1
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Zhang RY, Wen Y, He CB, Zhou SH, Wu YH, Wang EY, Feng RR, Ding D, Du JJ, Gao XF, Guo J. Conjugation of TLR7 and TLR7/8 agonists onto weak protein antigen via versatile oxime ligation for enhanced vaccine efficacy. Int J Biol Macromol 2024; 278:134620. [PMID: 39127274 DOI: 10.1016/j.ijbiomac.2024.134620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 08/07/2024] [Accepted: 08/07/2024] [Indexed: 08/12/2024]
Abstract
Protein-based subunit vaccines are weakly immunogenic, and developing self-adjuvanting vaccines with adjuvant conjugated to antigen is a promising approach for generating optimal immune responses. Here, we report a novel adjuvant-protein conjugate vaccine based on versatile oxime ligation technique. Firstly, the adjuvant properties of a series of TLR7 and TLR7/8 small molecule agonists in self-adjuvanting vaccines were systematically compared by coupling them to proteins in consistent ratio via p-carboxybenzaldehyde (p-CBA) for the first time. All conjugate vaccines induced cytokine secretion in murine and human macrophages in vitro, and promoted specific antibody production in vivo. Notably, a conjugate containing imidazoquinoline TLR7/8 agonist (TLR7/8a1) showed the greatest enhancement in Th1/2 balanced antibody response. To minimize the interference with the protein antigenic integrity, we further developed a systematic glycoconjugation strategy to conjugate this TLR7/8a1 onto the glycan chains of SARS-CoV-2 S1 glycoprotein via oxime ligation, in which S1 containing different numbers of aldehyde groups were obtained by differential periodate oxidation. The resulting TLR7/8a1-S1 conjugate triggered a potent humoral and cellular immunity in vivo. Together these data demonstrate the promise of these TLR7 and TLR7/8 agonists as effective built-in adjuvants, and the versatile oxime ligation strategy might broaden potential applications in designing different conjugate vaccines.
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Affiliation(s)
- Ru-Yan Zhang
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China; Hubei Key Laboratory of Kidney Disease Pathogenesis and Intervention, College of Medicine, Hubei Polytechnic University, Huangshi 435003, China
| | - Yu Wen
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Chen-Bin He
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Shi-Hao Zhou
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Ye-Hui Wu
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - En-Yang Wang
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Ran-Ran Feng
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Dong Ding
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Jing-Jing Du
- Hubei Key Laboratory of Kidney Disease Pathogenesis and Intervention, College of Medicine, Hubei Polytechnic University, Huangshi 435003, China
| | - Xiao-Fei Gao
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, School of Chemistry and Materials Science, East China University of Technology, Nanchang 330013, China
| | - Jun Guo
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, China.
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2
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Thanvi R, Nada S, Dissanayake R, Vartak A, Sebilleau CO, Alom NE, Prestwich EG, Wall KA, Sucheck SJ. Synthesis and Evaluation of a Self-Adjuvanting Pseudomonal Vaccine Based on Major Outer Membrane Porin OprF Epitopes Formulated with Low-Toxicity QS-21-Containing Liposomes. Bioconjug Chem 2023; 34:893-910. [PMID: 37092892 PMCID: PMC10723056 DOI: 10.1021/acs.bioconjchem.3c00103] [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] [Indexed: 04/25/2023]
Abstract
Pseudomonas aeruginosa (PA) is a Gram-negative pathogen that the World Health Organization has ranked as a priority 1 (critical) threat. One potential prophylactic approach to preventing or reducing the incidence of PA would be development of a long sought-after vaccine. Both antibody and CD4+ T-cell responses have been noted as playing key roles in protection against infection. In these studies, we have designed a prototype vaccine consisting of several known linear B-cell epitopes derived from an outer membrane porin F (OprF). The resulting thiol-containing protein was conjugated to a version of the lipopeptide-based Toll-like receptor agonist Pam3CysSK4Mal (10) containing a maleimide moiety and formulated into dipalmitoylphosphatidylcholine (DPPC)/cholesterol (Chol) liposomes. Mice immunized with the resulting vaccine generated antibodies that bound PA14 (serotype O10) in vitro and induced opsonization in the presence of rabbit complement and murine macrophage RAW264.7 cells. The liposome was optimized to contain 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dimyristoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DMPG), Chol, Pam3CysSK4-OprF (12) and the Quillaja saponaria-derived saponin adjuvant QS-21. The resulting vaccine formulation produced significantly higher antibody titers, increased the IgG2a antibody isotype, and increased the number of IgG-producing B-cells as well as splenic primed T-cells. In summary, the liposomal vaccine platform was found highly useful for the generation of a robust and balanced TH1/TH2 response.
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Affiliation(s)
- Radhika Thanvi
- Department of Chemistry and Biochemistry, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Shadia Nada
- Department of Medicinal and Biological Chemistry, University of Toledo, Toledo, Ohio 43614, United States
| | - Ravindika Dissanayake
- Department of Medicinal and Biological Chemistry, University of Toledo, Toledo, Ohio 43614, United States
| | - Abhishek Vartak
- Department of Chemistry and Biochemistry, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Chloé Olayinka Sebilleau
- Department of Chemistry and Biochemistry, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Nur-E Alom
- Department of Chemistry and Biochemistry, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Erin G Prestwich
- Department of Medicinal and Biological Chemistry, University of Toledo, Toledo, Ohio 43614, United States
| | - Katherine A Wall
- Department of Medicinal and Biological Chemistry, University of Toledo, Toledo, Ohio 43614, United States
| | - Steven J Sucheck
- Department of Chemistry and Biochemistry, University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
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3
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Built-in adjuvants for use in vaccines. Eur J Med Chem 2022; 227:113917. [PMID: 34688011 DOI: 10.1016/j.ejmech.2021.113917] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/30/2021] [Accepted: 10/09/2021] [Indexed: 02/08/2023]
Abstract
Vaccine refers to biological products that are produced using various pathogenic microorganisms for inoculation. The goal of vaccination is to induce a robust immune response against a specific antigen, thus preventing the organism from getting infected. In vaccines, adjuvants have been widely employed to enhance immunity against specific antigens. An ideal adjuvant should be stable, biodegradable, and low cost, not induce system rejection and promote an immune response. Various adjuvant components have been investigated across diverse applications. Typically, adjuvants are employed to meet the following objectives: (1) to improve the effectiveness of immunization with vaccines for specific populations, such as newborns and the elderly; (2) enhance the immunogenicity of highly purified or recombinant antigens; (3) allow immunization with a smaller dose of the vaccine, reducing drug dosage. In the present review, we primarily focus on chemically synthesized compounds that can be used as built-in adjuvants. We elaborate the classification of these compounds based on the induced immune activation mechanism and summarize their application in various vaccine types.
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4
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De Vrieze J, Baptista AP, Nuhn L, Van Herck S, Deswarte K, Yu H, Lambrecht BN, De Geest BG. Lipid Nature and Alkyl Length Influence Lymph Node Accumulation of Lipid‐Polyethylene Glycol Amphiphiles. ADVANCED THERAPEUTICS 2021. [DOI: 10.1002/adtp.202100079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jana De Vrieze
- Department of Pharmaceutics Ghent University Ottergemsesteenweg 460 Ghent 9000 Belgium
| | - Antonio P. Baptista
- Laboratory of Immunoregulation and Mucosal Immunology VIB‐UGhent Center for Inflammation Research Technologiepark‐Zwijnaarde 71 Ghent 9052 Belgium
- Department of Internal Medicine and Pediatrics Ghent University C. Heymanslaan 10 Ghent 9000 Belgium
| | - Lutz Nuhn
- Max Planck Institute for Polymer Research Ackermannweg 10 Mainz 55128 Germany
| | - Simon Van Herck
- Department of Pharmaceutics Ghent University Ottergemsesteenweg 460 Ghent 9000 Belgium
| | - Kim Deswarte
- Laboratory of Immunoregulation and Mucosal Immunology VIB‐UGhent Center for Inflammation Research Technologiepark‐Zwijnaarde 71 Ghent 9052 Belgium
- Department of Internal Medicine and Pediatrics Ghent University C. Heymanslaan 10 Ghent 9000 Belgium
| | - Haijun Yu
- State Key Laboratory of Drug Research & Center of Pharmaceutics Shanghai Institute of Materia Medica Chinese Academy of Sciences 555 Zu Chong Zhi Road Shanghai 201203 China
| | - Bart N. Lambrecht
- Laboratory of Immunoregulation and Mucosal Immunology VIB‐UGhent Center for Inflammation Research Technologiepark‐Zwijnaarde 71 Ghent 9052 Belgium
- Department of Internal Medicine and Pediatrics Ghent University C. Heymanslaan 10 Ghent 9000 Belgium
- Department of Pulmonary Medicine Erasmus University Medical Center Dr. Molewaterplein 40 Rotterdam 3015 GD Netherlands
| | - Bruno G. De Geest
- Department of Pharmaceutics Ghent University Ottergemsesteenweg 460 Ghent 9000 Belgium
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5
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Talukdar A, Ganguly D, Roy S, Das N, Sarkar D. Structural Evolution and Translational Potential for Agonists and Antagonists of Endosomal Toll-like Receptors. J Med Chem 2021; 64:8010-8041. [PMID: 34107682 DOI: 10.1021/acs.jmedchem.1c00300] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Toll-like receptors (TLRs) are members of a large family of evolutionarily conserved pattern recognition receptors (PRRs), which serve as key components of the innate immune system by playing a pivotal role in sensing "nonself" ligands. Endosomal TLRs (TLR3, TLR7, TLR8, and TLR9) can recognize pathogen-derived nucleic acid and initiate an innate immune response because they react against both self- and non-self-origin nucleic acid molecules. Accordingly, both receptor agonists and antagonists are potentially useful in disparate clinical contexts and thus are globally sought after. Recent research has revealed that agonists and antagonists share an overlapping binding region. This Perspective highlights rational medicinal chemistry approaches to elucidate the structural attributes of small molecules capable of agonism or antagonism or of elegantly switching between the two. The structural evolution of different chemotypes can provide the framework for the future development of endosomal TLR agonists and antagonists.
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Affiliation(s)
- Arindam Talukdar
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Dipyaman Ganguly
- IICB-Translational Research Unit of Excellence, Department of Cancer Biology and Inflammatory Disorders, CSIR-Indian Institute of Chemical Biology, CN6, Sector V, Salt Lake, Kolkata 700091, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Swarnali Roy
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Nirmal Das
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Dipika Sarkar
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
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Massena CJ, Lathrop SK, Davison CJ, Schoener R, Bazin HG, Evans JT, Burkhart DJ. A tractable covalent linker strategy for the production of immunogenic antigen-TLR7/8L bioconjugates. Chem Commun (Camb) 2021; 57:4698-4701. [PMID: 33977971 PMCID: PMC9118693 DOI: 10.1039/d1cc00795e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Despite the ease of production and improved safety profiles of recombinant vaccines, the inherently low immunogenicity of unadjuvanted proteins remains an impediment to their widespread adoption. The covalent tethering of TLR agonists to antigenic proteins offers a unique approach to co-deliver both constituents to the same cell-enhancing vaccine efficacy while minimizing reactogenicity. However, the paucity of simple and effective linker chemistries continues to hamper progress. Here, we present a modular, PEG-based linker system compatible with even extremely lipophilic and challenging TLR7/8 agonists. To advance the field and address previous obstacles, we offer the most straightforward and antigen-preserving linker system to date. These antigen-adjuvant conjugates enhance antigen-specific immune responses in mice, demonstrating the power of our approach within the context of modern vaccinology.
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Affiliation(s)
- C J Massena
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - S K Lathrop
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - C J Davison
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - R Schoener
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - H G Bazin
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - J T Evans
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
| | - D J Burkhart
- Dept. of Biomedical & Pharmaceutical Sciences, University of Montana, 32 Campus Dr, Missoula, MT 59812, USA.
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7
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Bolli E, Scherger M, Arnouk SM, Pombo Antunes AR, Straßburger D, Urschbach M, Stickdorn J, De Vlaminck K, Movahedi K, Räder HJ, Hernot S, Besenius P, Van Ginderachter JA, Nuhn L. Targeted Repolarization of Tumor-Associated Macrophages via Imidazoquinoline-Linked Nanobodies. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004574. [PMID: 34026453 PMCID: PMC8132149 DOI: 10.1002/advs.202004574] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/14/2021] [Indexed: 05/06/2023]
Abstract
Tumor-associated macrophages (TAMs) promote the immune suppressive microenvironment inside tumors and are, therefore, considered as a promising target for the next generation of cancer immunotherapies. To repolarize their phenotype into a tumoricidal state, the Toll-like receptor 7/8 agonist imidazoquinoline IMDQ is site-specifically and quantitatively coupled to single chain antibody fragments, so-called nanobodies, targeting the macrophage mannose receptor (MMR) on TAMs. Intravenous injection of these conjugates result in a tumor- and cell-specific delivery of IMDQ into MMRhigh TAMs, causing a significant decline in tumor growth. This is accompanied by a repolarization of TAMs towards a pro-inflammatory phenotype and an increase in anti-tumor T cell responses. Therefore, the therapeutic benefit of such nanobody-drug conjugates may pave the road towards effective macrophage re-educating cancer immunotherapies.
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Affiliation(s)
- Evangelia Bolli
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | | | - Sana M. Arnouk
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | - Ana Rita Pombo Antunes
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | - David Straßburger
- Department of ChemistryJohannes Gutenberg‐University MainzDuesbergweg 10‐14Mainz55128Germany
| | - Moritz Urschbach
- Department of ChemistryJohannes Gutenberg‐University MainzDuesbergweg 10‐14Mainz55128Germany
| | - Judith Stickdorn
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
| | - Karen De Vlaminck
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | - Kiavash Movahedi
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | - Hans Joachim Räder
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
| | - Sophie Hernot
- Laboratory of In Vivo Cellular and Molecular ImagingVrije Universiteit BrusselLaarbeeklaan 103Brussels1090Belgium
| | - Pol Besenius
- Department of ChemistryJohannes Gutenberg‐University MainzDuesbergweg 10‐14Mainz55128Germany
| | - Jo A. Van Ginderachter
- Lab of Cellular and Molecular ImmunologyVrije Universiteit BrusselPleinlaan 2Brussels1050Belgium
- Myeloid Cell Immunology LabVIB Center for Inflammation ResearchBrussels1050Belgium
| | - Lutz Nuhn
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
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8
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Short KK, Miller SM, Walsh L, Cybulski V, Bazin H, Evans JT, Burkhart D. Co-encapsulation of synthetic lipidated TLR4 and TLR7/8 agonists in the liposomal bilayer results in a rapid, synergistic enhancement of vaccine-mediated humoral immunity. J Control Release 2019; 315:186-196. [PMID: 31654684 PMCID: PMC6980726 DOI: 10.1016/j.jconrel.2019.10.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/11/2022]
Abstract
To increase vaccine immunogenicity, modern vaccines incorporate adjuvants, which serve to enhance immune cross-protection, improve humoral and cell-mediated immunity, and promote antigen dose sparing. Pattern recognition receptors (PRRs), including the Toll-like receptor (TLR) family are promising targets for development of agonist formulations for use as vaccine adjuvants. Combinations of co-delivered TLR4 and TLR7/8 ligands have been demonstrated to have synergistic effects on innate and adaptive immune response. Here, we create liposomes that stably co-encapsulate CRX-601, a synthetic TLR4 agonist, and UM-3004, a lipidated TLR7/8 agonist, within the liposomal bilayer in order to achieve co-delivery, allow tunable physical properties, and induce in vitro and in vivo immune synergy. Co-encapsulation demonstrates a synergistic increase in IL-12p70 cytokine output in vitro from treated human peripheral blood mononuclear cells (hPBMCs). Further, co-encapsulated formulations give significant improvement of early IgG2a antibody titers in BALB/c mice following primary vaccination when compared to single agonist or dual agonists delivered in separate liposomes. This work demonstrates that co-encapsulation of TLR4 and lipidated TLR7/8 agonists within the liposomal bilayer leads to innate and adaptive immune synergy which biases a Th1 immune response. Thus, liposomal co-encapsulation may be a useful and flexible tool for vaccine adjuvant formulation containing multiple TLR agonists.
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Affiliation(s)
- Kristopher K Short
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, USA
| | - Shannon M Miller
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Lois Walsh
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, USA
| | - Van Cybulski
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Hélène Bazin
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, USA
| | - Jay T Evans
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - David Burkhart
- Center for Translational Medicine, University of Montana, Missoula, MT 59812, USA; Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT 59812, USA.
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9
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Chan M, Lao FS, Chu PJ, Shpigelman J, Yao S, Nan J, Sato-Kaneko F, Li V, Hayashi T, Corr M, Carson DA, Cottam HB, Shukla NM. Structure–Activity Relationship Studies To Identify Affinity Probes in Bis-aryl Sulfonamides That Prolong Immune Stimuli. J Med Chem 2019; 62:9521-9540. [DOI: 10.1021/acs.jmedchem.9b00870] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Michael Chan
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Fitzgerald S. Lao
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Paul J. Chu
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Jonathan Shpigelman
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Shiyin Yao
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Jason Nan
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Fumi Sato-Kaneko
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Vicky Li
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Tomoko Hayashi
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Maripat Corr
- Department of Medicine, University of California, San Diego, La Jolla, California 92093, United States
| | - Dennis A. Carson
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Howard B. Cottam
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
| | - Nikunj M. Shukla
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093-0695, United States
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10
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Evans JT, Bess LS, Mwakwari SC, Livesay MT, Li Y, Cybulski V, Johnson DA, Bazin HG. Synthetic Toll-like Receptors 7 and 8 Agonists: Structure-Activity Relationship in the Oxoadenine Series. ACS OMEGA 2019; 4:15665-15677. [PMID: 31572869 PMCID: PMC6761749 DOI: 10.1021/acsomega.9b02138] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 08/27/2019] [Indexed: 05/08/2023]
Abstract
Toll-like receptors 7 and 8 (TLR7/8) are broadly expressed on antigen-presenting cells, making TLR7/8 agonists likely candidates for the development of new vaccine adjuvants. We previously reported the synthesis of a new series of 8-oxoadenines substituted at the 9-position with a 4-piperidinylalkyl moiety and demonstrated that TLR7/8 selectivity and potency could be modulated by varying the length of the alkyl linker. In the present study, we broadened our initial structure-activity relationship study to further evaluate the effects of N-heterocycle ring size, chirality, and substitution on TLR7/8 potency, receptor selectivity, and cytokine (IFNα and TNFα) induction from human peripheral blood mononuclear cells (PBMCs). TLR7/8 activity correlated primarily to linker length and to a lesser extent to ring size, while ring chirality had little effect on TLR7/8 potency or selectivity. Substitution of the heterocyclic ring with an aminoalkyl or hydroxyalkyl group for subsequent conjugation to phospholipids or antigens was well tolerated with the retention of both TLR7/8 activity and cytokine induction from human PBMCs.
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Affiliation(s)
- Jay T. Evans
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
- Division of Biological Sciences and Department of Biomedical and Pharmaceutical
Sciences, University of Montana, Missoula, Montana 59802, United States
| | - Laura S. Bess
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
- Division of Biological Sciences and Department of Biomedical and Pharmaceutical
Sciences, University of Montana, Missoula, Montana 59802, United States
| | - Sandra C. Mwakwari
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
| | - Mark T. Livesay
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
- Division of Biological Sciences and Department of Biomedical and Pharmaceutical
Sciences, University of Montana, Missoula, Montana 59802, United States
| | - Yufeng Li
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
| | - Van Cybulski
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
- Division of Biological Sciences and Department of Biomedical and Pharmaceutical
Sciences, University of Montana, Missoula, Montana 59802, United States
| | - David A. Johnson
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
| | - Hélène G. Bazin
- GSK
Vaccines, 553 Old Corvallis
Road, Hamilton, Montana 59840, United States
- Division of Biological Sciences and Department of Biomedical and Pharmaceutical
Sciences, University of Montana, Missoula, Montana 59802, United States
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11
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Lynn GM, Chytil P, Francica JR, Lagová A, Kueberuwa G, Ishizuka AS, Zaidi N, Ramirez-Valdez RA, Blobel NJ, Baharom F, Leal J, Wang AQ, Gerner MY, Etrych T, Ulbrich K, Seymour LW, Seder RA, Laga R. Impact of Polymer-TLR-7/8 Agonist (Adjuvant) Morphology on the Potency and Mechanism of CD8 T Cell Induction. Biomacromolecules 2019; 20:854-870. [PMID: 30608149 DOI: 10.1021/acs.biomac.8b01473] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Small molecule Toll-like receptor-7 and -8 agonists (TLR-7/8a) can be used as vaccine adjuvants to induce CD8 T cell immunity but require formulations that prevent systemic toxicity and focus adjuvant activity in lymphoid tissues. Here, we covalently attached TLR-7/8a to polymers of varying composition, chain architecture and hydrodynamic behavior (∼300 nm submicrometer particles, ∼10 nm micelles and ∼4 nm flexible random coils) and evaluated how these parameters of polymer-TLR-7/8a conjugates impact adjuvant activity in vivo. Attachment of TLR-7/8a to any of the polymer compositions resulted in a nearly 10-fold reduction in systemic cytokines (toxicity). Moreover, both lymph node cytokine production and the magnitude of CD8 T cells induced against protein antigen increased with increasing polymer-TLR-7/8a hydrodynamic radius, with the submicrometer particle inducing the highest magnitude responses. Notably, CD8 T cell responses induced by polymer-TLR-7/8a were dependent on CCR2+ monocytes and IL-12, whereas responses by a small molecule TLR-7/8a that unexpectedly persisted in vaccine-site draining lymph nodes (T1/2 = 15 h) had less dependence on monocytes and IL-12 but required Type I IFNs. This study shows how modular properties of synthetic adjuvants can be chemically programmed to alter immunity in vivo through distinct immunological mechanisms.
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Affiliation(s)
- Geoffrey M Lynn
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Petr Chytil
- Institute of Macromolecular Chemistry, Czech Academy of Sciences , Heyrovského nám. 2 , 162 06 Prague 6 , Czech Republic
| | - Joseph R Francica
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Anna Lagová
- Department of Oncology , University of Oxford , Old Road Campus Research Building , Oxford OX3 7DQ , United Kingdom
| | - Gray Kueberuwa
- Department of Oncology , University of Oxford , Old Road Campus Research Building , Oxford OX3 7DQ , United Kingdom
| | - Andrew S Ishizuka
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Neeha Zaidi
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Ramiro A Ramirez-Valdez
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Nicolas J Blobel
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Faezzah Baharom
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Joseph Leal
- Department of Immunology , University of Washington , South Lake Union E-411, 750 Republican Street , Seattle , Washington 98109 , United States
| | - Amy Q Wang
- Therapeutics for Rare and Neglected Diseases, National Center for Advancing Translational Sciences , 9800 Medical Center Drive , Rockville , Maryland 20850 , United States
| | - Michael Y Gerner
- Department of Immunology , University of Washington , South Lake Union E-411, 750 Republican Street , Seattle , Washington 98109 , United States
| | - Tomáš Etrych
- Institute of Macromolecular Chemistry, Czech Academy of Sciences , Heyrovského nám. 2 , 162 06 Prague 6 , Czech Republic
| | - Karel Ulbrich
- Institute of Macromolecular Chemistry, Czech Academy of Sciences , Heyrovského nám. 2 , 162 06 Prague 6 , Czech Republic
| | - Leonard W Seymour
- Department of Oncology , University of Oxford , Old Road Campus Research Building , Oxford OX3 7DQ , United Kingdom
| | - Robert A Seder
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases , National Institutes of Health, 40 Convent Drive , Bethesda , Maryland 20892 , United States
| | - Richard Laga
- Institute of Macromolecular Chemistry, Czech Academy of Sciences , Heyrovského nám. 2 , 162 06 Prague 6 , Czech Republic
- Department of Oncology , University of Oxford , Old Road Campus Research Building , Oxford OX3 7DQ , United Kingdom
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12
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Gupta CL, Babu Khan M, Ampasala DR, Akhtar S, Dwivedi UN, Bajpai P. Pharmacophore-based virtual screening approach for identification of potent natural modulatory compounds of human Toll-like receptor 7. J Biomol Struct Dyn 2019; 37:4721-4736. [PMID: 30661449 DOI: 10.1080/07391102.2018.1559098] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Toll-like receptor 7 (TLR7) is a transmembrane glycoprotein playing very crucial role in the signaling pathways involved in innate immunity and has been demonstrated to be useful in fighting against infectious disease by recognizing viral ssRNA & specific small molecule agonists. In order to find novel human TLR7 (hTLR7) modulators, computational ligand-based pharmacophore modeling approach was used to identify the molecular chemical features required for the modulation of hTLR7 protein. A training set of 20 TLR7 agonists with their known experimental activity was used to create pharmacophore model using 3D-QSAR pharmacophore generation (HypoGen algorithm) module in Discovery Studio. The best developed hypothesis consists of four pharmacophoric features namely, one hydrogen bond donor (HBD), one ring aromatic (RA), and two hydrophobic (HY) character. The developed hypothesis was then validated by different methods such as cost analysis, test set method, and Fischer's test method for consistency. Hence, this validated model was further employed for screening of natural hit compounds from InterBioScreen Natural product database, consisting of more than 60,000 natural compounds and derivatives. The screened hit compounds were subsequently filtered by Lipinski's rule of 5, ADME and toxicity parameters and molecular docking studies to remove the false positive rates. Finally, molecular docking analysis led to identification of the (3a'S,6a'R)-3'-(3,4-dihydroxybenzyl)-5'-(3,4-dimethoxyphenethyl)-5-ethyl-3',3a'-dihydro-2'H-spiro[indoline-3,1'-pyrrolo[3,4-c]pyrrole]-2,4',6'(5'H,6a'H)-trione (Compound ID: STOCK1N-65837) as potent hTLR7 modulator due to its better docking score and molecular interactions compared to other compounds. The result of virtual screening was further validated using molecular dynamics (MD) simulation analysis. Thus, a 30 ns MD simulation analysis revealed high stability and effective binding of STOCK1N-65837 within the binding site of hTLR7. Therefore, the present study provides confidence for the utility of the selected chemical feature based pharmacophore model to design novel TLR7 modulators with desired biological activity.
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Affiliation(s)
- Chhedi Lal Gupta
- Institute for Development of Advanced computing, ONGC Centre for Advanced studies, University of Lucknow , Lucknow , UP , India.,Molecular Immunology Laboratory, Department of Biosciences, Integral University , Lucknow , UP , India
| | - Mohd Babu Khan
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University , Puducherry , India
| | - Dinakara Rao Ampasala
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University , Puducherry , India
| | - Salman Akhtar
- Department of Bioengineering, Integral University , Lucknow , UP , India
| | - Upendra Nath Dwivedi
- Institute for Development of Advanced computing, ONGC Centre for Advanced studies, University of Lucknow , Lucknow , UP , India.,Department of Biochemistry, Centre of Excellence in Bioinformatics, Bioinformatics Infrastructure Facility, University of Lucknow , Lucknow , UP , India
| | - Preeti Bajpai
- Molecular Immunology Laboratory, Department of Biosciences, Integral University , Lucknow , UP , India
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13
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Guan ZR, Liu ZM, Ding MW. New efficient synthesis of 1H-imidazo-[4,5-c]quinolines by a sequential Van Leusen/Staudinger/aza-Wittig/carbodiimide-mediated cyclization. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.10.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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14
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Yoo E, Salyer ACD, Brush MJH, Li Y, Trautman KL, Shukla NM, De Beuckelaer A, Lienenklaus S, Deswarte K, Lambrecht BN, De Geest BG, David SA. Hyaluronic Acid Conjugates of TLR7/8 Agonists for Targeted Delivery to Secondary Lymphoid Tissue. Bioconjug Chem 2018; 29:2741-2754. [DOI: 10.1021/acs.bioconjchem.8b00386] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Euna Yoo
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Alex C. D. Salyer
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Michael J. H. Brush
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Yupeng Li
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kathryn L. Trautman
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Nikunj M. Shukla
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ans De Beuckelaer
- Department of Pharmaceutics and Center for Inflammation Research, Ghent University, 9000 Ghent, Belgium
| | - Stefan Lienenklaus
- Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany
| | - Kim Deswarte
- Department of Pharmaceutics and Center for Inflammation Research, Ghent University, 9000 Ghent, Belgium
| | - Bart N. Lambrecht
- Department of Pharmaceutics and Center for Inflammation Research, Ghent University, 9000 Ghent, Belgium
| | - Bruno G. De Geest
- Department of Pharmaceutics and Center for Inflammation Research, Ghent University, 9000 Ghent, Belgium
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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Salyer ACD, David SA. Transcriptomal signatures of vaccine adjuvants and accessory immunostimulation of sentinel cells by toll-like receptor 2/6 agonists. Hum Vaccin Immunother 2018; 14:1686-1696. [PMID: 29852079 PMCID: PMC6067887 DOI: 10.1080/21645515.2018.1480284] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 05/09/2018] [Accepted: 05/21/2018] [Indexed: 12/20/2022] Open
Abstract
An important component of vaccine development is the identification of safe and effective adjuvants. We sought to identify transcriptomal signatures of innate immune stimulating molecules using next-generation RNA sequencing with the goal of being able to utilize such signatures in identifying novel immunostimulatory compounds with adjuvant activity. The CC family of chemokines, particularly CC chemokines 1, 2, 3, 4, 7, 8, 17, 18, 20, and 23, were broadly upregulated by most Toll-like receptor (TLR) and nucleotide-binding domain and leucine-rich repeat-containing receptors (NLR) stimuli. Extracellular receptors such as TLR2, TLR4 and TLR5 induced the transcription of CXC chemokines including CXCL5, CXCL6 and CXCL8, whereas intracellular receptors such as TLR7 and TLR8 upregulated CXC chemokines 11 and 12. Both TLR1/2 and TLR2/6 agonists induced strong chemokine production in human peripheral blood mononuclear cells. Human skeletal muscle cells and fibroblasts respond with chemokine production only to TLR2/6 agonists, but not TLR1/2 agonists, consistent with strong expression of TLR2 and TLR6, but not of TLR1, in fibroblasts. TLR2/6 stimulated fibroblasts demonstrated functional chemotactic responses to human T cell and natural killer cells subsets. The activation of non-hematopoietic, adventitial cells such as fibroblasts and myocytes may contribute.
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Affiliation(s)
- Alex C. D. Salyer
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
- Center for Immunology, University of Minnesota, Minneapolis, MN, USA
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16
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Bazin HG, Bess LS, Livesay MT. Synthesis and Applications of Imidazoquinolines: A Review. ORG PREP PROCED INT 2018. [DOI: 10.1080/00304948.2018.1433427] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Hélène G. Bazin
- Biomedical & Pharmaceutical Science, University of Montana, 32 Campus Drive #1552, Missoula, MT 59812, USA
| | - Laura S. Bess
- Biomedical & Pharmaceutical Science, University of Montana, 32 Campus Drive #1552, Missoula, MT 59812, USA
| | - Mark T. Livesay
- Biomedical & Pharmaceutical Science, University of Montana, 32 Campus Drive #1552, Missoula, MT 59812, USA
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17
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Ignacio BJ, Albin TJ, Esser-Kahn AP, Verdoes M. Toll-like Receptor Agonist Conjugation: A Chemical Perspective. Bioconjug Chem 2018; 29:587-603. [PMID: 29378134 PMCID: PMC10642707 DOI: 10.1021/acs.bioconjchem.7b00808] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Toll-like receptors (TLRs) are vital elements of the mammalian immune system that function by recognizing pathogen-associated molecular patterns (PAMPs), bridging innate and adaptive immunity. They have become a prominent therapeutic target for the treatment of infectious diseases, cancer, and allergies, with many TLR agonists currently in clinical trials or approved as immunostimulants. Numerous studies have shown that conjugation of TLR agonists to other molecules can beneficially influence their potency, toxicity, pharmacokinetics, or function. The functional properties of TLR agonist conjugates, however, are highly dependent on the ligation strategy employed. Here, we review the chemical structural requirements for effective functional TLR agonist conjugation. In addition, we provide similar analysis for those that have yet to be conjugated. Moreover, we discuss applications of covalent TLR agonist conjugation and their implications for clinical use.
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Affiliation(s)
- Bob J. Ignacio
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Tyler J. Albin
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Aaron P. Esser-Kahn
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Martijn Verdoes
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
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18
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Recent progress of fully synthetic carbohydrate-based vaccine using TLR agonist as build-in adjuvant. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2017.09.047] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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19
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Xu Z, Moyle PM. Bioconjugation Approaches to Producing Subunit Vaccines Composed of Protein or Peptide Antigens and Covalently Attached Toll-Like Receptor Ligands. Bioconjug Chem 2017; 29:572-586. [PMID: 28891637 DOI: 10.1021/acs.bioconjchem.7b00478] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Traditional vaccines derived from attenuated or inactivated pathogens are effective at inducing antibody-based protective immune responses but tend to be highly reactogenic, causing notable adverse effects. Vaccines with superior safety profiles can be produced by subunit approaches, utilizing molecularly defined antigens (e.g., proteins and polysaccharides). These antigens, however, often elicit poor immunological responses, necessitating the use of adjuvants. Immunostimulatory adjuvants have the capacity to activate antigen presenting cells directly through specific receptors (e.g., Toll-like receptors (TLRs)), resulting in enhanced presentation of antigens as well as the secretion of proinflammatory chemokines and cytokines. Consequently, innate immune responses are amplified and adaptive immunity is generated. Recently, site-specific conjugation of such immunostimulatory adjuvants (e.g., TLR ligands) onto defined antigens has shown superior efficacy over unconjugated mixtures, suggesting that the development of chemically characterized immunostimulatory adjuvants and optimized approaches for their conjugation with antigens may provide a better opportunity for the development of potent, novel vaccines. This review briefly summarizes various TLR agonists utilized as immunostimulatory adjuvants and focuses on the development of techniques (e.g., recombinant, synthetic, and semisynthetic) for generating adjuvant-antigen fusion vaccines incorporating peptide or protein antigens.
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Affiliation(s)
- Zhenghui Xu
- School of Pharmacy , The University of Queensland , Woolloongabba 4102 , Queensland , Australia
| | - Peter Michael Moyle
- School of Pharmacy , The University of Queensland , Woolloongabba 4102 , Queensland , Australia
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20
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Beesu M, Salyer ACD, Brush MJH, Trautman KL, Hill JK, David SA. Identification of High-Potency Human TLR8 and Dual TLR7/TLR8 Agonists in Pyrimidine-2,4-diamines. J Med Chem 2017; 60:2084-2098. [PMID: 28146629 DOI: 10.1021/acs.jmedchem.6b01860] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The induction of toll-like receptor 7 (TLR7)-dependent type I interferons (IFN-α/β) from plasmacytoid dendritic cells as well as the production of TLR8-dependent type II interferon (IFN-γ), TNF-α, and IL-12 in myeloid dendritic cells are of importance in generating T helper-1 biased adaptive immune responses. In an effort to identify novel dual TLR7/TLR8-active compounds, we undertook structure-activity relationship studies in pyrimidine 2,4-diamines, focusing on substituents at C5. Several analogues substituted with aminopropyl appendages at C5 displayed dominant TLR8-agonistic activity. N4-Butyl-6-methyl-5-(3-morpholinopropyl)pyrimidine-2,4-diamine was found to be a very potent dual TLR7/TLR8 agonist. Employing novel cytokine reporter cell assays, we verified that potency at TLR7 correlates with IFN-α/β production in human blood, whereas IFN-γ and TNF-α induction is largely TLR8-dependent. Dual TLR7/TLR8 agonists markedly upregulate CD80 expression in multiple dendritic cell subsets, providing insight into the immunological basis for the superior adjuvantic properties of such innate immune stimuli.
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Affiliation(s)
- Mallesh Beesu
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Alex C D Salyer
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Michael J H Brush
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Kathryn L Trautman
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Justin K Hill
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
| | - Sunil A David
- Department of Medicinal Chemistry, University of Minnesota , Sixth Street SE, Minneapolis, Minnesota 55455, United States
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21
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Abstract
Human toll-like receptor (hTLR)-8 is expressed in myeloid dendritic cells, monocytes, and monocyte-derived dendritic cells. Engagement by TLR8 agonists evokes a distinct cytokine profile which favors the development of type 1 helper T cells. Focused exploration of structure-activity relationships in the imidazoquinolines has led to the identification of several novel human TLR8-specific agonists. The synthetic procedures for best-in-class analogues encompassing four chemotypes are described.
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Affiliation(s)
- Mallesh Beesu
- Department of Medicinal Chemistry, University of Minnesota, 2-132, Cancer & Cardiovascular Research Building, 2231 6th Street SE, Minneapolis, MN, 55455, USA
| | - Hari Prasad Kokatla
- Department of Medicinal Chemistry, University of Minnesota, 2-132, Cancer & Cardiovascular Research Building, 2231 6th Street SE, Minneapolis, MN, 55455, USA
| | - Sunil A David
- Department of Medicinal Chemistry, University of Minnesota, 2-132, Cancer & Cardiovascular Research Building, 2231 6th Street SE, Minneapolis, MN, 55455, USA.
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22
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Francica JR, Lynn GM, Laga R, Joyce MG, Ruckwardt TJ, Morabito KM, Chen M, Chaudhuri R, Zhang B, Sastry M, Druz A, Ko K, Choe M, Pechar M, Georgiev IS, Kueltzo LA, Seymour LW, Mascola JR, Kwong PD, Graham BS, Seder RA. Thermoresponsive Polymer Nanoparticles Co-deliver RSV F Trimers with a TLR-7/8 Adjuvant. Bioconjug Chem 2016; 27:2372-2385. [PMID: 27583777 DOI: 10.1021/acs.bioconjchem.6b00370] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Structure-based vaccine design has been used to develop immunogens that display conserved neutralization sites on pathogens such as HIV-1, respiratory syncytial virus (RSV), and influenza. Improving the immunogenicity of these designed immunogens with adjuvants will require formulations that do not alter protein antigenicity. Here, we show that nanoparticle-forming thermoresponsive polymers (TRP) allow for co-delivery of RSV fusion (F) protein trimers with Toll-like receptor 7 and 8 agonists (TLR-7/8a) to enhance protective immunity. Although primary amine conjugation of TLR-7/8a to F trimers severely disrupted the recognition of critical neutralizing epitopes, F trimers site-selectively coupled to TRP nanoparticles retained appropriate antigenicity and elicited high titers of prefusion-specific, TH1 isotype anti-RSV F antibodies following vaccination. Moreover, coupling F trimers to TRP delivering TLR-7/8a resulted in ∼3-fold higher binding and neutralizing antibody titers than soluble F trimers admixed with TLR-7/8a and conferred protection from intranasal RSV challenge. Overall, these data show that TRP nanoparticles may provide a broadly applicable platform for eliciting neutralizing antibodies to structure-dependent epitopes on RSV, influenza, HIV-1, or other pathogens.
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Affiliation(s)
- Joseph R Francica
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Geoffrey M Lynn
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Richard Laga
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , 162 06 Prague, Czech Republic
| | - M Gordon Joyce
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Tracy J Ruckwardt
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Kaitlyn M Morabito
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Rajoshi Chaudhuri
- Vaccine Production Program, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Gaithersburg, Maryland 20878, United States
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Mallika Sastry
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Aliaksandr Druz
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Kiyoon Ko
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Misook Choe
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Michal Pechar
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , 162 06 Prague, Czech Republic
| | - Ivelin S Georgiev
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Lisa A Kueltzo
- Vaccine Production Program, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Gaithersburg, Maryland 20878, United States
| | | | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Robert A Seder
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
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23
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Sharghi H, Aberi M, Aboonajmi J. One-pot synthesis of 2,4-disubstituted quinolines via three-component reaction of amines, aldehydes and alkynes using Al2O3 nanoparticles/methanesulfonic acid (nano-AMA) as a new catalyst. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2016. [DOI: 10.1007/s13738-016-0941-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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24
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Gao D, Zeng J, Wang X, Liu Y, Li W, Hu Y, Gao N, Diao Y, Wang Z, Jiang W, Chen J, Jin G. Conjugation of weak ligands with weak antigens to activate TLR-7: A step toward better vaccine adjuvants. Eur J Med Chem 2016; 120:111-20. [DOI: 10.1016/j.ejmech.2016.04.070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 12/20/2022]
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25
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Kim WG, Choi B, Yang HJ, Han JA, Jung H, Cho H, Kang S, Hong SY. Covalent Conjugation of Small-Molecule Adjuvants to Nanoparticles Induces Robust Cytotoxic T Cell Responses via DC Activation. Bioconjug Chem 2016; 27:2007-13. [PMID: 27504746 DOI: 10.1021/acs.bioconjchem.6b00277] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Specific recognitions of pathogen associated molecular patterns by Toll-like receptors (TLRs) initiate dendritic cell (DC) activation, which is critical for coordinating innate and adaptive immune responses. Imidazoquinolines as small-molecule TLR7 agonists often suffer from prompt dissemination and short half-life in the bloodstream, preventing their localization to the corresponding receptors and effective DC activation. We postulated that covalent incorporation of imidazoquinoline moieties onto the surface of biocompatible nanoparticles (∼30 nm size) would enhance their chemical stability, cellular uptake efficiency, and adjuvanticity. The fully synthetic adjuvant-nanocomplexes led to successful DC activation at lower nanomolar doses compared with free small-molecule agonists. Once a model antigen such as ovalbumin was used for immunization, we found that the nanocomplexes promoted an unusually strong cytotoxic T lymphocyte response, revealing their unique immunostimulatory capacity benefiting from multivalency and efficient transport to endosomal TLR7.
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Affiliation(s)
- Woo Gyum Kim
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Bongseo Choi
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Hyun-Ji Yang
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Jae-A Han
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Hoesu Jung
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - HyungJoon Cho
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Sebyung Kang
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
| | - Sung You Hong
- School of Energy and Chemical Engineering and ‡School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST) , UNIST-gil 50, Ulsan 689-798, Republic of Korea
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26
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Beesu M, Salyer ACD, Trautman KL, Hill JK, David SA. Human Toll-like Receptor (TLR) 8-Specific Agonistic Activity in Substituted Pyrimidine-2,4-diamines. J Med Chem 2016; 59:8082-93. [DOI: 10.1021/acs.jmedchem.6b00872] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Mallesh Beesu
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Alex C. D. Salyer
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kathryn L. Trautman
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Justin K. Hill
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sunil A. David
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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27
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Akinbobuyi B, Wang L, Upchurch KC, Byrd MR, Chang CA, Quintana JM, Petersen RE, Seifert ZJ, Boquin JR, Oh S, Kane RR. Synthesis and immunostimulatory activity of substituted TLR7 agonists. Bioorg Med Chem Lett 2016; 26:4246-9. [PMID: 27476423 DOI: 10.1016/j.bmcl.2016.07.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 07/20/2016] [Accepted: 07/21/2016] [Indexed: 11/18/2022]
Abstract
Fifteen new substituted adenines were synthesized as potential TLR7 agonists. These compounds, along with 9 previously reported compounds, were analyzed for TLR7 activity and for the selective stimulation of B cell proliferation. Several functionalized derivatives exhibit significant activity, suggesting their potential for use as vaccine adjuvants.
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Affiliation(s)
- Babatope Akinbobuyi
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Lei Wang
- Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Katherine C Upchurch
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Matthew R Byrd
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Charles A Chang
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - Jeremy M Quintana
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Rachel E Petersen
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Zacharie J Seifert
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - José R Boquin
- Department of Chemistry, Augustana College, 639 38th Street, Rock Island, IL 61201, USA
| | - SangKon Oh
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Robert R Kane
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA; Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA.
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28
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Beesu M, Caruso G, Salyer ACD, Shukla NM, Khetani KK, Smith LJ, Fox LM, Tanji H, Ohto U, Shimizu T, David SA. Identification of a Human Toll-Like Receptor (TLR) 8-Specific Agonist and a Functional Pan-TLR Inhibitor in 2-Aminoimidazoles. J Med Chem 2016; 59:3311-30. [PMID: 26966993 DOI: 10.1021/acs.jmedchem.6b00023] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Activation of human toll-like receptor-8 (TLR8), expressed in myeloid dendritic cells, monocytes, and monocyte-derived dendritic cells, evokes a distinct cytokine profile which favors the development of Type 1 helper T cells. Part-structures of the 2-aminobenzimidazole scaffold were examined with a view to identifying structural requisites corresponding to the smallest possible fragment of the benzimidazole core that would allow for retention of TLR8-agonistic activity. TLR8-specific agonistic activity was retained in 1-pentyl-4-phenyl-1H-imidazol-2-amine. The crystal structure of this compound bound to the TLR8 ectodomain displayed binding interactions that are common to other TLR8 agonists. This compound showed markedly attenuated proinflammatory properties in ex vivo human blood models. SAR studies revealed that 4-(2-(benzyloxy)phenyl)-1-pentyl-1H-imidazol-2-amine inhibited TLR signaling in a variety of TLR reporter cell lines, as well as in pharmacologically relevant human blood model systems. A kinase screen of this compound showed relative specificity for calmodulin kinases.
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Affiliation(s)
- Mallesh Beesu
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States.,Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Giuseppe Caruso
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Alex C D Salyer
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States.,Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Nijunj M Shukla
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States.,Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Karishma K Khetani
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Luke J Smith
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Lauren M Fox
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Hiromi Tanji
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo, Japan
| | - Umeharu Ohto
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo, Japan
| | - Toshiyuki Shimizu
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo, Japan
| | - Sunil A David
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States.,Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
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29
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Salyer ACD, Caruso G, Khetani KK, Fox LM, Malladi SS, David SA. Identification of Adjuvantic Activity of Amphotericin B in a Novel, Multiplexed, Poly-TLR/NLR High-Throughput Screen. PLoS One 2016; 11:e0149848. [PMID: 26919709 PMCID: PMC4769227 DOI: 10.1371/journal.pone.0149848] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/05/2016] [Indexed: 01/26/2023] Open
Abstract
Small-molecule agonists have been identified for TLR7, TLR8, TLR4 and TLR2 thus far, and chemotypes other than those of canonical ligands are yet to be explored for a number of innate immune receptors. The discovery of novel immunostimulatory molecules would enhance the repertoire of tools available for interrogating innate immune effector mechanisms, and provide additional venues for vaccine adjuvant development. A multiplexed, reporter gene-based high-throughput assay capable of detecting agonists of TLR2, TLR3, TLR4, TLR5, TLR7, TLR8, TLR9, NOD1 and NOD2 was utilized in screening 123,943 compounds, in which amphotericin B (AmpB) and nystatin were identified as prominent hits. The polyene antifungal agents act as TLR2- and TLR4-agonists. The TLR4-stimulatory activity of AmpB was similar to that of monophosphoryl lipid A, suggestive of TRIF-biased signaling. The adjuvantic activity of AmpB, at a dose of 100 micrograms, was comparable to several other candidate adjuvants in rabbit models of immunization. These results point to its potential applicability as a safe and effective adjuvant for human vaccines.
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Affiliation(s)
- Alex C. D. Salyer
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Giuseppe Caruso
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Karishma K. Khetani
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Lauren M. Fox
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Subbalakshmi S. Malladi
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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30
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Fujita Y, Hirai K, Nishida K, Taguchi H. 6-(4-Amino-2-butyl-imidazoquinolyl)-norleucine: Toll-like receptor 7 and 8 agonist amino acid for self-adjuvanting peptide vaccine. Amino Acids 2016; 48:1319-29. [PMID: 26874701 DOI: 10.1007/s00726-016-2190-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 01/28/2016] [Indexed: 10/22/2022]
Abstract
Generally, small peptides by themselves are weak to induce antibody responses. Toll-like receptor (TLR) ligands are attractive candidates of vaccine adjuvants to improve their antigenicity. The covalent conjugation of TLR ligands with antigens to produce self-adjuvanting peptide vaccine is a promising approach. Based on the structure of TLR7/8 ligands, a series of synthetic amino acids 6-imidazoquinolyl-norleucines were synthesized, wherein an imidazoquinoline structure as the TLR7/8 agonistic pharmacophores was constructed on the ε-NH2 group of Lys. Of them, 6-(4-amino-2-butyl-imidazoquinolyl)-norleucine showed the most potent TLR7 and TLR8 agonistic activities with EC50 values of 8.55 and 106 μM, respectively. Subsequently, mice were immunized with the influenza A virus M2e antigen mixed with or covalently conjugated to the TLR7/8 agonist amino acid, which led to induction of M2e specific antibody productions in the absence of other adjuvant. We successfully developed a novel efficient tool for self-adjuvanting peptide vaccines targeting TLR7/8.
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Affiliation(s)
- Yoshio Fujita
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3, Minami-Tamagaki, Suzuka, Mie, 513-8670, Japan.
| | - Kazuyuki Hirai
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3, Minami-Tamagaki, Suzuka, Mie, 513-8670, Japan
| | - Keigo Nishida
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3, Minami-Tamagaki, Suzuka, Mie, 513-8670, Japan
| | - Hiroaki Taguchi
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3, Minami-Tamagaki, Suzuka, Mie, 513-8670, Japan
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31
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Lynn GM, Laga R, Darrah PA, Ishizuka AS, Balaci AJ, Dulcey AE, Pechar M, Pola R, Gerner MY, Yamamoto A, Buechler CR, Quinn KM, Smelkinson MG, Vanek O, Cawood R, Hills T, Vasalatiy O, Kastenmuller K, Francica JR, Stutts L, Tom JK, Ryu KA, Esser-Kahn AP, Etrych T, Fisher KD, Seymour LW, Seder RA. In vivo characterization of the physicochemical properties of polymer-linked TLR agonists that enhance vaccine immunogenicity. Nat Biotechnol 2015; 33:1201-10. [PMID: 26501954 PMCID: PMC5842712 DOI: 10.1038/nbt.3371] [Citation(s) in RCA: 315] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 09/14/2015] [Indexed: 02/06/2023]
Abstract
The efficacy of vaccine adjuvants such as Toll-like receptor agonists (TLRa) can be improved through formulation and delivery approaches. Here, we attached small molecule TLR-7/8a to polymer scaffolds (polymer-TLR-7/8a) and evaluated how different physicochemical properties of the TLR-7/8a and polymer carrier influenced the location, magnitude and duration of innate immune activation in vivo. Particle formation by polymer-TLR-7/8a was the most important factor for restricting adjuvant distribution and prolonging activity in draining lymph nodes. The improved pharmacokinetic profile by particulate polymer-TLR-7/8a was also associated with reduced morbidity and enhanced vaccine immunogenicity for inducing antibodies and T cell immunity. We extended these findings to the development of a modular approach in which protein antigens are site-specifically linked to temperature-responsive polymer-TLR-7/8a adjuvants that self-assemble into immunogenic particles at physiologic temperatures in vivo. Our findings provide a chemical and structural basis for optimizing adjuvant design to elicit broad-based antibody and T cell responses with protein antigens.
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Affiliation(s)
- Geoffrey M. Lynn
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Richard Laga
- Department of Oncology, University of Oxford, Oxford, United Kingdom
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Patricia A. Darrah
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Andrew S. Ishizuka
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alexandra J. Balaci
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Andrés E. Dulcey
- Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA
| | - Michal Pechar
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Robert Pola
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Michael Y. Gerner
- Lymphocyte Biology Section, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ayako Yamamoto
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Connor R. Buechler
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kylie M. Quinn
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Margery G. Smelkinson
- Biological Imaging Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ondrej Vanek
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Ryan Cawood
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Thomas Hills
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Olga Vasalatiy
- Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA
| | - Kathrin Kastenmuller
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Joseph R. Francica
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Lalisa Stutts
- Department of Chemistry, University of California Irvine, Irvine, California, USA
| | - Janine K. Tom
- Department of Chemistry, University of California Irvine, Irvine, California, USA
| | - Keun Ah Ryu
- Department of Chemistry, University of California Irvine, Irvine, California, USA
| | - Aaron P. Esser-Kahn
- Department of Chemistry, University of California Irvine, Irvine, California, USA
| | - Tomas Etrych
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Kerry D. Fisher
- Department of Oncology, University of Oxford, Oxford, United Kingdom
| | | | - Robert A. Seder
- Vaccine research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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32
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Beesu M, Caruso G, Salyer ACD, Khetani KK, Sil D, Weerasinghe M, Tanji H, Ohto U, Shimizu T, David SA. Structure-Based Design of Human TLR8-Specific Agonists with Augmented Potency and Adjuvanticity. J Med Chem 2015; 58:7833-49. [PMID: 26351878 PMCID: PMC4601487 DOI: 10.1021/acs.jmedchem.5b01087] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
![]()
Human
Toll-like receptor 8 (hTLR8) is expressed in myeloid dendritic cells,
monocytes, and monocyte-derived dendritic cells. Engagement by TLR8
agonists evokes a distinct cytokine profile which favors the development
of type 1 helper T cells. Crystal structures of the ectodomain of
hTLR8 cocrystallized with two regioisomers of a dual TLR7/8-agonistic
N1-substituted imidazoquinolines showed subtle differences in their
interactions in the binding site of hTLR8. We hypothesized that the
potency of a previously reported best-in-class pure TLR8 agonist,
3-pentylquinoline-2-amine, could be further enhanced by “designing
in” functional groups that would mimic key intermolecular interactions
that we had observed in the crystal structures. We performed a focused
exploration of decorating the quinoline core with alkylamino groups
at all possible positions. These studies have led to the identification
of a novel TLR8 agonist that was ∼20-fold more potent than
the parent compound and displays prominent adjuvantic activity in
a rabbit model of immunization.
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Affiliation(s)
- Mallesh Beesu
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Giuseppe Caruso
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Alex C D Salyer
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Karishma K Khetani
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Diptesh Sil
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Mihiri Weerasinghe
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
| | - Hiromi Tanji
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo 113-0033, Japan
| | - Umeharu Ohto
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo 113-0033, Japan
| | - Toshiyuki Shimizu
- Graduate School of Pharmaceutical Sciences, University of Tokyo , Tokyo 113-0033, Japan
| | - Sunil A David
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
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33
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Abstract
Antigen- and adjuvant-based bioconjugates that can stimulate the immune system play an important role in vaccine applications. Bioconjugates have demonstrated unique physicochemical and biological properties, enabling vaccines to be delivered to key immune cells, to target specific intracellular pathways, or to mimic immunogenic properties of natural pathogens. In this Review we highlight recent advances in such molecular immunomodulators, with an emphasis on the structure-function relationships that provide the foundation for rational design of safe and effective vaccines and immunotherapies.
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Affiliation(s)
- Haipeng Liu
- †Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan 48202, United States
- ‡Department of Oncology, Wayne State University, Detroit, Michigan 48201, United States
- §Tumor Biology and Microenvironment Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, United States
| | - Darrell J Irvine
- ▼Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, United States
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34
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Gao D, Diao Y, Li W, Gao N, Liu Y, Wang Z, Jiang W, Jin G. Toll-like receptor 7 inactive ligands enhanced cytokine induction by conjugation to weak antigens. ChemMedChem 2015; 10:977-80. [PMID: 25882779 DOI: 10.1002/cmdc.201500088] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 03/25/2015] [Indexed: 11/09/2022]
Abstract
Toll-like receptors (TLRs) 7/8 are key targets in the design and development of small-molecule drugs serving as anticancer/antiviral agents and vaccine adjuvants. Clinical trials of imiquimod were discontinued owing to its serious adverse side effects. Herein we report the synthesis and biological evaluation of a series of 8-hydroxy-2-(2-methoxyethoxy)adenine derivatives that cannot induce cytokine production and that lack activity toward TLR 7/8. Their ability to triggering remarkable levels of cytokine production were revealed upon their conjugation with antigens that have weak immunogenicity. This discovery demonstrated that TLR 7 can be activated by coupling an antigen to the terminal carboxyl group at N9 of the inactive ligand adenine analogues. These inactive analogues may be well suited as new adjuvants with superior activity after conjugation, effectively decreasing the side effects caused by conventional adjuvants.
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Affiliation(s)
- Dong Gao
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China). .,Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education, Shenzhen University, Shenzhen 518060 (P. R. China).
| | - Yuwen Diao
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Wang Li
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Ningning Gao
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Yu Liu
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China).,Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Zhulin Wang
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Wenqi Jiang
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China)
| | - Guangyi Jin
- Cancer Research Center, Shenzhen University, Shenzhen 518060 (P. R. China).
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35
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Gao D, Liu Y, Diao Y, Gao N, Wang Z, Jiang W, Jin G. Synthesis and Evaluation of Conjugates of Novel TLR7 Inert Ligands as Self-Adjuvanting Immunopotentiators. ACS Med Chem Lett 2015; 6:249-53. [PMID: 25815141 DOI: 10.1021/ml5003647] [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: 09/07/2014] [Accepted: 01/30/2015] [Indexed: 01/21/2023] Open
Abstract
During the design and synthesis of a series of 8-hydroxy-2-(2-methoxyethoxy)-adenine derivatives bearing various substituted -RCOOH groups at the 9-position, we identified a TLR7-inert ligand, which does not activate TLR7 signaling pathway. Of interest, the coupling of weakly immunogenic antigens via the -RCOOH group was able to significantly enhance the immunogenicity of the antigens. Herein, an inert ligand, 9-(3-carboxypropyl)-8-hydroxy-2-(2-methoxyethoxy)-adenine (5, GD2), was synthesized and conjugated to 5 different weakly immunogenic antigens (BSA, OVA, MSA, MG7, and thymosin). Compared with the GD2 and the potent agonist UC-1 V150, all conjugates demonstrated potent immunogenicity in vitro and in vivo. All conjugates induced prolonged increases, while UC-1 V150 showed a rapid decline in the levels of proinflammatory cytokines following initial increases. These data indicate that the immunostimulatory activity of TLR7-inert ligands could be amplified and prolonged by conjugation to antigens, thus broadening the potential therapeutic application of these agents.
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Affiliation(s)
- Dong Gao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
- Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Yu Liu
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
- Key Laboratory of Optoelectronic Devices
and Systems of Ministry of Education, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yuwen Diao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Ningning Gao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Zhulin Wang
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Wenqi Jiang
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
- Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Guangyi Jin
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
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36
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Abstract
Vaccination has a proven record as one of the most effective medical approaches to prevent the spread of infectious diseases. Traditional vaccine approaches involve the administration of whole killed or weakened microorganisms to stimulate protective immune responses. Such approaches deliver many microbial components, some of which contribute to protective immunity, and assist in guiding the type of immune response that is elicited. Despite their impeccable record, these approaches have failed to yield vaccines for many important infectious organisms. This has prompted a move towards more defined vaccines ('subunit vaccines'), where individual protective components are administered. This unit provides an overview of the components that are used for the development of modern vaccines including: an introduction to different vaccine types (whole organism, protein/peptide, polysaccharide, conjugate, and DNA vaccines); techniques for identifying subunit antigens; vaccine delivery systems; and immunostimulatory agents ('adjuvants'), which are fundamental for the development of effective subunit vaccines.
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37
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Akinbobuyi B, Byrd MR, Chang CA, Nguyen M, Seifert ZJ, Flamar AL, Zurawski G, Upchurch KC, Oh S, Dempsey SH, Enke TJ, Le J, Winstead HJ, Boquín JR, Kane RR. Facile syntheses of functionalized toll-like receptor 7 agonists. Tetrahedron Lett 2015; 56:458-460. [PMID: 25601818 DOI: 10.1016/j.tetlet.2014.11.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Protein conjugates of toll-like receptor 7 agonists have been shown to elicit powerful immune responses. In order to facilitate our studies in this area our group has developed efficient syntheses for a number of functionalized derivatives that retain immune stimulatory activity.
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Affiliation(s)
- Babatope Akinbobuyi
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Matthew R Byrd
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Charles A Chang
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - Mysa Nguyen
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Zacharie J Seifert
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Anne-Laure Flamar
- Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Gerard Zurawski
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Katherine C Upchurch
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - SangKon Oh
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Stephen H Dempsey
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Thomas J Enke
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - John Le
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Hunter J Winstead
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - José R Boquín
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Robert R Kane
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA ; Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
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38
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Gao D, Liu Y, Li W, Zhong F, Zhang X, Diao Y, Gao N, Wang X, Jiang W, Jin G. Synthesis and immunoregulatory activities of conjugates of a Toll-like receptor 7 inert ligand. Bioorg Med Chem Lett 2014; 24:5792-5795. [PMID: 25453821 DOI: 10.1016/j.bmcl.2014.10.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 08/26/2014] [Accepted: 10/09/2014] [Indexed: 01/12/2023]
Abstract
In the synthesis and modification of the analogs of an adenine type of Toll-like receptor (TLR) 7 agonists, we found a special compound, 9-propionyloxy-8-hydroxy-2-(2-methoxyethoxy)-adenine (6). It is a synthesized TLR7 inert ligand, which does not respond to TLR7 itself. However, it can be coupled with protein or peptide antigens via propionyloxy functional group to promote their immunogenicity significantly. The compound was covalently coupled to protein and peptide to get the conjugates. The inductivity of cytokine production by the conjugates was 872.4-fold compared with the unconjugated antigens in vitro by mouse splenocyte. These data show that the immunostimulatory activity of inert TLR7 ligand can be endowed, and the activity of antigens can be amplified by conjugation with various proteins and peptides, thus broadening the potential therapeutic application and reducing the risk of TLR7 agonists' side effects.
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Affiliation(s)
- Dong Gao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China; Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Yu Liu
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Wang Li
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Fangshu Zhong
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Xiaoli Zhang
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Yuwen Diao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Ningning Gao
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Xiaodong Wang
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China
| | - Wenqi Jiang
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China; Sun Yat-sen University Cancer Center, Guangzhou 510060, China.
| | - Guangyi Jin
- Shenzhen University Cancer Research Center, Institute of Otorhinolaryngology, Shenzhen 518060, China.
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39
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Beesu M, Malladi SS, Fox LM, Jones CD, Dixit A, David SA. Human Toll-like receptor 8-selective agonistic activities in 1-alkyl-1H-benzimidazol-2-amines. J Med Chem 2014; 57:7325-41. [PMID: 25102141 PMCID: PMC4161153 DOI: 10.1021/jm500701q] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
![]()
Toll-like
receptor (TLR)-8 agonists strongly induce the production
of T helper 1-polarizing cytokines and may therefore serve as promising
candidate vaccine adjuvants, especially for the very young and the
elderly. Earlier structure-based ligand design led to the identification
of 3-pentyl-quinoline-2-amine as a novel, human TLR8-specific agonist.
Comprehensive structure–activity relationships in ring-contracted
1-alkyl-1H-benzimidazol-2-amines were undertaken,
and the best-in-class compound, 4-methyl-1-pentyl-1H-benzo[d]imidazol-2-amine, was found to be a pure
TLR8 agonist, evoking strong proinflammatory cytokine and Type II
interferon responses in human PBMCs, with no attendant CD69 upregulation
in natural lymphocytic subsets. The 1-alkyl-1H-benzimidazol-2-amines
represent a novel, alternate chemotype with pure TLR8-agonistic activities
and will likely prove useful not only in understanding TLR8 signaling
but also perhaps as a candidate vaccine adjuvant.
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Affiliation(s)
- Mallesh Beesu
- Department of Medicinal Chemistry, University of Kansas , Lawrence, Kansas 66047, United States
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Bergmann-Leitner ES, Leitner WW. Adjuvants in the Driver's Seat: How Magnitude, Type, Fine Specificity and Longevity of Immune Responses Are Driven by Distinct Classes of Immune Potentiators. Vaccines (Basel) 2014; 2:252-96. [PMID: 26344620 PMCID: PMC4494256 DOI: 10.3390/vaccines2020252] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 03/20/2014] [Accepted: 03/28/2014] [Indexed: 12/16/2022] Open
Abstract
The mechanism by which vaccine adjuvants enhance immune responses has historically been considered to be the creation of an antigen depot. From here, the antigen is slowly released and provided to immune cells over an extended period of time. This "depot" was formed by associating the antigen with substances able to persist at the injection site, such as aluminum salts or emulsions. The identification of Pathogen-Associated Molecular Patterns (PAMPs) has greatly advanced our understanding of how adjuvants work beyond the simple concept of extended antigen release and has accelerated the development of novel adjuvants. This review focuses on the mode of action of different adjuvant classes in regards to the stimulation of specific immune cell subsets, the biasing of immune responses towards cellular or humoral immune response, the ability to mediate epitope spreading and the induction of persistent immunological memory. A better understanding of how particular adjuvants mediate their biological effects will eventually allow them to be selected for specific vaccines in a targeted and rational manner.
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Affiliation(s)
- Elke S Bergmann-Leitner
- US Military Malaria Research Program, Malaria Vaccine Branch, 503 Robert Grant Ave, 3W65, Silver Spring, MD 20910, USA.
| | - Wolfgang W Leitner
- Division on Allergy, Immunology and Transplantation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 6610 Rockledge Drive, Bethesda, MD 20892, USA.
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41
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Vasilakos JP, Tomai MA. The use of Toll-like receptor 7/8 agonists as vaccine adjuvants. Expert Rev Vaccines 2014; 12:809-19. [DOI: 10.1586/14760584.2013.811208] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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42
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Perspectives in vaccine adjuvants for allergen-specific immunotherapy. Immunol Lett 2013; 161:207-10. [PMID: 24361819 DOI: 10.1016/j.imlet.2013.12.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/13/2013] [Indexed: 12/22/2022]
Abstract
The design of more powerful adjuvants is a tool of crucial interest to ameliorate vaccination strategies to reduce injections and/or dose of antigen, induce local immunity and obtain better protection. Effective anti-infectious vaccines should elicit protective TH1 responses, cytotoxic CD8+ cells and antibody-forming cells. However, cytokine microenvironment is a key point also in targeted therapeutic vaccinations, such as allergen-specific immunotherapy, where the interference with an already-existing but inappropriate immunity is required. In this case, safe, appropriately conditioning and potentially orally available adjuvants together with delivery to appropriate subsets of dendritic cells would be highly appreciated to properly boost innate immune cells. In fact, aluminium hydroxide, although safe, has been classically associated with the induction of a TH2 response to co-formulated antigens. Thus, detoxified lipopolysaccaride (MPL-A), CpG oligonucleotides, imidazoquinolines and adenine derivatives acting via innate sensors may represent improvements in therapeutic vaccinations for allergy as able to interfere with pathogenic TH2 cells with eventual induction of TH1 differentiation.
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Kokatla HP, Sil D, Malladi SS, Balakrishna R, Hermanson AR, Fox LM, Wang X, Dixit A, David SA. Exquisite selectivity for human toll-like receptor 8 in substituted furo[2,3-c]quinolines. J Med Chem 2013; 56:6871-85. [PMID: 23899291 DOI: 10.1021/jm400694d] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Toll-like receptor (TLR)-8 agonists activate adaptive immune responses by inducing robust production of T helper 1-polarizing cytokines, suggesting that TLR8-active compounds may be promising candidate adjuvants. We synthesized and evaluated hitherto unexplored furo[2,3-c]quinolines and regioisomeric furo[3,2-c]quinolines derived via a tandem, one-pot Sonogashira coupling and intramolecular 5-endo-dig cyclization strategy in a panel of primary screens. We observed a pure TLR8-agonistic activity profile in select furo[2,3-c]quinolines, with maximal potency conferred by a C2-butyl group (EC50 = 1.6 μM); shorter, longer, or substituted homologues as well as compounds bearing C1 substitutions were inactive, which was rationalized by docking studies using the recently described crystal structure of human TLR8. The best-in-class compound displayed prominent proinflammatory cytokine induction (including interleukin-12 and interleukin-18), but was bereft of interferon-α inducing properties, confirming its high selectivity for human TLR8.
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Affiliation(s)
- Hari Prasad Kokatla
- Department of Medicinal Chemistry and ‡Genomics Facility, University of Kansas , Lawrence, Kansas 66047, United States
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44
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Salunke DB, Connelly SW, Shukla NM, Hermanson AR, Fox LM, David SA. Design and development of stable, water-soluble, human Toll-like receptor 2 specific monoacyl lipopeptides as candidate vaccine adjuvants. J Med Chem 2013; 56:5885-900. [PMID: 23795818 PMCID: PMC3844559 DOI: 10.1021/jm400620g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Antigens in modern subunit vaccines are largely soluble and poorly immunogenic proteins inducing relatively short-lived immune responses. Appropriate adjuvants initiate early innate immune responses, amplifying subsequent adaptive immune responses. Agonists of Toll-like receptor 2 (TLR2) are devoid of significant proinflammatory activity in ex vivo human blood models and yet are potently adjuvantic, suggesting that this chemotype may be a safe and effective adjuvant. Our earlier work on the monoacyl lipopeptide class of TLR2 agonists led to the design of a highly potent lead but with negligible aqueous solubility, necessitating the reintroduction of aqueous solubility. We explored several strategies of introducing ionizable groups on the lipopeptide, as well as the systematic evaluation of chemically stable bioisosteres of the ester-linked palmitoyl group. These studies have led to a fully optimized, chemically stable, and highly water-soluble human TLR2-specific agonist, which was found to have an excellent safety profile and displayed prominent adjuvantic activities in rabbit models.
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Affiliation(s)
| | | | | | | | - Lauren M. Fox
- Department of Medicinal Chemistry, University of Kansas
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45
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Kokatla HP, Yoo E, Salunke DB, Sil D, Ng CF, Balakrishna R, Malladi SS, Fox LM, David SA. Toll-like receptor-8 agonistic activities in C2, C4, and C8 modified thiazolo[4,5-c]quinolines. Org Biomol Chem 2013; 11:1179-98. [PMID: 23314908 PMCID: PMC3577938 DOI: 10.1039/c2ob26705e] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Toll-like receptor (TLR)-8 agonists typified by the 2-alkylthiazolo[4,5-c]quinolin-4-amine (CL075) chemotype are uniquely potent in activating adaptive immune responses by inducing robust production of T helper 1-polarizing cytokines, suggesting that TLR8-active compounds could be promising candidate vaccine adjuvants, especially for neonatal vaccines. Alkylthiazoloquinolines with methyl, ethyl, propyl and butyl groups at C2 displayed comparable TLR8-agonistic potencies; activity diminished precipitously in the C2-pentyl compound, and higher homologues were inactive. The C2-butyl compound was unique in possessing substantial TLR7-agonistic activity. Analogues with branched alkyl groups at C2 displayed poor tolerance of terminal steric bulk. Virtually all modifications at C8 led to abrogation of agonistic activity. Alkylation on the C4-amine was not tolerated, whereas N-acyl analogues with short acyl groups (other than acetyl) retained TLR8 agonistic activity, but were substantially less water-soluble. Immunization in rabbits with a model subunit antigen adjuvanted with the lead C2-butyl thiazoloquinoline showed enhancements of antigen-specific antibody titers.
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Affiliation(s)
- Hari Prasad Kokatla
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Euna Yoo
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Deepak B. Salunke
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Diptesh Sil
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Cameron F. Ng
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Rajalakshmi Balakrishna
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Subbalakshmi S. Malladi
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Lauren M. Fox
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence KS 66047
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46
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Moyle PM, Toth I. Modern subunit vaccines: development, components, and research opportunities. ChemMedChem 2013; 8:360-76. [PMID: 23316023 DOI: 10.1002/cmdc.201200487] [Citation(s) in RCA: 310] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/08/2012] [Indexed: 12/11/2022]
Abstract
Traditional vaccines, based on the administration of killed or attenuated microorganisms, have proven to be among the most effective methods for disease prevention. Safety issues related to administering these complex mixtures, however, prevent their universal application. Through identification of the microbial components responsible for protective immunity, vaccine formulations can be simplified, enabling molecular-level vaccine characterization, improved safety profiles, prospects to develop new high-priority vaccines (e.g. for HIV, tuberculosis, and malaria), and the opportunity for extensive vaccine component optimization. This subunit approach, however, comes at the expense of decreased immunity, requiring the addition of immunostimulatory agents (adjuvants). As few adjuvants are currently used in licensed vaccines, adjuvant development represents an exciting area for medicinal chemists to play a role in the future of vaccine development. In addition, immune responses can be further customized though optimization of delivery systems, tuning the size of particulate vaccines, targeting specific cells of the immune system (e.g. dendritic cells), and adding components to aid vaccine efficacy in whole immunized populations (e.g. promiscuous T-helper epitopes). Herein we review the current state of the art and future direction in subunit vaccine development, with a focus on the described components and their potential to steer the immune response toward a desired response.
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Affiliation(s)
- Peter Michael Moyle
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD 4072, Australia.
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47
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Yoo E, Crall BM, Balakrishna R, Malladi SS, Fox LM, Hermanson AR, David SA. Structure–activity relationships in Toll-like receptor 7 agonistic 1H-imidazo[4,5-c]pyridines. Org Biomol Chem 2013; 11:6526-45. [DOI: 10.1039/c3ob40816g] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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48
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Salunke DB, Yoo E, Shukla NM, Balakrishna R, Malladi SS, Serafin KJ, Day VW, Wang X, David SA. Structure-activity relationships in human Toll-like receptor 8-active 2,3-diamino-furo[2,3-c]pyridines. J Med Chem 2012; 55:8137-51. [PMID: 22924757 DOI: 10.1021/jm301066h] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In our ongoing search toward identifying novel and synthetically simpler candidate vaccine adjuvants, we hypothesized that the imidazo[1,2-a]pyrazines, readily accessible via the Groebke-Blackburn-Bienaymé multicomponent reaction, would possess sufficient structural similarity with TLR7/8-agonistic imidazoquinolines. With pyridoxal as the aldehyde component, furo[2,3-c]pyridines, rather than the expected imidazo[1,2-a]pyridines, were obtained, which were characterized by NMR spectroscopy and crystallography. Several analogues were found to activate TLR8-dependent NF-κB signaling. In a focused library of furo[2,3-c]pyridines, a distinct SAR was observed with varying substituents at C2. In human PBMCs, none of the furo[2,3-c]pyridines showed any proinflammatory cytokine induction but upregulated several chemokine ligand genes. In immunization studies in rabbits, the most active compound showed prominent adjuvantic effects. The complete lack of proinflammatory cytokine induction coupled with strong adjuvantic activity of the novel furo[2,3-c]pyridines render this hitherto unknown chemotype an attractive class of compounds which are expected to be devoid of local or systemic reactogenicity.
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Affiliation(s)
- Deepak B Salunke
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Room 320D, 2030 Becker Drive, Lawrence, Kansas 66047, USA
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Shukla NM, Salunke DB, Balakrishna R, Mutz CA, Malladi SS, David SA. Potent adjuvanticity of a pure TLR7-agonistic imidazoquinoline dendrimer. PLoS One 2012; 7:e43612. [PMID: 22952720 PMCID: PMC3429503 DOI: 10.1371/journal.pone.0043612] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 07/26/2012] [Indexed: 01/25/2023] Open
Abstract
Engagement of toll-like receptors (TLRs) serve to link innate immune responses with adaptive immunity and can be exploited as powerful vaccine adjuvants for eliciting both primary and anamnestic immune responses. TLR7 agonists are highly immunostimulatory without inducing dominant proinflammatory cytokine responses. We synthesized a dendrimeric molecule bearing six units of a potent TLR7/TLR8 dual-agonistic imidazoquinoline to explore if multimerization of TLR7/8 would result in altered activity profiles. A complete loss of TLR8-stimulatory activity with selective retention of the TLR7-agonistic activity was observed in the dendrimer. This was reflected by a complete absence of TLR8-driven proinflammatory cytokine and interferon (IFN)-γ induction in human PBMCs, with preservation of TLR7-driven IFN-α induction. The dendrimer was found to be superior to the imidazoquinoline monomer in inducing high titers of high-affinity antibodies to bovine α-lactalbumin. Additionally, epitope mapping experiments showed that the dendrimer induced immunoreactivity to more contiguous peptide epitopes along the amino acid sequence of the model antigen.
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Affiliation(s)
- Nikunj M. Shukla
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Deepak B. Salunke
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Rajalakshmi Balakrishna
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Cole A. Mutz
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Subbalakshmi S. Malladi
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas, United States of America
- * E-mail:
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50
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TLR7 Recognition Is Dispensable for Influenza Virus A Infection but Important for the Induction of Hemagglutinin-Specific Antibodies in Response to the 2009 Pandemic Split Vaccine in Mice. J Virol 2012; 86:10988-98. [DOI: 10.1128/jvi.01064-12] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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