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Singh U, Pawge G, Rani S, Hsiao CHC, Wiemer AJ, Wiemer DF. Diester Prodrugs of a Phosphonate Butyrophilin Ligand Display Improved Cell Potency, Plasma Stability, and Payload Internalization. J Med Chem 2023; 66:15309-15325. [PMID: 37934915 PMCID: PMC10683022 DOI: 10.1021/acs.jmedchem.3c01358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/16/2023] [Accepted: 10/19/2023] [Indexed: 11/09/2023]
Abstract
Activation of Vγ9Vδ2 T cells with butyrophilin 3A1 (BTN3A1) agonists such as (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) has the potential to boost the immune response. Because HMBPP is highly charged and metabolically unstable, prodrugs may be needed to overcome these liabilities, but the prodrugs themselves may be limited by slow payload release or low plasma stability. To identify effective prodrug forms of a phosphonate agonist of BTN3A1, we have prepared a set of diesters bearing one aryl and one acyloxymethyl group. The compounds were evaluated for their ability to stimulate Vγ9Vδ2 T cell proliferation, increase production of interferon γ, resist plasma metabolism, and internalize into leukemia cells. These bioassays have revealed that varied aryl and acyloxymethyl groups can decouple plasma and cellular metabolism and have a significant impact on bioactivity (>200-fold range) and stability (>10 fold range), including some with subnanomolar potency. Our findings increase the understanding of the structure-activity relationships of mixed aryl/acyloxymethyl phosphonate prodrugs.
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Affiliation(s)
- Umed Singh
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United
States
| | - Girija Pawge
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Sarita Rani
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Chia-Hung Christine Hsiao
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Andrew J. Wiemer
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
- Institute
for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269-3092, United
States
| | - David F. Wiemer
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United
States
- Department
of Pharmacology, University of Iowa, Iowa City, Iowa 52242-1109, United
States
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2
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The Multifaceted MEP Pathway: Towards New Therapeutic Perspectives. Molecules 2023; 28:molecules28031403. [PMID: 36771066 PMCID: PMC9919496 DOI: 10.3390/molecules28031403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 01/27/2023] [Accepted: 01/28/2023] [Indexed: 02/05/2023] Open
Abstract
Isoprenoids, a diverse class of natural products, are present in all living organisms. Their two universal building blocks are synthesized via two independent pathways: the mevalonate pathway and the 2-C-methyl-ᴅ-erythritol 4-phosphate (MEP) pathway. The presence of the latter in pathogenic bacteria and its absence in humans make all its enzymes suitable targets for the development of novel antibacterial drugs. (E)-4-Hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP), the last intermediate of this pathway, is a natural ligand for the human Vγ9Vδ2 T cells and the most potent natural phosphoantigen known to date. Moreover, 5-hydroxypentane-2,3-dione, a metabolite produced by Escherichia coli 1-deoxy-ᴅ-xylulose 5-phosphate synthase (DXS), the first enzyme of the MEP pathway, structurally resembles (S)-4,5-dihydroxy-2,3-pentanedione, a signal molecule implied in bacterial cell communication. In this review, we shed light on the diversity of potential uses of the MEP pathway in antibacterial therapies, starting with an overview of the antibacterials developed for each of its enzymes. Then, we provide insight into HMBPP, its synthetic analogs, and their prodrugs. Finally, we discuss the potential contribution of the MEP pathway to quorum sensing mechanisms. The MEP pathway, providing simultaneously antibacterial drug targets and potent immunostimulants, coupled with its potential role in bacterial cell-cell communication, opens new therapeutic perspectives.
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3
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Harmon N, Poe MM, Huang X, Singh R, Foust BJ, Hsiao CHC, Wiemer DF, Wiemer AJ. Synthesis and Metabolism of BTN3A1 Ligands: Studies on Diene Modifications to the Phosphoantigen Scaffold. ACS Med Chem Lett 2022; 13:164-170. [PMID: 35178171 PMCID: PMC8842111 DOI: 10.1021/acsmedchemlett.1c00408] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 01/24/2022] [Indexed: 02/08/2023] Open
Abstract
Phosphoantigens (pAgs) are small organophosphorus compounds such as (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) that trigger an immune response. These molecules bind to butyrophilin 3A1 (part of the HMBPP receptor) and activate Vγ9Vδ2 T cells. To explore the structure-activity relationships underlying this process, we evaluated a series of novel diene analogs of HMBPP. Here we report that prodrug forms of [(1E)-4-methylpenta-1,3-dien-1-yl] phosphonic acid that lack the allylic alcohol of HMBPP but instead contained a diene scaffold exhibit mid-nanomolar potency for the activation of Vγ9Vδ2 T cells. The compounds also trigger the production of T-cell interferon γ upon exposure to loaded K562 cells. Although both the allylic alcohol and the diene scaffold boost pAg activity, the combination of the two decreases the activity and results in glutathione conjugation. Together, these data show that the diene scaffold results in intermediate pAgs that may have implications for the mechanisms regulating the HMBPP receptor.
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Affiliation(s)
- Nyema
M. Harmon
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Michael M. Poe
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Xueting Huang
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Rohit Singh
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - Benjamin J. Foust
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Chia-Hung Christine Hsiao
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States
| | - David F. Wiemer
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States,Department
of Pharmacology, University of Iowa, Iowa City, Iowa 52242-1109, United States
| | - Andrew J. Wiemer
- Department
of Pharmaceutical Sciences, University of
Connecticut, Storrs, Connecticut 06269-3092, United States,Institute
for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269-3092, United States,
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4
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Harmon NM, Huang X, Hsiao CHC, Wiemer AJ, Wiemer DF. Incorporation of a FRET pair within a phosphonate diester. Bioorg Chem 2021; 114:105048. [PMID: 34126576 DOI: 10.1016/j.bioorg.2021.105048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/25/2021] [Accepted: 05/28/2021] [Indexed: 10/21/2022]
Abstract
Cell-cleavable protecting groups are an effective tactic for construction of biological probes because such compounds can improve problems with instability, solubility, and cellular uptake. Incorporation of fluorescent groups in the protecting groups may afford useful probes of cellular functions, especially for payloads containing phosphonates that would be highly charged if not protected, but little is known about the steric or electronic factors that impede release of the payload. In this report we present a strategy for the synthesis of a coumarin fluorophore and a 4-((4-(dimethylamino)phenyl)diazenyl)benzoic acid (DABCYL) ester chromophore incorporated as a FRET pair within a single phosphonate. Such compounds were designed to deliver a BTN3A1 ligand payload to its intracellular receptor. Both final products and some synthetic intermediates were evaluated for their ability to undergo metabolic activation in γδ T cell functional assays, and for their photophysical properties by spectrophotometry. One phosphonate bearing a DABCYL acyloxyester and a novel tyramine-linked coumarin fluorophore exhibited strong, rapid, and potent cellular activity for γδ T cell stimulation and also showed FRET interactions. This strategy demonstrates that bioactivatable phosphonates containing FRET pairs can be utilized to develop probes to monitor cellular uptake of otherwise charged payloads.
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Affiliation(s)
- Nyema M Harmon
- Department of Chemistry, The University of Iowa, Iowa City, IA 52245, United States
| | - Xueting Huang
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, United States
| | | | - Andrew J Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, United States; Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, United States
| | - David F Wiemer
- Department of Chemistry, The University of Iowa, Iowa City, IA 52245, United States; Department of Pharmacology, University of Iowa, Iowa City, IA 52242, United States.
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5
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Potent double prodrug forms of synthetic phosphoantigens. Bioorg Med Chem 2020; 28:115666. [DOI: 10.1016/j.bmc.2020.115666] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/19/2020] [Accepted: 07/22/2020] [Indexed: 12/24/2022]
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6
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Abstract
Phosphoantigens (pAgs) are small phosphorus-containing molecules that stimulate Vγ9Vδ2 T cells with sub-nanomolar cellular potency. Recent work has revealed that these compounds work through binding to the transmembrane immunoglobulin butyrophilin 3A1 (BTN3A1) within its intracellular B30.2 domain. Engagement of BTN3A1 is critical to the formation of an immune synapse between cells that contain pAgs and the Vγ9Vδ2 T cells. This minireview summarizes the structure-activity relationships of pAgs and their implications to the mechanisms of butyrophilin 3 activation leading to Vγ9Vδ2 T cell response.
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Affiliation(s)
- Andrew J Wiemer
- Department of Pharmaceutical Sciences and Institute for Systems Genomics, University of Connecticut, 69N. Eagleville Road, Storrs, CT, 06269, USA
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Yazdanifar M, Barbarito G, Bertaina A, Airoldi I. γδ T Cells: The Ideal Tool for Cancer Immunotherapy. Cells 2020; 9:E1305. [PMID: 32456316 PMCID: PMC7290982 DOI: 10.3390/cells9051305] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/27/2022] Open
Abstract
γδ T cells have recently gained considerable attention as an attractive tool for cancer adoptive immunotherapy due to their potent anti-tumor activity and unique role in immunosurveillance. The remarkable success of engineered T cells for the treatment of hematological malignancies has revolutionized the field of adoptive cell immunotherapy. Accordingly, major efforts are underway to translate this exciting technology to the treatment of solid tumors and the development of allogeneic therapies. The unique features of γδ T cells, including their major histocompatibility complex (MHC)-independent anti-cancer activity, tissue tropism, and multivalent response against a broad spectrum of the tumors, render them ideal for designing universal 'third-party' cell products, with the potential to overcome the challenges of allogeneic cell therapy. In this review, we describe the crucial role of γδ T cells in anti-tumor immunosurveillance and we summarize the different approaches used for the ex vivo and in vivo expansion of γδ T cells suitable for the development of novel strategies for cancer therapy. We further discuss the different transduction strategies aiming at redirecting or improving the function of γδ T cells, as well as, the considerations for the clinical applications.
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Affiliation(s)
- Mahboubeh Yazdanifar
- Stem Cell Transplantation and Regenerative Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA 94305, USA; (M.Y.); (G.B.)
| | - Giulia Barbarito
- Stem Cell Transplantation and Regenerative Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA 94305, USA; (M.Y.); (G.B.)
| | - Alice Bertaina
- Stem Cell Transplantation and Regenerative Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA 94305, USA; (M.Y.); (G.B.)
| | - Irma Airoldi
- Laboratorio Cellule Staminali post-natali e Terapie Cellulari, IRCCS G. Gaslini, Via G. Gaslini 5, 16147 Genova, Italy
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8
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Imbert C, Olive D. γδ T Cells in Tumor Microenvironment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1273:91-104. [PMID: 33119877 DOI: 10.1007/978-3-030-49270-0_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Gamma delta (γδ) T cells which combine both innate and adaptive potential have extraordinary properties. Indeed, their strong cytotoxic and pro-inflammatory activity allows them to kill a broad range of tumor cells. Several studies have demonstrated that γδ T cells are an important component of tumor-infiltrated lymphocytes in patients affected by different types of cancer. Tumor-infiltrating γδ T cells are also considered as a good prognostic marker in many studies, though the presence of these cells is associated with poor prognosis in breast and colon cancers. The tumor microenvironment seems to drive γδ T-cell differentiation toward a tumor-promoting or a tumor-controlling phenotype, which suggests that some tumor microenvironments can limit the effectiveness of γδ T cells.The major γδ T-cell subsets in human are the Vγ9Vδ2 T cells that are specifically activated by phosphoantigens. This unique antigenic activation process operates in a framework that requires the expression of butyrophilin 3A (BTN3A) molecules. Interestingly, there is some evidence that BTN3A expression may be regulated by the tumor microenvironment. Given their strong antitumoral potential, Vγ9Vδ2 T cells are used in therapeutic approaches either by ex vivo culture and amplification, and then adoptive transfer to patients or by direct stimulation to propagate in vivo. These strategies have demonstrated promising initial results, but greater potency is needed. Combining Vγ9Vδ2 T-cell immunotherapy with systemic approaches to restore antitumor immune response in tumor microenvironment may improve efficacy.In this chapter, we first review the basic features of γδ T cells and their roles in the tumor microenvironment and then analyze the advances about the understanding of these cells' activation in tumors and why this represent unique challenges for therapeutics, and finally we discuss γδ T-cell-based therapeutic strategies and future perspectives of their development.
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Affiliation(s)
- Caroline Imbert
- Inserm, U1068, Centre de Recherche en Cancérologie de Marseille (CRCM), Immunity and Cancer, Institut Paoli Calmettes, Aix Marseille Université, Marseille, France.,Immunomonitoring Platform, Institut Paoli Calmettes, Marseille, France
| | - Daniel Olive
- Inserm, U1068, Centre de Recherche en Cancérologie de Marseille (CRCM), Immunity and Cancer, Institut Paoli Calmettes, Aix Marseille Université, Marseille, France. .,Immunomonitoring Platform, Institut Paoli Calmettes, Marseille, France.
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9
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Lentini NA, Hsiao CHC, Crull GB, Wiemer AJ, Wiemer DF. Synthesis and Bioactivity of the Alanyl Phosphonamidate Stereoisomers Derived from a Butyrophilin Ligand. ACS Med Chem Lett 2019; 10:1284-1289. [PMID: 31531198 DOI: 10.1021/acsmedchemlett.9b00153] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 08/06/2019] [Indexed: 02/07/2023] Open
Abstract
Aryloxy phosphonamidate derivatives of a butyrophilin 3A1 ligand are stimulants of Vγ9 Vδ2 T cells. However, when bonded to an aryl ester and an amine, the phosphorus is stereogenic, and past compounds were studied as racemates. To determine the impact of stereochemistry on the activity, we now have prepared phosphonate derivatives of l- and d-alanine ethyl ester, separated the diastereomers, and evaluated their biological activity as single stereoisomers. The results demonstrate that phosphonamidates substituted with l-alanine stimulate Vγ9 Vδ2 T cells at lower concentrations than the racemic glycine counterpart, while those derived from d-alanine require higher concentrations. All four diastereomers are more active than charged phosphoantigens such as HMBPP. Surprisingly, only a 2-fold difference was observed between the l-alanine phosphorus isomers, with the R P isomer more potent. This suggests that the small phosphoantigen scaffold reduces but does not eliminate dependence upon phosphorus stereochemistry for cellular activity.
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Affiliation(s)
- Nicholas A. Lentini
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Chia-Hung Christine Hsiao
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269-3092, United States
| | - George B. Crull
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Andrew J. Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269-3092, United States
- Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269-3092, United States
| | - David F. Wiemer
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
- Department of Pharmacology, University of Iowa, Iowa City, Iowa 52242-1109, United States
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10
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Foust BJ, Li J, Hsiao CHC, Wiemer DF, Wiemer AJ. Stability and Efficiency of Mixed Aryl Phosphonate Prodrugs. ChemMedChem 2019; 14:1597-1603. [PMID: 31226236 PMCID: PMC6726502 DOI: 10.1002/cmdc.201900344] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Indexed: 12/16/2022]
Abstract
A set of phosphonate prodrugs of a butyrophilin ligand was synthesized and evaluated for plasma stability and cellular activity. The mixed aryl acyloxy esters were prepared either via a standard sequence through the phosphonic acid chloride, or through the more recently reported, and more facile, triflate activation. In the best of cases, this class of prodrugs shows cellular potency similar to that of bis-acyloxyalkyl phosphonate prodrugs and plasma stability similar to that of aryl phosphonamidates. For example, {[((3E)-5-hydroxy-4-methylpent-3-en-1-yl) (naphthalen-2-yloxy)phosphoryl]oxy}methyl 2,2-dimethylpropanoate can activate BTN3A1 in K562 cells after just 15 minutes of exposure (at an EC50 value of 31 nm) and is only partially metabolized (60 % remaining) after 20 hours in human plasma. Other related novel analogues showed similar potency/stability profiles. Therefore, mixed aryl acyloxyalkyl phosphonate prodrugs are an exciting new strategy for the delivery of phosphonate-containing drugs.
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Affiliation(s)
- Benjamin J Foust
- Department of Chemistry, University of Iowa, E531 Chemistry Building, Iowa City, IA, 52242, USA
| | - Jin Li
- Department of Pharmaceutical Sciences, University of Connecticut, 69 North Eagleville Road, Unit 3092, Storrs, CT, 06269, USA
| | - Chia-Hung Christine Hsiao
- Department of Pharmaceutical Sciences, University of Connecticut, 69 North Eagleville Road, Unit 3092, Storrs, CT, 06269, USA
| | - David F Wiemer
- Department of Chemistry, University of Iowa, E531 Chemistry Building, Iowa City, IA, 52242, USA
| | - Andrew J Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, 69 North Eagleville Road, Unit 3092, Storrs, CT, 06269, USA
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11
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Poe MM, Agabiti SS, Liu C, Li V, Teske KA, Hsiao CHC, Wiemer AJ. Probing the Ligand-Binding Pocket of BTN3A1. J Med Chem 2019; 62:6814-6823. [PMID: 31268699 DOI: 10.1021/acs.jmedchem.9b00825] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Small-molecule phosphoantigens such as (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate stimulate human Vγ9Vδ2 T cells after binding to the intracellular B30.2 domain of the immune receptor butyrophilin 3 isoform A1 (BTN3A1). To understand the ligand-target interaction in greater detail, we performed molecular docking. Based on the docking results, we synthesized the novel ligand (E)-(7-hydroxy-6-methylhept-5-en-1-yl)phosphonate and mutated proposed binding site residues. We evaluated the impact on butyrophilin binding of existing and novel ligands using a newly developed high-throughput fluorescence polarization assay. We also evaluated the ability of the compounds to stimulate proliferation and interferon-γ production of Vγ9Vδ2 T cells. Mutation of H381 fully blocked ligand binding, whereas mutations to charged surface residues impacted diphosphate interactions. Monophosphonate analogs bind similarly to BTN3A1, although they differ in their antigenicity, demonstrating that binding and efficacy are not linearly correlated. These results further define the structure-activity relationships underlying BTN3A1 ligand binding and antigenicity and support further structure-guided drug design.
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Affiliation(s)
| | | | | | | | - Kelly A Teske
- Department of Chemistry , Western Michigan University , Kalamazoo , Michigan 49008 , United States
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12
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Lentini NA, Foust BJ, Hsiao CHC, Wiemer AJ, Wiemer DF. Phosphonamidate Prodrugs of a Butyrophilin Ligand Display Plasma Stability and Potent Vγ9 Vδ2 T Cell Stimulation. J Med Chem 2018; 61:8658-8669. [PMID: 30199251 PMCID: PMC6703555 DOI: 10.1021/acs.jmedchem.8b00655] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Small organophosphorus compounds stimulate Vγ9 Vδ2 T cells if they serve as ligands of butyrophilin 3A1. Because the most potent natural ligand is ( E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP), which is the last intermediate in bacterial biosynthesis of isoprenoids that is not found in mammalian metabolism, activation of these T cells represents an important component of the immune response to bacterial infections. To identify butyrophilin ligands that may have greater plasma stability, and clinical potential, we have prepared a set of aryl phosphonamidate derivatives (9a-i) of the natural ligand. Testing of these new compounds in assays of T cell response has revealed that this strategy can provide compounds with high potency for expansion of Vγ9 Vδ2 T cells (9f, EC50 = 340 pM) and interferon γ production in response to loaded K562 cells (9e, EC50 = 62 nM). Importantly, all compounds of this class display extended plasma stability ( t1/2 > 24 h). These findings increase our understanding of metabolism of butyrophilin ligands and the structure-activity relationships of phosphonamidate prodrugs.
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Affiliation(s)
- Nicholas A Lentini
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242-1294 , United States
| | - Benjamin J Foust
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242-1294 , United States
| | - Chia-Hung Christine Hsiao
- Department of Pharmaceutical Sciences , University of Connecticut , Storrs , Connecticut 06269-3092 , United States
| | - Andrew J Wiemer
- Department of Pharmaceutical Sciences , University of Connecticut , Storrs , Connecticut 06269-3092 , United States
- Institute for Systems Genomics , University of Connecticut , Storrs , Connecticut 06269-3092 , United States
| | - David F Wiemer
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242-1294 , United States
- Department of Pharmacology , University of Iowa , Iowa City , Iowa 52242-1109 , United States
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13
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Hoeres T, Smetak M, Pretscher D, Wilhelm M. Improving the Efficiency of Vγ9Vδ2 T-Cell Immunotherapy in Cancer. Front Immunol 2018; 9:800. [PMID: 29725332 PMCID: PMC5916964 DOI: 10.3389/fimmu.2018.00800] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/03/2018] [Indexed: 12/28/2022] Open
Abstract
Increasing immunological knowledge and advances in techniques lay the ground for more efficient and broader application of immunotherapies. gamma delta (γδ) T-cells possess multiple favorable anti-tumor characteristics, making them promising candidates to be used in cellular and combination therapies of cancer. They recognize malignant cells, infiltrate tumors, and depict strong cytotoxic and pro-inflammatory activity. Here, we focus on human Vγ9Vδ2 T-cells, the most abundant γδ T-cell subpopulation in the blood, which are able to inhibit cancer progression in various models in vitro and in vivo. For therapeutic use they can be cultured and manipulated ex vivo and in the following adoptively transferred to patients, as well as directly stimulated to propagate in vivo. In clinical studies, Vγ9Vδ2 T-cells repeatedly demonstrated a low toxicity profile but hitherto only the modest therapeutic efficacy. This review provides a comprehensive summary of established and newer strategies for the enhancement of Vγ9Vδ2 T-cell anti-tumor functions. We discuss data of studies exploring methods for the sensitization of malignant cells, the improvement of recognition mechanisms and cytotoxic activity of Vγ9Vδ2 T-cells. Main aspects are the tumor cell metabolism, antibody-dependent cell-mediated cytotoxicity, antibody constructs, as well as activating and inhibitory receptors like NKG2D and immune checkpoint molecules. Several concepts show promising results in vitro, now awaiting translation to in vivo models and clinical studies. Given the array of research and encouraging findings in this area, this review aims at optimizing future investigations, specifically targeting the unanswered questions.
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Affiliation(s)
- Timm Hoeres
- Department of Hematology and Medical Oncology, Paracelsus Medical University, Nuremberg, Germany
| | - Manfred Smetak
- Department of Hematology and Medical Oncology, Paracelsus Medical University, Nuremberg, Germany
| | - Dominik Pretscher
- Department of Hematology and Medical Oncology, Paracelsus Medical University, Nuremberg, Germany
| | - Martin Wilhelm
- Department of Hematology and Medical Oncology, Paracelsus Medical University, Nuremberg, Germany
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14
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Sevrain CM, Berchel M, Couthon H, Jaffrès PA. Phosphonic acid: preparation and applications. Beilstein J Org Chem 2017; 13:2186-2213. [PMID: 29114326 PMCID: PMC5669239 DOI: 10.3762/bjoc.13.219] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/19/2017] [Indexed: 12/26/2022] Open
Abstract
The phosphonic acid functional group, which is characterized by a phosphorus atom bonded to three oxygen atoms (two hydroxy groups and one P=O double bond) and one carbon atom, is employed for many applications due to its structural analogy with the phosphate moiety or to its coordination or supramolecular properties. Phosphonic acids were used for their bioactive properties (drug, pro-drug), for bone targeting, for the design of supramolecular or hybrid materials, for the functionalization of surfaces, for analytical purposes, for medical imaging or as phosphoantigen. These applications are covering a large panel of research fields including chemistry, biology and physics thus making the synthesis of phosphonic acids a determinant question for numerous research projects. This review gives, first, an overview of the different fields of application of phosphonic acids that are illustrated with studies mainly selected over the last 20 years. Further, this review reports the different methods that can be used for the synthesis of phosphonic acids from dialkyl or diaryl phosphonate, from dichlorophosphine or dichlorophosphine oxide, from phosphonodiamide, or by oxidation of phosphinic acid. Direct methods that make use of phosphorous acid (H3PO3) and that produce a phosphonic acid functional group simultaneously to the formation of the P-C bond, are also surveyed. Among all these methods, the dealkylation of dialkyl phosphonates under either acidic conditions (HCl) or using the McKenna procedure (a two-step reaction that makes use of bromotrimethylsilane followed by methanolysis) constitute the best methods to prepare phosphonic acids.
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Affiliation(s)
- Charlotte M Sevrain
- CEMCA UMR CNRS 6521, Université de Brest, IBSAM. 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Mathieu Berchel
- CEMCA UMR CNRS 6521, Université de Brest, IBSAM. 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Hélène Couthon
- CEMCA UMR CNRS 6521, Université de Brest, IBSAM. 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Paul-Alain Jaffrès
- CEMCA UMR CNRS 6521, Université de Brest, IBSAM. 6 Avenue Victor Le Gorgeu, 29238 Brest, France
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15
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Foust BJ, Poe MM, Lentini NA, Hsiao CHC, Wiemer AJ, Wiemer DF. Mixed Aryl Phosphonate Prodrugs of a Butyrophilin Ligand. ACS Med Chem Lett 2017; 8:914-918. [PMID: 28947936 DOI: 10.1021/acsmedchemlett.7b00245] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 08/09/2017] [Indexed: 02/08/2023] Open
Abstract
Studies of aryl phosphonate derivatives of a butyrophilin 3A1 ligand have resulted in identification of a potent stimulant of Vγ9 Vδ2 T cells. This compound, a mixed ester bearing one pivaloyloxymethyl substituent and one 1-naphthyl ester displayed an EC50 of 0.79 nM as a stimulant of T cell proliferation, and a 9.0 nM EC50 in an assay designed to measure interferon gamma production. In both assays, this is the most potent butyrophilin ligand prodrug yet reported, and thus it should be a valuable tool for studies of T cell function. Furthermore, mixed aryl/acyloxyalkyl esters may represent a new class of phosphonate prodrugs with high efficacy.
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Affiliation(s)
- Benjamin J. Foust
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Michael M. Poe
- Department
of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269-3092 United States
| | - Nicholas A. Lentini
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
| | - Chia-Hung Christine Hsiao
- Department
of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269-3092 United States
| | - Andrew J. Wiemer
- Department
of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269-3092 United States
- Institute
for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269-3092, United States
| | - David F. Wiemer
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242-1294, United States
- Department
of Pharmacology, University of Iowa, Iowa City, Iowa 52242-1109, United States
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16
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Xiang Z, Tu W. Dual Face of Vγ9Vδ2-T Cells in Tumor Immunology: Anti- versus Pro-Tumoral Activities. Front Immunol 2017; 8:1041. [PMID: 28894450 PMCID: PMC5581348 DOI: 10.3389/fimmu.2017.01041] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 08/11/2017] [Indexed: 12/31/2022] Open
Abstract
Vγ9Vδ2-T cells are considered as potent effector cells for tumor immunotherapy through directly killing tumor cells and indirectly regulating other innate and adaptive immune cells to establish antitumoral immunity. The antitumoral activity of Vγ9Vδ2-T cells is governed by a complicated set of activating and inhibitory cell receptors. In addition, cytokine milieu in tumor microenvironment can also induce the pro-tumoral activities and functional plasticity of Vγ9Vδ2-T cells. Here, we review the anti- versus pro-tumoral activities of Vγ9Vδ2-T cells and discuss the mechanisms underlying the recognition, activation, differentiation and regulation of Vγ9Vδ2-T cells in tumor immunosurveillance. The comprehensive understanding of the dual face of Vγ9Vδ2-T cells in tumor immunology may improve the therapeutic efficacy and clinical outcomes of Vγ9Vδ2-T cell-based tumor immunotherapy.
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Affiliation(s)
- Zheng Xiang
- Li Ka Shing Faculty of Medicine, Department of Paediatrics and Adolescent Medicine, Laboratory for Translational Immunology, University of Hong Kong, Hong Kong, Hong Kong
| | - Wenwei Tu
- Li Ka Shing Faculty of Medicine, Department of Paediatrics and Adolescent Medicine, Laboratory for Translational Immunology, University of Hong Kong, Hong Kong, Hong Kong
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17
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Nguyen K, Li J, Puthenveetil R, Lin X, Poe MM, Hsiao CHC, Vinogradova O, Wiemer AJ. The butyrophilin 3A1 intracellular domain undergoes a conformational change involving the juxtamembrane region. FASEB J 2017; 31:4697-4706. [PMID: 28705810 DOI: 10.1096/fj.201601370rr] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 06/27/2017] [Indexed: 12/23/2022]
Abstract
Small isoprenoid diphosphates, such as (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP), are ligands of the internal domain of BTN3A1. Ligand binding in target cells promotes activation of Vγ9Vδ2 T cells. We demonstrate by small-angle X-ray scattering (SAXS) that HMBPP binding to the internal domain of BTN3A1 induces a conformational change in the position of the B30.2 domain relative to the juxtamembrane (JM) region. To better understand the molecular details of this conformational rearrangement, NMR spectroscopy was used to discover that the JM region interacts with HMBPP, specifically at the diphosphate. The spectral location of the affected amide peaks, partial NMR assignments, and JM mutants (ST296AA or T304A) investigated, confirm that the backbone amide of at least one Thr (Thr304), adjacent to conserved Ser, comes close to the HMBPP diphosphate, whereas double mutation of nonconserved residues (Ser/Thr296/297) may perturb the local fold. Cellular mutation of either of the identified Thr residues reduces the activation of Vγ9Vδ2 T cells by HMBPP, zoledronate, and POM2-C-HMBP, but not by a partial agonist BTN3 antibody. Taken together, our results show that ligand binding to BTN3A1 induces a conformational change within the intracellular domain that involves the JM region and is required for full activation.-Nguyen, K., Li, J., Puthenveetil, R., Lin, X., Poe, M. M., Hsiao, C.-H. C., Vinogradova, O., Wiemer, A. J. The butyrophilin 3A1 intracellular domain undergoes a conformational change involving the juxtamembrane region.
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Affiliation(s)
- Khiem Nguyen
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Jin Li
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Robbins Puthenveetil
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Xiaochen Lin
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Michael M Poe
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | | | - Olga Vinogradova
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Andrew J Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA; .,Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut, USA
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18
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Shippy RR, Lin X, Agabiti SS, Li J, Zangari BM, Foust BJ, Poe MM, Hsiao CHC, Vinogradova O, Wiemer DF, Wiemer AJ. Phosphinophosphonates and Their Tris-pivaloyloxymethyl Prodrugs Reveal a Negatively Cooperative Butyrophilin Activation Mechanism. J Med Chem 2017; 60:2373-2382. [PMID: 28218845 DOI: 10.1021/acs.jmedchem.6b00965] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Butyrophilin 3A1 (BTN3A1) binds small phosphorus-containing molecules, which initiates transmembrane signaling and activates butyrophilin-responsive cells. We synthesized several phosphinophosphonates and their corresponding tris-pivaloyloxymethyl (tris-POM) prodrugs and examined their effects on BTN3A1. An analog of (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) bound to BTN3A1 with intermediate affinity, which was enthalpy-driven. Docking studies revealed binding to the basic surface pocket and interactions between the allylic hydroxyl group and the BTN3A1 backbone. The phosphinophosphonate stimulated proliferation of Vγ9Vδ2 T cells with moderate activity (EC50 = 26 μM). Cellular potency was enhanced >600-fold in the tris-POM prodrug (EC50 = 0.041 μM). The novel prodrug also induced T cell mediated leukemia cell lysis. Analysis of dose-response data reveals HMBPP-induced Hill coefficients of 0.69 for target cell lysis and 0.68 in interferon secretion. Together, tris-POM prodrugs enhance the cellular activity of phosphinophosphonates, reveal structure-activity relationships of butyrophilin ligands, and support a negatively cooperative model of cellular butyrophilin activation.
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Affiliation(s)
- Rebekah R Shippy
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Xiaochen Lin
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Sherry S Agabiti
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Jin Li
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Brendan M Zangari
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Benjamin J Foust
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Michael M Poe
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Chia-Hung Christine Hsiao
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - Olga Vinogradova
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States
| | - David F Wiemer
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Andrew J Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut , Storrs, Connecticut 06269, United States.,Institute for Systems Genomics, University of Connecticut , Storrs, Connecticut 06269, United States
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19
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Kilcollins AM, Li J, Hsiao CHC, Wiemer AJ. HMBPP Analog Prodrugs Bypass Energy-Dependent Uptake To Promote Efficient BTN3A1-Mediated Malignant Cell Lysis by Vγ9Vδ2 T Lymphocyte Effectors. THE JOURNAL OF IMMUNOLOGY 2016; 197:419-28. [PMID: 27271567 DOI: 10.4049/jimmunol.1501833] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 05/04/2016] [Indexed: 01/05/2023]
Abstract
Vγ9Vδ2 effector T cells lyse cells in response to phosphorus-containing small molecules, providing primates a unique route to remove infected or malignant cells. Yet, the triggering mechanisms remain ill defined. We examined lysis mediated by human Vγ9Vδ2 effector T cells in response to the naturally occurring (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) or a synthetic cell-permeable prodrug, bis (pivaloyloxymethyl) (E)-4-hydroxy-3-methyl-but-2-enyl phosphonate. CD27(+)/CD45RA(-) Th1-like effector cells killed K562 target cells through a mechanism that could be enhanced by either compound or TCR Ab and blocked by Src inhibition or butyrophilin 3 isoform A1 (BTN3A1) disruption. Pretreatment at 4 °: C decreased HMBPP-induced lysis but did not reduce lysis induced by bis (pivaloyloxymethyl) (E)-4-hydroxy-3-methyl-but-2-enyl phosphonate. Together, our results show that internalization of HMBPP into target cells is required for BTN3A1-dependent lysis by Vγ9Vδ2 effector T cells. The enhanced activity of the prodrug analog is due to its ability to bypass the pathways required for entry of HMBPP. These findings support an inside-out model of T cell triggering driven by small-molecule induction of BTN3A1.
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Affiliation(s)
- Ashley M Kilcollins
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT 06269
| | - Jin Li
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269; and
| | | | - Andrew J Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269; and Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269
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20
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Alguacil J, Reyes D, Aubin Y, Roy B, Périgaud C, Champagne E, Peyrottes S. Exploring synthetic pathways for nucleosidic derivatives of potent phosphoantigens. NEW J CHEM 2016. [DOI: 10.1039/c5nj03614c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Wiemer AJ, Shippy RR, Kilcollins AM, Li J, Hsiao CHC, Barney RJ, Geng ML, Wiemer DF. Evaluation of a 7-Methoxycoumarin-3-carboxylic Acid Ester Derivative as a Fluorescent, Cell-Cleavable, Phosphonate Protecting Group. Chembiochem 2015; 17:52-5. [PMID: 26503489 DOI: 10.1002/cbic.201500484] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Indexed: 02/04/2023]
Abstract
Cell-cleavable protecting groups often enhance cellular delivery of species that are charged at physiological pH. Although several phosphonate protecting groups have achieved clinical success, it remains difficult to use these prodrugs in live cells to clarify biological mechanisms. Here, we present a strategy that uses a 7-methoxycoumarin-3-carboxylic acid ester as a fluorescent protecting group. This strategy was applied to synthesis of an (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) analogue to assess cellular uptake and human Vγ9Vδ2 T cell activation. The fluorescent ester displayed low cellular toxicity (IC50 >100 μm) and strong T cell activation (EC50 =0.018 μm) relative to the unprotected anion (EC50 =23 μm). The coumarin-derived analogue allowed no-wash analysis of biological deprotection, which revealed rapid internalization of the prodrug. These results demonstrate that fluorescent groups can be applied both as functional drug delivery tools and useful biological probes of drug uptake.
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Affiliation(s)
- Andrew J Wiemer
- Department of Pharmaceutical Sciences, Institute for Systems Genomics, University of Connecticut, 69 N. Eagleville Rd Unit 3092, Storrs, CT, 06269, USA
| | - Rebekah R Shippy
- Department of Chemistry, University of Iowa, E531 Chemistry Building, Iowa City, IA, 52242, USA
| | - Ashley M Kilcollins
- Department of Physiology and Neurobiology, University of Connecticut, 75 N. Eagleville Rd Unit 3156, Storrs, CT, 06269, USA
| | - Jin Li
- Department of Pharmaceutical Sciences, Institute for Systems Genomics, University of Connecticut, 69 N. Eagleville Rd Unit 3092, Storrs, CT, 06269, USA
| | - Chia-Hung Christine Hsiao
- Department of Pharmaceutical Sciences, Institute for Systems Genomics, University of Connecticut, 69 N. Eagleville Rd Unit 3092, Storrs, CT, 06269, USA
| | - Rocky J Barney
- Department of Chemistry, Western Wyoming Community College, 1204-A, Rock Springs, WY, 82901, USA
| | - M Lei Geng
- Department of Chemistry, Optical Science and Technology Center, University of Iowa, 330 IATL, Iowa City, IA, 52242, USA
| | - David F Wiemer
- Department of Chemistry, University of Iowa, E531 Chemistry Building, Iowa City, IA, 52242, USA.
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22
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Phosphoantigen Burst upon Plasmodium falciparum Schizont Rupture Can Distantly Activate Vγ9Vδ2 T Cells. Infect Immun 2015; 83:3816-24. [PMID: 26169273 PMCID: PMC4567633 DOI: 10.1128/iai.00446-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 07/07/2015] [Indexed: 11/23/2022] Open
Abstract
Malaria induces potent activation and expansion of the Vγ9Vδ2 subpopulation of γδT cells, which inhibit the Plasmodium falciparum blood cycle through soluble cytotoxic mediators, abrogating merozoite invasion capacity. Intraerythrocytic stages efficiently trigger Vγ9Vδ2 T-cell activation and degranulation through poorly understood mechanisms. P. falciparum blood-stage extracts are known to contain phosphoantigens able to stimulate Vγ9Vδ2 T cells, but how these are presented by intact infected red blood cells (iRBCs) remains elusive. Here we show that, unlike activation by phosphoantigen-expressing cells, Vγ9Vδ2 T-cell activation by intact iRBCs is independent of butyrophilin expression by the iRBC, and contact with an intact iRBC is not required. Moreover, blood-stage culture supernatants proved to be as potent activators of Vγ9Vδ2 T cells as iRBCs. Bioactivity in the microenvironment is attributable to phosphoantigens, as it is dependent on the parasite DOXP pathway, on Vγ9Vδ2 TCR signaling, and on butyrophilin expression by Vγ9Vδ2 T cells. Kinetic studies showed that the phosphoantigens were released at the end of the intraerythrocytic cycle at the time of parasite egress. We document exquisite sensitivity of Vγ9Vδ2 T cells, which respond to a few thousand parasites. These data unravel a novel framework, whereby release of phosphoantigens into the extracellular milieu by sequestered parasites likely promotes activation of distant Vγ9Vδ2 T cells that in turn exert remote antiparasitic functions.
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23
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Hsiao CHC, Lin X, Barney RJ, Shippy RR, Li J, Vinogradova O, Wiemer DF, Wiemer AJ. Synthesis and Biological Evaluation of a Phosphonate Phosphoantigen Prodrug. PHOSPHORUS SULFUR 2015. [DOI: 10.1080/10426507.2014.974099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
| | - Xiaochen Lin
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Rocky J. Barney
- Department of Chemistry, University of Iowa, Iowa City, Iowa, USA
- Department of Chemistry, Western Wyoming Community College, Rock Springs, Wyoming, USA
| | | | - Jin Li
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - Olga Vinogradova
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | - David F. Wiemer
- Department of Chemistry, University of Iowa, Iowa City, Iowa, USA
- Department of Pharmacology, University of Iowa, Iowa City, Iowa, USA
| | - Andrew J. Wiemer
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
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24
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De Libero G, Lau SY, Mori L. Phosphoantigen Presentation to TCR γδ Cells, a Conundrum Getting Less Gray Zones. Front Immunol 2015; 5:679. [PMID: 25642230 PMCID: PMC4295553 DOI: 10.3389/fimmu.2014.00679] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 12/16/2014] [Indexed: 01/02/2023] Open
Abstract
The mechanistic requirements of antigen recognition by T cells expressing a γδ TCR has revealed important differences with those of αβ TCR cells and, despite impressive new data generated in the very recent years, they remain poorly understood. Based on the structure of the TCR chains and the tissue distribution, γδ cells are represented in a variety of populations. The major subset of human peripheral blood γδ cells express Vγ9Vδ2 TCR heterodimers and are all stimulated by phosphorylated metabolites (commonly called phosphoantigens). Phosphoantigens are molecules with a very small mass and only stimulate Vγ9Vδ2 cells in the presence of antigen-presenting cells, suggesting a strict requirement for dedicated antigen-presenting molecules. Recent studies have identified butyrophilin (BTN) 3A1 as the molecule necessary to stimulate Vγ9Vδ2 cells. BTN3A1 extracellular, transmembrane, and cytoplasmic domains have different functions, including cognate interaction with the Vγ9Vδ2 TCR, binding of the phosphoantigens, and interaction with cytoplasmic proteins. This review mainly discusses the known molecular mechanisms of BTN3A1-mediated antigen presentation to γδ cells and proposes a model of phosphoantigen presentation, which integrates past and recent studies.
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Affiliation(s)
- Gennaro De Libero
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR) , Singapore , Singapore ; Department of Biomedicine, University of Basel , Basel , Switzerland
| | - Sze-Yi Lau
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR) , Singapore , Singapore
| | - Lucia Mori
- Singapore Immunology Network, Agency for Science, Technology and Research (ASTAR) , Singapore , Singapore ; Department of Biomedicine, University of Basel , Basel , Switzerland
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25
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Hsiao CH, Lin X, Barney R, Shippy R, Li J, Vinogradova O, Wiemer D, Wiemer A. Synthesis of a Phosphoantigen Prodrug that Potently Activates Vγ9Vδ2 T-Lymphocytes. ACTA ACUST UNITED AC 2014; 21:945-54. [DOI: 10.1016/j.chembiol.2014.06.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 06/12/2014] [Accepted: 06/18/2014] [Indexed: 12/31/2022]
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