as possible.
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Affiliation(s)
- Kirato Umene
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, 113-8656, Japan
| | - Masahiro Kawahara
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, 113-8656, Japan.
- Laboratory of Cell Vaccine, Microbial Research Center for Health and Medicine (MRCHM), National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki-Shi, Osaka, 567-0085, Japan.
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2
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Urbančič I, Schiffelers L, Jenkins E, Gong W, Santos AM, Schneider F, O'Brien-Ball C, Vuong MT, Ashman N, Sezgin E, Eggeling C. Aggregation and mobility of membrane proteins interplay with local lipid order in the plasma membrane of T cells. FEBS Lett 2021; 595:2127-2146. [PMID: 34160065 DOI: 10.1002/1873-3468.14153] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/07/2021] [Accepted: 06/18/2021] [Indexed: 01/17/2023]
Abstract
To disentangle the elusive lipid-protein interactions in T-cell activation, we investigate how externally imposed variations in mobility of key membrane proteins (T-cell receptor [TCR], kinase Lck, and phosphatase CD45) affect the local lipid order and protein colocalisation. Using spectral imaging with polarity-sensitive membrane probes in model membranes and live Jurkat T cells, we find that partial immobilisation of proteins (including TCR) by aggregation or ligand binding changes their preference towards a more ordered lipid environment, which can recruit Lck. Our data suggest that the cellular membrane is poised to modulate the frequency of protein encounters upon alterations of their mobility, for example in ligand binding, which offers new mechanistic insight into the involvement of lipid-mediated interactions in membrane-hosted signalling events.
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Affiliation(s)
- Iztok Urbančič
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
- Jožef Stefan Institute, Ljubljana, Slovenia
| | - Lisa Schiffelers
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Edward Jenkins
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Weijian Gong
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Ana Mafalda Santos
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Falk Schneider
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | | | - Mai Tuyet Vuong
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Nicole Ashman
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
| | - Erdinc Sezgin
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
- Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Christian Eggeling
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, UK
- Institute of Applied Optics and Biophysics, Friedrich-Schiller-University Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Jena, Germany
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3
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Wu L, Gao A, Lei Y, Li J, Mai K, Ye J. SHP1 tyrosine phosphatase gets involved in host defense against Streptococcus agalactiae infection and BCR signaling pathway in Nile tilapia (Oreochromis niloticus). FISH & SHELLFISH IMMUNOLOGY 2020; 99:562-571. [PMID: 32109611 DOI: 10.1016/j.fsi.2020.02.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/10/2020] [Accepted: 02/14/2020] [Indexed: 06/10/2023]
Abstract
Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1), a kind of protein tyrosine phosphatases (PTPs), is a critical regulator of antigen receptor signal transduction. Signal transduction of BCR is regulated by phosphatases in teleost as in mammals. In this study, SHP1 from Nile tilapia (Oreochromis niloticus) (OnSHP1) was identified and characterized, including the expression pattern against bacterial infection and regulation function in BCR signaling pathway. The open reading frame of OnSHP1 contains 1749 bp of nucleotide sequence, encoding a protein of 582 amino acids. The OnSHP1 protein was highly conversed compared to that of other species, including two amino-terminal SH2 domains at the N terminus and a PTP catalytic domain. Transcriptional expression analysis revealed that OnSHP1 was detected in all examined tissues and highly expressed in spleen. The up-regulated OnSHP1 expression was observed in peripheral blood, spleen and anterior kidney following challenge with Streptococcus agalactiae or lipopolysaccharide (LPS) in vivo, as well as that displayed in leukocytes stimulated with S. agalactiae or LPS in vitro. Further, after induction with mouse anti-tilapia IgM monoclonal antibody in vitro, OnSHP1 was significantly up-regulated in leukocytes. When spleen leukocytes treated with PTP Inhibitor II in vitro, the phosphorylation level of OnSHP1 at the phosphorylation sites (Y535 and Y557) and the cytoplasmic free Ca2+ concentration were up-regulated significantly. Overall, the findings of this study indicate that SHP1 gets involved in host defense against bacterial infection and BCR signaling pathway in Nile tilapia.
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Affiliation(s)
- Liting Wu
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou, 510631, PR China
| | - Along Gao
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou, 510631, PR China
| | - Yang Lei
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou, 510631, PR China
| | - Jun Li
- School of Biological Sciences, Lake Superior State University, Sault Ste. Marie, MI, 49783, USA
| | - Kangsen Mai
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou, 510631, PR China
| | - Jianmin Ye
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangzhou, 510631, PR China.
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Beyond the Cell Surface: Targeting Intracellular Negative Regulators to Enhance T cell Anti-Tumor Activity. Int J Mol Sci 2019; 20:ijms20235821. [PMID: 31756921 PMCID: PMC6929154 DOI: 10.3390/ijms20235821] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 02/07/2023] Open
Abstract
It is well established that extracellular proteins that negatively regulate T cell function, such as Cytotoxic T-Lymphocyte-Associated protein 4 (CTLA-4) and Programmed Cell Death protein 1 (PD-1), can be effectively targeted to enhance cancer immunotherapies and Chimeric Antigen Receptor T cells (CAR-T cells). Intracellular proteins that inhibit T cell receptor (TCR) signal transduction, though less well studied, are also potentially useful therapeutic targets to enhance T cell activity against tumor. Four major classes of enzymes that attenuate TCR signaling include E3 ubiquitin kinases such as the Casitas B-lineage lymphoma proteins (Cbl-b and c-Cbl), and Itchy (Itch), inhibitory tyrosine phosphatases, such as Src homology region 2 domain-containing phosphatases (SHP-1 and SHP-2), inhibitory protein kinases, such as C-terminal Src kinase (Csk), and inhibitory lipid kinases such as Src homology 2 (SH2) domain-containing inositol polyphosphate 5-phosphatase (SHIP) and Diacylglycerol kinases (DGKs). This review describes the mechanism of action of eighteen intracellular inhibitory regulatory proteins in T cells within these four classes, and assesses their potential value as clinical targets to enhance the anti-tumor activity of endogenous T cells and CAR-T cells.
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Saveanu L, Zucchetti AE, Evnouchidou I, Ardouin L, Hivroz C. Is there a place and role for endocyticTCRsignaling? Immunol Rev 2019; 291:57-74. [DOI: 10.1111/imr.12764] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 04/02/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Loredana Saveanu
- National French Institute of Health and Medical Research (INSERM) 1149 Center of Research on Inflammation Paris France
- National French Center of Scientific Research (CNRS) ERL8252 Paris France
- Laboratory of Inflamex Excellency Faculty of Medicine Xavier Bichat Site Paris France
- Paris Diderot UniversitySorbonne Paris Cité Paris France
| | - Andres E. Zucchetti
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
| | - Irini Evnouchidou
- National French Institute of Health and Medical Research (INSERM) 1149 Center of Research on Inflammation Paris France
- National French Center of Scientific Research (CNRS) ERL8252 Paris France
- Laboratory of Inflamex Excellency Faculty of Medicine Xavier Bichat Site Paris France
- Paris Diderot UniversitySorbonne Paris Cité Paris France
- Inovarion Paris France
| | - Laurence Ardouin
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
| | - Claire Hivroz
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
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Gerth E, Mattner J. The Role of Adaptor Proteins in the Biology of Natural Killer T (NKT) Cells. Front Immunol 2019; 10:1449. [PMID: 31293596 PMCID: PMC6603179 DOI: 10.3389/fimmu.2019.01449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 06/10/2019] [Indexed: 12/31/2022] Open
Abstract
Adaptor proteins contribute to the selection, differentiation and activation of natural killer T (NKT) cells, an innate(-like) lymphocyte population endowed with powerful immunomodulatory properties. Distinct from conventional T lymphocytes NKT cells preferentially home to the liver, undergo a thymic maturation and differentiation process and recognize glycolipid antigens presented by the MHC class I-like molecule CD1d on antigen presenting cells. NKT cells express a semi-invariant T cell receptor (TCR), which combines the Vα14-Jα18 chain with a Vβ2, Vβ7, or Vβ8 chain in mice and the Vα24 chain with the Vβ11 chain in humans. The avidity of interactions between their TCR, the presented glycolipid antigen and CD1d govern the selection and differentiation of NKT cells. Compared to TCR ligation on conventional T cells engagement of the NKT cell TCR delivers substantially stronger signals, which trigger the unique NKT cell developmental program. Furthermore, NKT cells express a panoply of primarily inhibitory NK cell receptors (NKRs) that control their self-reactivity and avoid autoimmune activation. Adaptor proteins influence NKT cell biology through the integration of TCR, NKR and/or SLAM (signaling lymphocyte-activation molecule) receptor signals or the variation of CD1d-restricted antigen presentation. TCR and NKR ligation engage the SH2 domain-containing leukocyte protein of 76kDa slp-76 whereas the SLAM associated protein SAP serves as adaptor for the SLAM receptor family. Indeed, the selection and differentiation of NKT cells selectively requires co-stimulation via SLAM receptors. Furthermore, SAP deficiency causes X-linked lymphoproliferative disease with multiple immune defects including a lack of circulating NKT cells. While a deletion of slp-76 leads to a complete loss of all peripheral T cell populations, mutations in the SH2 domain of slp-76 selectively affect NKT cell biology. Furthermore, adaptor proteins influence the expression and trafficking of CD1d in antigen presenting cells and subsequently selection and activation of NKT cells. Adaptor protein complex 3 (AP-3), for example, is required for the efficient presentation of glycolipid antigens which require internalization and processing. Thus, our review will focus on the complex contribution of adaptor proteins to the delivery of TCR, NKR and SLAM receptor signals in the unique biology of NKT cells and CD1d-restricted antigen presentation.
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Affiliation(s)
- Evelyn Gerth
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Jochen Mattner
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen, Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
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7
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HoxA10 Facilitates SHP-1-Catalyzed Dephosphorylation of p38 MAPK/STAT3 To Repress Hepatitis B Virus Replication by a Feedback Regulatory Mechanism. J Virol 2019; 93:JVI.01607-18. [PMID: 30674631 DOI: 10.1128/jvi.01607-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 01/17/2019] [Indexed: 02/07/2023] Open
Abstract
Hepatitis B virus (HBV) infection is the leading cause of chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). This study reveals a distinct mechanism underlying the regulation of HBV replication. HBV activates homeobox A10 (HoxA10) in human hepatocytes, leukocytes, peripheral blood mononuclear cells (PBMCs), HepG2-NTCP cells, leukocytes isolated from CHB patients, and HBV-associated HCC tissues. HoxA10 in turn represses HBV replication in human hepatocytes, HepG2-NTCP cells, and BALB/c mice. Interestingly, we show that during early HBV infection, p38 mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) were activated to facilitate HBV replication; however, during late HBV infection, HoxA10 was induced to attenuate HBV replication. Detailed studies reveal that HoxA10 binds to p38 MAPK, recruits SH2-containing protein tyrosine phosphatase 1 (SHP-1) to facilitate SHP-1 in catalyzing dephosphorylation of p38 MAPK/STAT3, and thereby attenuates p38 MAPK/STAT3 activation and HBV replication. Furthermore, HoxA10 binds to the HBV enhancer element I (EnhI)/X promoter, competes with STAT3 for binding of the promoter, and thereby represses HBV transcription. Taken together, these results show that HoxA10 attenuates HBV replication through repressing the p38 MAPK/STAT3 pathway by two approaches: HoxA10 interacts with p38 MAPK and recruits SHP-1 to repress HBV replication, and HoxA10 binds to the EnhI/X promoter and competes with STAT3 to attenuate HBV transcription. Thus, the function of HoxA10 is similar to the action of interferon (IFN) in terms of inhibition of HBV infection; however, the mechanism of HoxA10-mediated repression of HBV replication is different from the mechanism underlying IFN-induced inhibition of HBV infection.IMPORTANCE Two billion people have been infected with HBV worldwide; about 240 million infected patients developed chronic hepatitis B (CHB), and 650,000 die each year from liver cirrhosis (LC) or hepatocellular carcinoma (HCC). This work elucidates a mechanism underlying the control of HBV replication. HBV infection activates HoxA10, a regulator of cell differentiation and cancer progression, in human cells and patients with CHB and HCC. HoxA10 subsequently inhibits HBV replication in human tissue culture cells and mice. Additionally, HoxA10 interacts with p38 MAPK to repress the activation of p38 MAPK and STAT3 and recruits and facilitates SHP-1 to catalyze the dephosphorylation of p38 MAPK and STAT3. Moreover, HoxA10 competes with STAT3 for binding of the HBV X promoter to repress HBV transcription. Thus, this work reveals a negative regulatory mechanism underlying the control of HBV replication and provides new insights into the development of potential agents to control HBV infection.
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Parchment RE, Voth AR, Doroshow JH, Berzofsky JA. Immuno-pharmacodynamics for evaluating mechanism of action and developing immunotherapy combinations. Semin Oncol 2016; 43:501-13. [PMID: 27663482 DOI: 10.1053/j.seminoncol.2016.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Immunotherapy has become a major modality of cancer treatment, with multiple new classes of immunotherapeutics recently entering the clinic and obtaining market approval from regulatory agencies. While the promise of these therapies is great, so is the number of possible combinations not only with each other but also with small molecule therapeutics. Furthermore, the observation of unusual dose-response relationships suggests a critical dependency of drug effectiveness on the dosage regimen (dose and schedule). Clinical pharmacodynamic (PD) biomarkers will be useful endpoints for confirming drug mechanism of action, evaluating combination therapies for synergy or antagonism, and identifying optimal dosage regimens. In contrast to conventional PD in which drug action occurs entirely within a single target cell (ie, is self-contained within the malignant cell), immunotherapy involves a complex mechanism of action with sequential steps that propagate through multiple cell types, both normal and malignant. Its intercellular pharmacology begins with molecular target engagement either on an immune effector cell or a malignant cell, followed by stimulatory biochemical and biological signals in immune effector cells, and then finally ends with activation of cell death mechanisms in malignant cells lying within a certain distance from the activated effector cells (immune cell-tumor cell proximity). Evaluating such "trans-cellular pharmacology," in which different steps of drug action are distributed across multiple cell types, requires novel microscopy and image analysis tools capable of quantifying PD-biomarker responses, mapping the responses onto the cellular geography of the tumor using phenotypic biomarkers to identify specific cell types, and finally analyzing the spatial relationships between biomarkers in the context of each cell's biological role. We have termed this form of nearest neighbor image analysis of drug action "proximity PD microscopy," to indicate the importance of the location of the PD-biomarker response within the cellular landscape of a tumor specimen. We discuss herein the major modes of immunotherapy, and lay out a blueprint for using PD assessment to optimize dosage regimens of single agents and guide development of combination immunotherapy regimens, using PD1/PD-L1 immune checkpoint inhibition as a case study.
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Affiliation(s)
- Ralph E Parchment
- Clinical Pharmacodynamics Program, Applied/Developmental Research Directorate, Leidos Biomedical Research, Inc, Frederick National Laboratory for Cancer Research, Frederick, MD.
| | - Andrea Regier Voth
- Clinical Pharmacodynamics Program, Applied/Developmental Research Directorate, Leidos Biomedical Research, Inc, Frederick National Laboratory for Cancer Research, Frederick, MD
| | - James H Doroshow
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD
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Mercadante ER, Lorenz UM. Breaking Free of Control: How Conventional T Cells Overcome Regulatory T Cell Suppression. Front Immunol 2016; 7:193. [PMID: 27242798 PMCID: PMC4870238 DOI: 10.3389/fimmu.2016.00193] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/02/2016] [Indexed: 01/10/2023] Open
Abstract
Conventional T (Tcon) cells are crucial in shaping the immune response, whether it is protection against a pathogen, a cytotoxic attack on tumor cells, or an unwanted response to self-antigens in the context of autoimmunity. In each of these immune settings, regulatory T cells (Tregs) can potentially exert control over the Tcon cell response, resulting in either suppression or activation of the Tcon cells. Under physiological conditions, Tcon cells are able to transiently overcome Treg-imposed restraints to mount a protective response against an infectious threat, achieving clonal expansion, differentiation, and effector function. However, evidence has accumulated in recent years to suggest that Tcon cell resistance to Treg-mediated suppression centrally contributes to the pathogenesis of autoimmune disease. Tipping the balance too far in the other direction, cancerous tumors utilize Tregs to establish an overly suppressive microenvironment, preventing antitumor Tcon cell responses. Given the wide-ranging clinical importance of the Tcon/Treg interaction, this review aims to provide a better understanding of what determines whether a Tcon cell is susceptible to Treg-mediated suppression and how perturbations to this finely tuned balance play a role in pathological conditions. Here, we focus in detail on the complex array of factors that confer Tcon cells with resistance to Treg suppression, which we have divided into two categories: (1) extracellular factor-mediated signaling and (2) intracellular signaling molecules. Further, we explore the therapeutic implications of manipulating the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway, which is proposed to be the convergence point of signaling pathways that mediate Tcon resistance to suppression. Finally, we address important unresolved questions on the timing and location of acquisition of resistance, and the stability of the “Treg-resistant” phenotype.
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Affiliation(s)
- Emily R Mercadante
- Department of Microbiology Immunology and Cancer Biology, Beirne Carter Center for Immunology Research, University of Virginia , Charlottesville, VA , USA
| | - Ulrike M Lorenz
- Department of Microbiology Immunology and Cancer Biology, Beirne Carter Center for Immunology Research, University of Virginia , Charlottesville, VA , USA
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Sharma Y, Ahmad A, Bashir S, Elahi A, Khan F. Implication of protein tyrosine phosphatase SHP-1 in cancer-related signaling pathways. Future Oncol 2016; 12:1287-98. [PMID: 26987952 DOI: 10.2217/fon-2015-0057] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The altered expression of SHP-1 (SH2 domain-containing protein tyrosine phosphatase) as a consequence of promoter hypermethylation or mutations has evidently been linked to cancer development. The notion of being a cancer drug target is conceivable as SHP-1 negatively regulates cell cycle and inflammatory pathways which are an inevitable part of oncogenic transformation. In the present review, we try to critically analyze the role of SHP-1 in cancer progression via regulating the above mentioned pathways with the major emphasis on cell cycle components and JAK/STAT pathway, commencing with the SHP-1 biology in immune cell signaling. Lastly, we have provided the future directions for researchers to encourage SHP-1 as a prognostic marker and curative target for this debilitating disease called as cancer.
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Affiliation(s)
- Yadhu Sharma
- Department of Biochemistry, Faculty of Science, Jamia Hamdard, New Delhi-110062, India
| | - Altaf Ahmad
- Department of Botany, Aligarh Muslim University, Aligarh, Uttar Pradesh-202002, India
| | - Samina Bashir
- Department of Biochemistry, Faculty of Science, Jamia Hamdard, New Delhi-110062, India
| | - Asif Elahi
- Centre for Cellular & Molecular Biology (Council for Scientific & Industrial Research), Uppal Road, Hyderabad, Telangana-500007, India
| | - Farah Khan
- Department of Biochemistry, Faculty of Science, Jamia Hamdard, New Delhi-110062, India
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11
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Paster W, Bruger AM, Katsch K, Grégoire C, Roncagalli R, Fu G, Gascoigne NRJ, Nika K, Cohnen A, Feller SM, Simister PC, Molder KC, Cordoba SP, Dushek O, Malissen B, Acuto O. A THEMIS:SHP1 complex promotes T-cell survival. EMBO J 2014; 34:393-409. [PMID: 25535246 PMCID: PMC4339124 DOI: 10.15252/embj.201387725] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
THEMIS is critical for conventional T-cell development, but its precise molecular function remains elusive. Here, we show that THEMIS constitutively associates with the phosphatases SHP1 and SHP2. This complex requires the adapter GRB2, which bridges SHP to THEMIS in a Tyr-phosphorylation-independent fashion. Rather, SHP1 and THEMIS engage with the N-SH3 and C-SH3 domains of GRB2, respectively, a configuration that allows GRB2-SH2 to recruit the complex onto LAT. Consistent with THEMIS-mediated recruitment of SHP to the TCR signalosome, THEMIS knock-down increased TCR-induced CD3-ζ phosphorylation, Erk activation and CD69 expression, but not LCK phosphorylation. This generalized TCR signalling increase led to augmented apoptosis, a phenotype mirrored by SHP1 knock-down. Remarkably, a KI mutation of LCK Ser59, previously suggested to be key in ERK-mediated resistance towards SHP1 negative feedback, did not affect TCR signalling nor ligand discrimination in vivo. Thus, the THEMIS:SHP complex dampens early TCR signalling by a previously unknown molecular mechanism that favours T-cell survival. We discuss possible implications of this mechanism in modulating TCR output signals towards conventional T-cell development and differentiation.
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Affiliation(s)
- Wolfgang Paster
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Annika M Bruger
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Kristin Katsch
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Claude Grégoire
- Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France INSERM U1104, Marseille, France CNRS UMR7280, Marseille, France
| | - Romain Roncagalli
- Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France INSERM U1104, Marseille, France CNRS UMR7280, Marseille, France
| | - Guo Fu
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA
| | - Nicholas R J Gascoigne
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Konstantina Nika
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Andre Cohnen
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Stephan M Feller
- Biological Systems Architecture Group, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK Tumor Biology Unit, Institute of Molecular Medicine, ZAMED, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Philip C Simister
- Biological Systems Architecture Group, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Kelly C Molder
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Shaun-Paul Cordoba
- Molecular Immunology Group, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Omer Dushek
- Molecular Immunology Group, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Bernard Malissen
- Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France INSERM U1104, Marseille, France CNRS UMR7280, Marseille, France
| | - Oreste Acuto
- T Cell Signalling Laboratory, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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12
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Wolchinsky R, Hod-Marco M, Oved K, Shen-Orr SS, Bendall SC, Nolan GP, Reiter Y. Antigen-dependent integration of opposing proximal TCR-signaling cascades determines the functional fate of T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2014; 192:2109-19. [PMID: 24489091 DOI: 10.4049/jimmunol.1301142] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
T cell anergy is a key tolerance mechanism to mitigate unwanted T cell activation against self by rendering lymphocytes functionally inactive following Ag encounter. Ag plays an important role in anergy induction where high supraoptimal doses lead to the unresponsive phenotype. How T cells "measure" Ag dose and how this determines functional output to a given antigenic dose remain unclear. Using multiparametric phospho-flow and mass cytometry, we measured the intracellular phosphorylation-dependent signaling events at a single-cell resolution and studied the phosphorylation levels of key proximal human TCR activation- and inhibition-signaling molecules. We show that the intracellular balance and signal integration between these opposing signaling cascades serve as the molecular switch gauging Ag dose. An Ag density of 100 peptide-MHC complexes/cell was found to be the transition point between dominant activation and inhibition cascades, whereas higher Ag doses induced an anergic functional state. Finally, the neutralization of key inhibitory molecules reversed T cell unresponsiveness and enabled maximal T cell functions, even in the presence of very high Ag doses. This mechanism permits T cells to make integrated "measurements" of Ag dose that determine subsequent functional outcomes.
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Affiliation(s)
- Ron Wolchinsky
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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13
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Le Page A, Fortin C, Garneau H, Allard N, Tsvetkova K, Tan CTY, Larbi A, Dupuis G, Fülöp T. Downregulation of inhibitory SRC homology 2 domain-containing phosphatase-1 (SHP-1) leads to recovery of T cell responses in elderly. Cell Commun Signal 2014; 12:2. [PMID: 24405902 PMCID: PMC3896791 DOI: 10.1186/1478-811x-12-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 01/04/2014] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Immune responses are generally impaired in aged mammals. T cells have been extensively studied in this context due to the initial discovery of their reduced proliferative capacity with aging. The decreased responses involve altered signaling events associated with the early steps of T cell activation. The underlying causes of these changes are not fully understood but point to alterations in assembly of the machinery for T cell activation. Here, we have tested the hypothesis that the T cell pool in elderly subjects displayed reduced functional capacities due to altered negative feedback mechanisms that participate in the regulation of the early steps of T cell activation. Such conditions tip the immune balance in favor of altered T cell activation and a related decreased response in aging. RESULTS We present evidence that the tyrosine phosphatase SHP-1, a key regulator of T cell signal transduction machinery is, at least in part, responsible for the impaired T cell activation in aging. We used tyrosine-specific mAbs and Western blot analysis to show that a deregulation of the Csk/PAG loop in activated T cells from elderly individuals favored the inactive form of tyrosine-phosphorylated Lck (Y505). Confocal microscopy analysis revealed that the dynamic movements of these regulatory proteins in lipid raft microdomains was altered in T cells of aged individuals. Enzymic assays showed that SHP-1 activity was upregulated in T cells of aged donors, in contrast to young subjects. Pharmacological inhibition of SHP-1 resulted in recovery of TCR/CD28-dependent lymphocyte proliferation and IL-2 production of aged individuals to levels approaching those of young donors. Significant differences in the active (Y394) and inactive (Y505) phosphorylation sites of Lck in response to T cell activation were observed in elderly donors as compared to young subjects, independently of CD45 isoform expression. CONCLUSIONS Our data suggest that the role of SHP-1 in T cell activation extends to its increased effect in negative feedback in aging. Modulation of SHP-1 activity could be a target to restore altered T cell functions in aging. These observations could have far reaching consequences for improvement of immunosenescence and its clinical consequences such as infections, altered response to vaccination.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Tamas Fülöp
- Research Center on Aging, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 1036 rue Belvedere sud, Sherbrooke, J1H 4C4, Quebec, Canada.
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14
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Tomar N, De RK. A model of an integrated immune system pathway in Homo sapiens and its interaction with superantigen producing expression regulatory pathway in Staphylococcus aureus: comparing behavior of pathogen perturbed and unperturbed pathway. PLoS One 2013; 8:e80918. [PMID: 24324645 PMCID: PMC3855681 DOI: 10.1371/journal.pone.0080918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 10/17/2013] [Indexed: 11/19/2022] Open
Abstract
Response of an immune system to a pathogen attack depends on the balance between the host immune defense and the virulence of the pathogen. Investigation of molecular interactions between the proteins of a host and a pathogen helps in identifying the pathogenic proteins. It is necessary to understand the dynamics of a normally behaved host system to evaluate the capacity of its immune system upon pathogen attack. In this study, we have compared the behavior of an unperturbed and pathogen perturbed host system. Moreover, we have developed a formalism under Flux Balance Analysis (FBA) for the optimization of conflicting objective functions. We have constructed an integrated pathway system, which includes Staphylococcal Superantigen (SAg) expression regulatory pathway and TCR signaling pathway of Homo sapiens. We have implemented the method on this pathway system and observed the behavior of host signaling molecules upon pathogen attack. The entire study has been divided into six different cases, based on the perturbed/unperturbed conditions. In other words, we have investigated unperturbed and pathogen perturbed human TCR signaling pathway, with different combinations of optimization of concentrations of regulatory and signaling molecules. One of these cases has aimed at finding out whether minimization of the toxin production in a pathogen leads to the change in the concentration levels of the proteins coded by TCR signaling pathway genes in the infected host. Based on the computed results, we have hypothesized that the balance between TCR signaling inhibitory and stimulatory molecules can keep TCR signaling system into resting/stimulating state, depending upon the perturbation. The proposed integrated host-pathogen interaction pathway model has accurately reflected the experimental evidences, which we have used for validation purpose. The significance of this kind of investigation lies in revealing the susceptible interaction points that can take back the Staphylococcal Enterotoxin (SE)-challenged system within the range of normal behavior.
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Affiliation(s)
- Namrata Tomar
- Machine Intelligence Unit, Indian Statistical Institute, Kolkata, India
| | - Rajat K. De
- Machine Intelligence Unit, Indian Statistical Institute, Kolkata, India
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15
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Abstract
Tyrosine phosphorylation is one of the key covalent modifications that occur in multicellular organisms. Since its discovery more than 30 years ago, tyrosine phosphorylation has come to be understood as a fundamentally important mechanism of signal transduction and regulation in all eukaryotic cells. The tyrosine kinase Lck (lymphocyte-specific protein tyrosine kinase) plays a crucial role in the T-cell response by transducing early activation signals triggered by TCR (T-cell receptor) engagement. These signals result in the phosphorylation of immunoreceptor tyrosine-based activation motifs present within the cytosolic tails of the TCR-associated CD3 subunits that, once phosphorylated, serve as scaffolds for the assembly of a large supramolecular signalling complex responsible for T-cell activation. The existence of membrane nano- or micro-domains or rafts as specialized platforms for protein transport and cell signalling has been proposed. The present review discusses the signals that target Lck to membrane rafts and the importance of these specialized membranes in the transport of Lck to the plasma membrane, the regulation of Lck activity and the phosphorylation of the TCR.
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16
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Wang R, Bi J, Ampah KK, Ba X, Liu W, Zeng X. Lipid rafts control human melanoma cell migration by regulating focal adhesion disassembly. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:3195-3205. [PMID: 24055995 DOI: 10.1016/j.bbamcr.2013.09.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 08/25/2013] [Accepted: 09/09/2013] [Indexed: 10/26/2022]
Abstract
Tumor cell migration is a crucial step in the metastatic cascade, and interruption of this step is considered to be logically effective in preventing tumor metastasis. Lipid rafts, distinct liquid ordered plasma membrane microdomains, have been shown to influence cancer cell migration, but the underlying mechanisms are still not well understood. Here, we report that lipid rafts regulate the dynamics of actin cytoskeleton and focal adhesion in human melanoma cell migration. Disrupting the integrity of lipid rafts with methyl-β cyclodextrin enhances actin stress fiber formation and inhibits focal adhesion disassembly, accompanied with alterations in cell morphology. Furthermore, actin cytoskeleton, rather than microtubules, mediates the lipid raft-dependent focal adhesion disassembly by regulating the dephosphorylation of focal adhesion proteins and the internalization of β3 integrin. We also show that Src-RhoA-Rho kinase signaling pathway is responsible for lipid raft disruption-induced stress fiber formation. Taken together, these observations provide a new mechanism to further explain how lipid rafts regulate the migration of melanoma cell and suggest that lipid rafts may be novel and attractive targets for cancer therapy.
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Affiliation(s)
- Ruifei Wang
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China
| | - Jiajia Bi
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China
| | - Khamal Kwesi Ampah
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China
| | - Xueqing Ba
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China.
| | - Wenguang Liu
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China
| | - Xianlu Zeng
- Institute of Genetics and Cytology, School of Life Sciences, Northeast Normal University, #5268, Renmin Street, Changchun, Jilin 130024, China.
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17
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Pike KA, Tremblay ML. Regulating naïve and memory CD8 T cell homeostasis - a role for protein tyrosine phosphatases. FEBS J 2012; 280:432-44. [DOI: 10.1111/j.1742-4658.2012.08587.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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18
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Mittal Y, Pavlova Y, Garcia-Marcos M, Ghosh P. Src homology domain 2-containing protein-tyrosine phosphatase-1 (SHP-1) binds and dephosphorylates G(alpha)-interacting, vesicle-associated protein (GIV)/Girdin and attenuates the GIV-phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway. J Biol Chem 2011; 286:32404-15. [PMID: 21799016 PMCID: PMC3173146 DOI: 10.1074/jbc.m111.275685] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 07/26/2011] [Indexed: 12/12/2022] Open
Abstract
GIV (Gα-interacting vesicle-associated protein, also known as Girdin) is a bona fide enhancer of PI3K-Akt signals during a diverse set of biological processes, e.g. wound healing, macrophage chemotaxis, tumor angiogenesis, and cancer invasion/metastasis. We recently demonstrated that tyrosine phosphorylation of GIV by receptor and non-receptor-tyrosine kinases is a key step that is required for GIV to directly bind and enhance PI3K activity. Here we report the discovery that Src homology 2-containing phosphatase-1 (SHP-1) is the major protein-tyrosine phosphatase that targets two critical phosphotyrosines within GIV and antagonizes phospho-GIV-dependent PI3K enhancement in mammalian cells. Using phosphorylation-dephosphorylation assays, we demonstrate that SHP-1 is the major and specific protein-tyrosine phosphatase that catalyzes the dephosphorylation of tyrosine-phosphorylated GIV in vitro and inhibits ligand-dependent tyrosine phosphorylation of GIV downstream of both growth factor receptors and GPCRs in cells. In vitro binding and co-immunoprecipitation assays demonstrate that SHP-1 and GIV interact directly and constitutively and that this interaction occurs between the SH2 domain of SHP-1 and the C terminus of GIV. Overexpression of SHP-1 inhibits tyrosine phosphorylation of GIV and formation of phospho-GIV-PI3K complexes, and specifically suppresses GIV-dependent activation of Akt. Consistently, depletion of SHP-1 enhances peak tyrosine phosphorylation of GIV, which coincides with an increase in peak Akt activity. We conclude that SHP-1 antagonizes the action of receptor and non-receptor-tyrosine kinases on GIV and down-regulates the phospho-GIV-PI3K-Akt axis of signaling.
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Affiliation(s)
| | | | - Mikel Garcia-Marcos
- Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093
| | - Pradipta Ghosh
- From the Departments of Medicine and
- Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093
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19
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Balagopalan L, Ashwell BA, Bernot KM, Akpan IO, Quasba N, Barr VA, Samelson LE. Enhanced T-cell signaling in cells bearing linker for activation of T-cell (LAT) molecules resistant to ubiquitylation. Proc Natl Acad Sci U S A 2011; 108:2885-90. [PMID: 21282648 PMCID: PMC3041139 DOI: 10.1073/pnas.1007098108] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Linker for activation of T cells (LAT) plays a central role in T-cell activation by nucleating signaling complexes that are critical for the propagation of T-cell signals from the plasma membrane to the cellular interior. The role of phosphorylation and palmitoylation in LAT function has been well studied, but not much is known about other strategies by which the cell modulates LAT activity. We have focused on LAT ubiquitylation and have mapped the sites on which LAT is ubiquitylated. To elucidate the biological role of this process, we substituted LAT lysines with arginines. This resulted in a dramatic decrease in overall LAT ubiquitylation. Ubiquitylation-resistant mutants of LAT were internalized at rates comparable to wild-type LAT in a mechanism that required Cbl family proteins. However, these mutants displayed a defect in protein turnover rates. T-cell signaling was elevated in cells reconstituted with LAT mutants resistant to ubiquitylation, indicating that inhibition of LAT ubiquitylation enhances T-cell potency. These results support LAT ubiquitylation as a molecular checkpoint for attenuation of T-cell signaling.
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Affiliation(s)
- Lakshmi Balagopalan
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Benjamin A. Ashwell
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | | | - Itoro O. Akpan
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Naeha Quasba
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Valarie A. Barr
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Lawrence E. Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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20
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Schmitt TM, Ragnarsson GB, Greenberg PD. T cell receptor gene therapy for cancer. Hum Gene Ther 2010; 20:1240-8. [PMID: 19702439 DOI: 10.1089/hum.2009.146] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
T cell-based adoptive immunotherapy has been shown to be a promising treatment for various types of cancer. However, adoptive T cell therapy currently requires the custom isolation and characterization of tumor-specific T cells from each patient-a process that can be not only difficult and time-consuming but also often fails to yield high-avidity T cells, which together have limited the broad application of this approach as a clinical treatment. Employing T cell receptor (TCR) gene therapy as a component of adoptive T cell therapy strategies can overcome many of these obstacles, allowing autologous T cells with a defined specificity to be generated in a much shorter time period. Initial studies using this approach have been hampered by a number of technical difficulties resulting in low TCR expression and acquisition of potentially problematic specificities due to mispairing of introduced TCR chains with endogenous TCR chains. The last several years have seen substantial progress in our understanding of the multiple facets of TCR gene therapy that will have to be properly orchestrated for this strategy to succeed. Here we outline the challenges of TCR gene therapy and the advances that have been made toward realizing the promise of this approach.
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21
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Fowler CC, Pao LI, Blattman JN, Greenberg PD. SHP-1 in T cells limits the production of CD8 effector cells without impacting the formation of long-lived central memory cells. THE JOURNAL OF IMMUNOLOGY 2010; 185:3256-67. [PMID: 20696858 DOI: 10.4049/jimmunol.1001362] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
During responses against viruses and malignancies, naive CD8 T lymphocytes expand to form both short-lived effector cells and a population containing cells with the potential to be long-lived and participate in memory responses (memory precursor effector cells). The strength of antigenic, costimulatory, and cytokine signals during responses impacts the magnitude and type of CD8 populations formed. In vitro studies have revealed that the tyrosine phosphatase Src homology region 2 domain-containing phosphatase-1 (SHP-1) regulates signal transduction from receptors on T cells including the TCR, helping set the activation threshold, and therefore may shape responses of mature CD8 T cells in vivo. Analysis of CD8 T cells from motheaten mice, which are globally deficient in SHP-1, proved problematic due to cell-extrinsic effects of SHP-1 deficiency in non-T cells on CD8 T cells. Therefore, a conditional knockout of SHP-1 in mature single-positive T cells was developed to analyze cell-intrinsic consequences of complete and partial SHP-1 deficiency on CD8 T cell responses to acute viral infection. The results demonstrated that SHP-1 has disparate effects on subpopulations of responding cells, limiting the magnitude and quality of primary and secondary responses by reducing the number of short-lived effector cells generated without affecting the size of the memory precursor effector cell pool that leads to formation of long-term memory.
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Affiliation(s)
- Carla C Fowler
- Department of Immunology, School of Medicine, University of Washington, Seattle, WA 98195- 6425, USA
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22
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Schnell FJ, Alberts-Grill N, Evavold BD. CD8+ T cell responses to a viral escape mutant epitope: active suppression via altered SHP-1 activity. THE JOURNAL OF IMMUNOLOGY 2009; 182:1829-35. [PMID: 19201834 DOI: 10.4049/jimmunol.0801798] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
One mechanism viruses use to subvert immune surveillance is through mutation of MHC contact residues of antigenic epitopes that weaken T cell recognition to the point that the immune system is ignorant of the infection. However, in contrast to ignorance, results presented herein demonstrate that intracellular signaling does occur upon stimulation with a lymphocytic choriomeningitis virus-derived escape mutant as demonstrated by the sustained activation of Src homology 2 domain-containing protein tyrosine phosphatase (SHP-1). In addition to the increased SHP-1 activity, we found that the mutated epitope failed to induce oxidation of SHP-1, further enhancing enzymatic activity. Sustained activation of SHP-1 in a reduced form correlated with ERK and early growth response gene 1 activation and failure of T cells to commit to the effector lineage. Thus, instead of immune ignorance, these studies demonstrate the activation of a negative signaling pathway that actively suppresses T cell responses and limits recognition of viral escape mutants.
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Affiliation(s)
- Frederick J Schnell
- Department of Microbiology and Immunology, Emory University, Atlanta, GA 30322, USA
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23
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Abstract
Tyrosine phosphorylation and dephosphorylation of proteins play a critical role for many T-cell functions. The opposing actions of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs) determine the level of tyrosine phosphorylation at any time. It is well accepted that PTKs are essential during T-cell signaling; however, the role and importance of PTPs are much less known and appreciated. Both transmembrane and cytoplasmic tyrosine phosphatases have been identified in T cells and shown to regulate T-cell responses. This review focuses on the roles of the two cytoplasmic PTPs, the Src-homology 2 domain (SH2)-containing SHP-1 and SHP-2, in T-cell signaling, development, differentiation, and function.
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Affiliation(s)
- Ulrike Lorenz
- Department of Microbiology and The Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville, VA 22908-0734, USA.
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24
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Sankarshanan M, Ma Z, Iype T, Lorenz U. Identification of a novel lipid raft-targeting motif in Src homology 2-containing phosphatase 1. THE JOURNAL OF IMMUNOLOGY 2007; 179:483-90. [PMID: 17579069 DOI: 10.4049/jimmunol.179.1.483] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The tyrosine phosphatase Src homology 2-containing phosphatase 1 (SHP-1) is a key negative regulator of TCR-mediated signaling. Previous studies have shown that in T cells a fraction of SHP-1 constitutively localizes to membrane microdomains, commonly referred to as lipid rafts. Although this localization of SHP-1 is required for its functional regulation of T cell activation events, how SHP-1 is targeted to the lipid rafts was unclear. In this study, we identify a novel, six-amino acid, lipid raft-targeting motif within the C terminus of SHP-1 based on several biochemical and functional observations. First, mutations of this motif in the context of full-length SHP-1 result in the loss of lipid raft localization of SHP-1. Second, this motif alone restores raft localization when fused to a mutant of SHP-1 (SHP-1 DeltaC) that fails to localize to rafts. Third, a peptide encompassing the 6-mer motif directly binds to phospholipids whereas a mutation of this motif abolishes lipid binding. Fourth, whereas full-length SHP-1 potently inhibits TCR-induced tyrosine phosphorylation of specific proteins, expression of a SHP-1-carrying mutation within the 6-mer motif does not. Additionally, although SHP-1 DeltaC was functionally inactive, the addition of the 6-mer motif restored its functionality in inhibiting TCR-induced tyrosine phosphorylation. Finally, this 6-mer mediated targeting of SHP-1 lipid rafts was essential for the function of this phosphatase in regulating IL-2 production downstream of TCR. Taken together, these data define a novel 6-mer motif within SHP-1 that is necessary and sufficient for lipid raft localization and for the function of SHP-1 as a negative regulator of TCR signaling.
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Affiliation(s)
- Mohan Sankarshanan
- Department of Microbiology, University of Virginia Health System, Charlottesville, VA 22908, USA
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25
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Liu Y, Kruhlak MJ, Hao JJ, Shaw S. Rapid T cell receptor-mediated SHP-1 S591 phosphorylation regulates SHP-1 cellular localization and phosphatase activity. J Leukoc Biol 2007; 82:742-51. [PMID: 17575265 PMCID: PMC2084461 DOI: 10.1189/jlb.1206736] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Since the tyrosine phosphatase SHP-1 plays a major role in regulating T cell signaling, we investigated regulation thereof by Ser/Thr phosphorylation. We found that T cell receptor (TCR) stimulation induced fast (<or=1 min) and transient phosphorylation of SHP-1 S591 in both Jurkat and human peripheral blood T-cells (PBT). Phosphorylation of S591 in T-cells could be mediated artificially by a constitutive active PKC-theta construct, but the dose dependence of inhibition by PKC inhibitors indicated that PKCs were not the relevant basophilic kinase in the physiological response. S591 phosphorylation inhibited phosphatase function since a S591D mutant had lower activity than the S591A mutant. Additional evidence that S591 phosphorylation alters SHP-1 function was provided by studies of Jurkat cells stably expressing SHP-1 wild type or mutants. In those cells, S591D mutation reduced the capacity of transfected SHP-1 to inhibit TCR-induced phosphorylation of PLC-gamma1. Interestingly, SHP-1 Y536 phosphorylation (previously shown to augment phosphatase activity) was also induced in PBT by TCR signal but at a much later time compared with S591 ( approximately 30 min). S591 phosphorylation also altered cellular distribution of SHP-1 because: 1) SHP-1 in lipid rafts and a sheared membrane fraction was hypophosphorylated; 2) In stably transfected Jurkat cell lines, S591D mutant protein had reduced presence in both lipid raft and the sheared membrane fraction; 3) S591 phosphorylation prevented nuclear localization of a C-terminal GFP tagged SHP-1 construct. Our studies also shed light on an additional mechanism regulating SHP-1 nuclear localization, namely conformational autoinhibition. These findings highlight elegant regulation of SHP-1 by sequential phosphorylation of serine then tyrosine.
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Affiliation(s)
- Yin Liu
- Experimental Immunology Branch, Bldg. 10/4B05 National Cancer Institute, NIH Bethesda, MD 20892, USA
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26
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Abstract
Tyrosyl phosphorylation plays a critical role in multiple signaling pathways regulating innate and acquired immunity. Although tyrosyl phosphorylation is a reversible process, we know much more about the functions of protein-tyrosine kinases (PTKs) than about protein-tyrosine phosphatases (PTPs). Genome sequencing efforts have revealed a large and diverse superfamily of PTPs, which can be subdivided into receptor-like (RPTPs) and nonreceptor (NRPTPs). The role of the RPTP CD45 in immune cell signaling is well known, but those of most other PTPs remain poorly understood. Here, we review the mechanism of action, regulation, and physiological functions of NRPTPs in immune cell signaling. Such an analysis indicates that PTPs are as important as PTKs in regulating the immune system.
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Affiliation(s)
- Lily I Pao
- Cancer Biology Program, Division of Hematology-Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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27
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Sitrin RG, Emery SL, Sassanella TM, Blackwood RA, Petty HR. Selective localization of recognition complexes for leukotriene B4 and formyl-Met-Leu-Phe within lipid raft microdomains of human polymorphonuclear neutrophils. THE JOURNAL OF IMMUNOLOGY 2007; 177:8177-84. [PMID: 17114494 DOI: 10.4049/jimmunol.177.11.8177] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neutrophilic polymorphonuclear leukocytes contain glycosphingolipid- and cholesterol-enriched lipid raft microdomains within the plasma membrane. Although there is evidence that lipid rafts function as signaling platforms for CXCR chemokine receptors, their role in recognition systems for other chemotaxins such as leukotriene B4 (LTB4) and fMLP is unknown. To address this question, human neutrophils were extracted with 1% Brij-58 and fractionated on sucrose gradients. B leukotriene receptor-1 (BLT-1), the primary LTB4 receptor, partitioned to low density fractions, co-isolating with the lipid raft marker, flotillin-1. By contrast, formyl peptide receptor (FPR), the primary fMLP receptor, partitioned to high density fractions, co-isolating with a non-raft marker, Cdc42. This pattern was preserved after the cells were stimulated with LTB4 or fMLP. Fluorescence resonance energy transfer (FRET) was performed to confirm the proximity of BLT-1 and FPR with these markers. FRET was detected between BLT1 and flotillin-1 but not Cdc42, whereas FRET was detected between FPR and Cdc42, but not flotillin-1. Pretreating neutrophils with methyl-beta-cyclodextrin, a lipid raft-disrupting agent, suppressed intracellular Ca(2+) mobilization and ERK1/2 phosphorylation in response to LTB4 but had no effect on either of these responses to fMLP. We conclude that BLT-1 is physically located within lipid raft microdomains of human neutrophils and that disrupting lipid raft integrity suppresses LTB4-induced activation. By contrast, FPR is not associated with lipid rafts, and fMLP-induced signaling does not require lipid raft integrity. These findings highlight the complexity of chemotaxin signaling pathways and offer one mechanism by which neutrophils may spatially organize chemotaxin signaling within the plasma membrane.
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Affiliation(s)
- Robert G Sitrin
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, 1150 West Medical Drive, Ann Arbor, MI 48109, USA.
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28
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Masilamani M, Nguyen C, Kabat J, Borrego F, Coligan JE. CD94/NKG2A inhibits NK cell activation by disrupting the actin network at the immunological synapse. THE JOURNAL OF IMMUNOLOGY 2006; 177:3590-6. [PMID: 16951318 DOI: 10.4049/jimmunol.177.6.3590] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
An adequate immune response is the result of the fine balance between activation and inhibitory signals. The exact means by which inhibitory signals obviate activation signals in immune cells are not totally elucidated. Human CD94/NKG2A is an ITIM-containing inhibitory receptor expressed by NK cells and some CD8+ T cells that recognize HLA-E. We show that the engagement of this receptor prevents NK cell activation by disruption of the actin network and exclusion of lipid rafts at the point of contact with its ligand (inhibitory NK cell immunological synapse, iNKIS). CD94/NKG2A engagement leads to recruitment and activation of src homology 2 domain-bearing tyrosine phosphatase 1. This likely explains the observed dephosphorylation of guanine nucleotide exchange factor and regulator of actin, Vav1, as well as ezrin-radixin-moesin proteins that connect actin filaments to membrane structures. In contrast, NK cell activation by NKG2D induced Vav1 and ezrin-radixin-moesin phosphorylation. Thus, CD94/NKG2A prevents actin-dependent recruitment of raft-associated activation receptors complexes to the activating synapse. This was further substantiated by showing that inhibition of actin polymerization abolished lipid rafts exclusion at the iNKIS, whereas cholesterol depletion had no effect on actin disruption at the iNKIS. These data indicate that the lipid rafts exclusion at the iNKIS is an active process which requires an intact cytoskeleton to maintain lipid rafts outside the inhibitory synapse. The net effect is to maintain an inhibitory state in the proximity of the iNKIS, while allowing the formation of activation synapse at distal points within the same NK cell.
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Affiliation(s)
- Madhan Masilamani
- Receptor Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
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Kim HY, Park SJ, Joe EH, Jou I. Raft-mediated Src Homology 2 Domain-containing Proteintyrosine Phosphatase 2 (SHP-2) Regulation in Microglia. J Biol Chem 2006; 281:11872-8. [PMID: 16507579 DOI: 10.1074/jbc.m511706200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Janus kinase-signal transducer and activator of transcription (JAK-STAT) signals play important roles in cell proliferation, apoptosis, and inflammation, and they recently have been considered as therapeutic targets for suppressing oncogenesis and inflammatory process. Phosphatases including Src homology 2 domain-containing protein-tyrosine phosphatases (SHPs), are well known as negative regulators of the JAK-STAT pathway, but their precise mechanisms are largely unknown. Based on our previous finding that in cultured rat brain microglia, gangliosides induce rapid and transient activation of the JAK-STAT pathway, we hypothesized that raft-mediated SHP-2 activation is involved in transient activation of JAK-STAT signaling by gangliosides. We first used Western blot analysis to confirm that gangliosides rapidly induce the phosphorylation of SHP-2. This was inhibited by pretreatment with the lipid raft disrupter filipin and was restored following filipin removal. Immunostaining using antibodies directed against p-SHP-2 and flotillin-1 revealed ganglioside-induced clustering and polarization of p-SHP-2 in membrane rafts. Raft-associated regulation of SHP-2 was further demonstrated in fractionation experiments using detergent and detergent-free sucrose gradient ultracentrifugation. Rapid SHP-2 recruitment to detergent-insoluble raft fractions by gangliosides was inhibited by filipin, further indicating the involvement of rafts. We also confirmed by immunoprecipitation that SHP-2 rapidly binds in a raft-dependent manner to JAK2 in response to gangliosides. Our study therefore showed that transient activation of the JAK-STAT pathway by gangliosides is accomplished by SHP-2 in a raft-dependent manner in brain microglia.
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Affiliation(s)
- Hee Young Kim
- Department of Pharmacology and Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon 442-721, Korea
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Fortin CF, Larbi A, Lesur O, Douziech N, Fulop T. Impairment of SHP-1 down-regulation in the lipid rafts of human neutrophils under GM-CSF stimulation contributes to their age-related, altered functions. J Leukoc Biol 2006; 79:1061-72. [PMID: 16501054 DOI: 10.1189/jlb.0805481] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
It has been shown that the functions and the rescue from apoptosis by proinflammatory mediators of polymorphonuclear leukocytes (PMN) tend to diminish with aging. Here, we investigated the role of protein tyrosine phosphatases (PTP), especially Src homology domain-containing protein tyrosine phosphatase-1 (SHP-1), in the age-related, altered PMN functions under granulocyte macrophage-colony stimulating factor (GM-CSF) stimulation. The inhibition of PTP suggested a differential effect of GM-CSF on phosphatase activity in modulating PMN functions with aging. The down-regulation of phosphatase activity of immunopurified SHP-1 from lipid rafts of PMN of young donors was found significantly altered at 1 min of stimulation with aging. In young donors, SHP-1 is displaced from lipid rafts at 1 min of stimulation, whereas in the elderly, SHP-1 is constantly present. We assessed in PMN lipid rafts the phosphorylation of tyrosine and serine residues of SHP-1, which regulates its activity. We observed an alteration in the phosphorylation of tyrosine and serine residues of SHP-1 in PMN of elderly subjects, suggesting that GM-CSF was unable to inhibit SHP-1 activity by serine phosphorylation. GM-CSF activates Lyn rapidly, and we found alterations in its activation and translocation to the lipid rafts with aging. We also demonstrate that SHP-1 in the PMN of elderly is constantly recruited to Lyn, which cannot be relieved by GM-CSF. In contrast, in the young, the resting recruitment could be relieved by GM-CSF. Our results suggest an alteration of the SHP-1 modulation by GM-CSF in lipid rafts of PMN with aging. These alterations could contribute to the decreased GM-CSF effects on PMN.
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Affiliation(s)
- Carl F Fortin
- Laboratory for Immunology, Research Center on Aging, Clinical Research Center, and Department of Medicine, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Québec, Canada
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31
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Poole AW, Jones ML. A SHPing tale: perspectives on the regulation of SHP-1 and SHP-2 tyrosine phosphatases by the C-terminal tail. Cell Signal 2005; 17:1323-32. [PMID: 16084691 DOI: 10.1016/j.cellsig.2005.05.016] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Accepted: 05/17/2005] [Indexed: 01/31/2023]
Abstract
Protein tyrosine phosphorylation is a ubiquitous signalling mechanism and is regulated by a balance between the action of kinases and phosphatases. The SH2 domain-containing phosphatases SHP-1 and SHP-2 are the best studied of the classical non-receptor tyrosine phosphatases, but it is intriguing that despite their close sequence and structural homology these two phosphatases play quite different cellular roles. In particular, whereas SHP-1 plays a largely negative signalling role suppressing cellular activation, SHP-2 plays a largely positive signalling role. Major sequence differences between the two molecules are apparent in the approximately 100 amino acid residues at the extreme C-terminus of the proteins, beyond the phosphatase catalytic domain. Here we review how the differences in the tails of these proteins may regulate their activities and explain some of their functional differences.
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Affiliation(s)
- Alastair W Poole
- Department of Pharmacology, University of Bristol, School of Medical Sciences, Bristol BS8 1TD, UK.
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Maeda M, Carpenito C, Russell RC, Dasanjh J, Veinotte LL, Ohta H, Yamamura T, Tan R, Takei F. Murine CD160, Ig-Like Receptor on NK Cells and NKT Cells, Recognizes Classical and Nonclassical MHC Class I and Regulates NK Cell Activation. THE JOURNAL OF IMMUNOLOGY 2005; 175:4426-32. [PMID: 16177084 DOI: 10.4049/jimmunol.175.7.4426] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Human and mouse NK cells use different families of receptors to recognize MHC class I (MHC I) on target cells. Although human NK cells express both Ig-like receptors and lectin-like receptors specific for MHC I, all the MHC I-specific receptors identified on mouse NK cells to date are lectin-like receptors, and no Ig-like receptors recognizing MHC I have been identified on mouse NK cells. In this study we report the first MHC I-specific Ig-like receptor on mouse NK cells, namely, murine CD160 (mCD160). The expression of mCD160 is restricted to a subset of NK cells, NK1.1+ T cells, and activated CD8+ T cells. The mCD160-Ig fusion protein binds to rat cell lines transfected with classical and nonclassical mouse MHC I, including CD1d. Furthermore, the level of mCD160 on NK1.1+ T cells is modulated by MHC I of the host. Overexpression of mCD160 in the mouse NK cell line KY-2 inhibits IFN-gamma production induced by phorbol ester plus ionomycin, whereas it enhances IFN-gamma production induced by NK1.1 cross-linking or incubation with dendritic cells. Cross-linking of mCD160 also inhibits anti-NK1.1-mediated stimulation of KY-2 cells. Anti-mCD160 mAb alone has no effect. Thus, mCD160, the first MHC I-specific Ig-like receptor on mouse NK cells, regulates NK cell activation both positively and negatively, depending on the stimulus.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Cells, Cultured
- DNA, Complementary/analysis
- GPI-Linked Proteins
- Histocompatibility Antigens Class I/metabolism
- Humans
- K562 Cells
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Ligands
- Lymphocyte Activation/immunology
- Male
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Rats
- Rats, Inbred F344
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- Motoi Maeda
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
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