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D'Oro U, O'Hagan DT. The scientific journey of a novel adjuvant (AS37) from bench to bedside. NPJ Vaccines 2024; 9:26. [PMID: 38332005 PMCID: PMC10853242 DOI: 10.1038/s41541-024-00810-6] [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: 07/02/2023] [Accepted: 01/24/2024] [Indexed: 02/10/2024] Open
Abstract
A decade ago, we described a new approach to discover next generation adjuvants, identifying small-molecule immune potentiators (SMIPs) as Toll-like receptor (TLR)7 agonists. We also optimally formulated these drugs through adsorption to aluminum salts (alum), allowing them to be evaluated with a range of established and early-stage vaccines. Early proof-of-concept studies showed that a TLR7 agonist (TLR7a)-based SMIP, when adsorbed to alum, could perform as an effective adjuvant for a variety of different antigens, in both small and large animals. Studies in rodents demonstrated that the adjuvant enhanced immunogenicity of a recombinant protein-based vaccine against Staphylococcus aureus, and also showed potential to improve existing vaccines against pertussis or meningococcal infection. Extensive evaluations showed that the adjuvant was effective in non-human primates (NHPs), exploiting a mechanism of action that was consistent across the different animal models. The adjuvant formulation (named AS37) has now been advanced into clinical evaluation. A systems biology-based evaluation of the phase I clinical data with a meningococcal C conjugate vaccine showed that the AS37-adjuvanted formulation had an acceptable safety profile, was potent, and activated the expected immune pathways in humans, which was consistent with observations from the NHP studies. In the intervening decade, several alternative TLR7 agonists have also emerged and advanced into clinical development, such as the alum adsorbed TLR7/8 SMIP present in a widely distributed COVID-19 vaccine. This review summarizes the research and early development of the new adjuvant AS37, with an emphasis on the steps taken to allow its progression into clinical evaluations.
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Siena E, Schiavetti F, Borgogni E, Taccone M, Faenzi E, Brazzoli M, Aprea S, Bardelli M, Volpini G, Buricchi F, Sammicheli C, Tavarini S, Bechtold V, Blohmke CJ, Cardamone D, De Intinis C, Gonzalez-Lopez A, O'Hagan DT, Nuti S, Seidl C, Didierlaurent AM, Bertholet S, D'Oro U, Medini D, Finco O. Systems analysis of human responses to an aluminium hydroxide-adsorbed TLR7 agonist (AS37) adjuvanted vaccine reveals a dose-dependent and specific activation of the interferon-mediated antiviral response. Vaccine 2023; 41:724-734. [PMID: 36564274 DOI: 10.1016/j.vaccine.2022.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022]
Abstract
The candidate Adjuvant System AS37 contains a synthetic toll-like receptor agonist (TLR7a) adsorbed to alum. In a phase I study (NCT02639351), healthy adults were randomised to receive one dose of licensed alum-adjuvanted meningococcal serogroup C (MenC-CRM197) conjugate vaccine (control) or MenC-CRM197 conjugate vaccine adjuvanted with AS37 (TLR7a dose 12.5, 25, 50 or 100 µg). A subset of 66 participants consented to characterisation of peripheral whole blood transcriptomic responses, systemic cytokine/chemokine responses and multiple myeloid and lymphoid cell responses as exploratory study endpoints. Blood samples were collected pre-vaccination, 6 and 24 h post-vaccination, and 3, 7, 28 and 180 days post-vaccination. The gene expression profile in whole blood showed an early, AS37-specific transcriptome response that peaked at 24 h, increased with TLR7a dose up to 50 µg and generally resolved within one week. Five clusters of differentially expressed genes were identified, including those involved in the interferon-mediated antiviral response. Evaluation of 30 cytokines/chemokines by multiplex assay showed an increased level of interferon-induced chemokine CXCL10 (IP-10) at 24 h and 3 days post-vaccination in the AS37-adjuvanted vaccine groups. Increases in activated plasmacytoid dendritic cells (pDC) and intermediate monocytes were detected 3 days post-vaccination in the AS37-adjuvanted vaccine groups. T follicular helper (Tfh) cells increased 7 days post-vaccination and were maintained at 28 days post-vaccination, particularly in the AS37-adjuvanted vaccine groups. Moreover, most of the subjects that received vaccine containing 25, 50 and 100 µg TLR7a showed an increased MenC-specific memory B cell responses versus baseline. These data show that the adsorption of TLR7a to alum promotes an immune signature consistent with TLR7 engagement, with up-regulation of interferon-inducible genes, cytokines and frequency of activated pDC, intermediate monocytes, MenC-specific memory B cells and Tfh cells. TLR7a 25-50 µg can be considered the optimal dose for AS37, particularly for the adjuvanted MenC-CRM197 conjugate vaccine.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Carlo De Intinis
- GSK, Via Fiorentina 1, 53100 Siena, Italy; University of Turin, Via Verdi 8, 10124 Torino, Italy.
| | | | | | - Sandra Nuti
- GSK, 14200 Shady Grove Rd, Rockville MD, USA.
| | | | | | | | - Ugo D'Oro
- GSK, Via Fiorentina 1, 53100 Siena, Italy.
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Jia JZ, Tan CW, Cheng SMS, Gu H, Yeoh AYY, Mok CKP, Wang Y, Zhao J, Leung NHL, Cowling BJ, Poon LLM, Hui DSC, Wang L, Peiris M, Valkenburg SA. Priming conditions shape breadth of neutralizing antibody responses to sarbecoviruses. Nat Commun 2022; 13:6285. [PMID: 36271047 PMCID: PMC9586968 DOI: 10.1038/s41467-022-34038-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/10/2022] [Indexed: 12/25/2022] Open
Abstract
Vaccines that are broadly cross-protective against current and future SARS-CoV-2 variants of concern (VoC) or across the sarbecoviruses subgenus remain a priority for public health. Virus neutralization is the best available correlate of protection. To define the magnitude and breadth of cross-neutralization in individuals with different exposure to SARS-CoV-2 infection and vaccination, we here use a multiplex surrogate neutralization assay based on virus spike receptor binding domains of multiple SARS-CoV-2 VoC, as well as related bat and pangolin viruses. We include sera from cohorts of individuals vaccinated with two or three doses of mRNA (BNT162b2) or inactivated SARS-CoV-2 (Coronavac or Sinopharm) vaccines with or without a history of previous SARS-CoV-2 or SARS-CoV-1 infection. SARS-CoV-2 or SARS-CoV-1 infection followed by BNT162b2 vaccine, Omicron BA.2 breakthrough infection following BNT162b2 vaccine or a third dose of BNT162b2 following two doses of BNT162b2 or Coronavac elicit the highest and broadest neutralization across VoCs. For both breadth and magnitude of neutralization across all sarbecoviruses, those infected with SARS-CoV-1 immunized with BNT162b2 outperform all other combinations of infection and/or vaccination. These data may inform vaccine design strategies for generating broadly neutralizing antibodies to SARS-CoV-2 variants or across the sarbecovirus subgenus.
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Affiliation(s)
- Janice Zhirong Jia
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Chee Wah Tan
- Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Samuel M S Cheng
- School of Public Health, The University of Hong Kong, Hong Kong SAR, China
| | - Haogao Gu
- School of Public Health, The University of Hong Kong, Hong Kong SAR, China
| | | | - Chris Ka Pun Mok
- The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong SAR, China
- Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Yanqun Wang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jincun Zhao
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Nancy H L Leung
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Benjamin J Cowling
- WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Leo L M Poon
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- School of Public Health, The University of Hong Kong, Hong Kong SAR, China
- Centre for Immunology and Infection (C2I), Hong Kong Science Park, Hong Kong SAR, China
| | - David S C Hui
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong SAR, China
- Stanley Ho Centre for Emerging Infectious Diseases, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Linfa Wang
- Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Malik Peiris
- School of Public Health, The University of Hong Kong, Hong Kong SAR, China
- Centre for Immunology and Infection (C2I), Hong Kong Science Park, Hong Kong SAR, China
| | - Sophie A Valkenburg
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia.
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Wei H, Xie H, Qu J, Xie A, Xie S, Huang H, Li J, Fang C, Shi F, Qiu H, Qi Y, Tian X, Yang Q, Huang J. TLR7 modulating B-cell immune responses in the spleen of C57BL/6 mice infected with Schistosoma japonicum. PLoS Negl Trop Dis 2021; 15:e0009943. [PMID: 34788282 PMCID: PMC8598019 DOI: 10.1371/journal.pntd.0009943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/21/2021] [Indexed: 11/19/2022] Open
Abstract
B cells played an important role in Schistosoma infection-induced diseases. TLR7 is an intracellular member of the innate immune receptor. The role of TLR7 on B cells mediated immune response is still unclear. Here, C57BL/6 mice were percutaneously infected by S. japonicum for 5-6 weeks. The percentages and numbers of B cells increased in the infected mice (p < 0.05), and many activation and function associated molecules were also changed on B cells. More splenic cells of the infected mice expressed TLR7, and B cells were served as the main cell population. Moreover, a lower level of soluble egg antigen (SEA) specific antibody and less activation associated molecules were found on the surface of splenic B cells from S. japonicum infected TLR7 gene knockout (TLR7 KO) mice compared to infected wild type (WT) mice (p < 0.05). Additionally, SEA showed a little higher ability in inducing the activation of B cells from naive WT mice than TLR7 KO mice (p < 0.05). Finally, the effects of TLR7 on B cells are dependent on the activation of NF-κB p65. Altogether, TLR7 was found modulating the splenic B cell responses in S. japonicum infected C57BL/6 mice.
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Affiliation(s)
- Haixia Wei
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Hongyan Xie
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jiale Qu
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Anqi Xie
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Shihao Xie
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - He Huang
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jiajie Li
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Chao Fang
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Feihu Shi
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Huaina Qiu
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yanwei Qi
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xu Tian
- Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & The Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
- * E-mail: (XT); (QY); (JH)
| | - Quan Yang
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- * E-mail: (XT); (QY); (JH)
| | - Jun Huang
- Key Laboratory of Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- China Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, China
- * E-mail: (XT); (QY); (JH)
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Shi Y. PLAN B for immunotherapy: Promoting and leveraging anti-tumor B cell immunity. J Control Release 2021; 339:156-163. [PMID: 34563591 DOI: 10.1016/j.jconrel.2021.09.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 09/19/2021] [Accepted: 09/21/2021] [Indexed: 12/19/2022]
Abstract
Current immuno-oncology primarily focuses on adaptive cellular immunity mediated by T lymphocytes. The other important lymphocytes, B cells, are largely ignored in cancer immunotherapy. B cells are generally considered to be responsible for humoral immune response to viral and bacterial infections. The role of B cells in cancer immunity has long been under debate. Recently, increasing evidence from both preclinical and clinical research has shown that B cells can also induce potent anti-cancer immunity, via humoral and cellular immune responses. Yet it is unclear how to efficiently integrate B cell immunity in cancer immunotherapy. In the current perspective, anti-tumor immunity of B cells is discussed regarding antibody production, antigen presentation, cytokine release and contribution to intratumoral tertiary lymphoid structures. Afterwards, immunosuppressive regulatory phenotypes of B cells are summarized. Furthermore, strategies to activate and modulate B cells using nanomedicines and biomaterials are discussed. This article provides a unique perspective on "PLAN B" (promoting and leveraging anti-tumor B cell immunity) using nanomedicines and biomaterials for cancer immunotherapy. This is envisaged to form a new research direction with the potential to reach the next breakthrough in immunotherapy.
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Affiliation(s)
- Yang Shi
- Institute for Experimental Molecular Imaging, Uniklinik RWTH Aachen and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen 52074, Germany.
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Saito T, Sako Y, Sato-Kaneko F, Hosoya T, Yao S, Lao FS, Shpigelman J, Messer K, Pu M, Shukla NM, Chan M, Chu PJ, Cottam HB, Hayashi T, Carson DA, Corr M. Small Molecule Potentiator of Adjuvant Activity Enhancing Survival to Influenza Viral Challenge. Front Immunol 2021; 12:701445. [PMID: 34650551 PMCID: PMC8505803 DOI: 10.3389/fimmu.2021.701445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 08/30/2021] [Indexed: 01/02/2023] Open
Abstract
As viruses continue to mutate the need for rapid high titer neutralizing antibody responses has been highlighted. To meet these emerging threats, agents that enhance vaccine adjuvant activity are needed that are safe with minimal local or systemic side effects. To respond to this demand, we sought small molecules that would sustain and improve the protective effect of a currently approved adjuvant, monophosphoryl lipid A (MPLA), a Toll-like receptor 4 (TLR4) agonist. A lead molecule from a high-throughput screen, (N-(4-(2,5-dimethylphenyl)thiazol-2-yl)-4-(piperidin-1-ylsulfonyl)benzamide, was identified as a hit compound that sustained NF-κB activation by a TLR4 ligand, lipopolysaccharide (LPS), after an extended incubation (16 h). In vitro, the resynthesized compound (2D216) enhanced TLR4 ligand-induced innate immune activation and antigen presenting function in primary murine bone marrow-derived dendritic cells without direct activation of T cells. In vivo murine vaccination studies demonstrated that compound 2D216 acted as a potent co-adjuvant when used in combination with MPLA that enhanced antigen-specific IgG equivalent to that of AS01B. The combination adjuvant MPLA/2D216 produced Th1 dominant immune responses and importantly protected mice from lethal influenza virus challenge. 2D216 alone or 2D216/MPLA demonstrated minimal local reactogenicity and no systemic inflammatory response. In summary, 2D216 augmented the beneficial protective immune responses of MPLA as a co-adjuvant and showed an excellent safety profile.
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Affiliation(s)
- Tetsuya Saito
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States.,Department of Rheumatology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Yukiya Sako
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Fumi Sato-Kaneko
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Tadashi Hosoya
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States.,Department of Rheumatology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Shiyin Yao
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Fitzgerald S Lao
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Jonathan Shpigelman
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Karen Messer
- The Herbert Wertheim School of Public Health and Longevity, University of California San Diego, La Jolla, CA, United States
| | - Minya Pu
- The Herbert Wertheim School of Public Health and Longevity, University of California San Diego, La Jolla, CA, United States
| | - Nikunj M Shukla
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Michael Chan
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Paul J Chu
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Howard B Cottam
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Tomoko Hayashi
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Dennis A Carson
- Moores Cancer Center, University of California San Diego, La Jolla, CA, United States
| | - Maripat Corr
- Department of Medicine, University of California San Diego, La Jolla, CA, United States
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Clemens EA, Alexander-Miller MA. Understanding Antibody Responses in Early Life: Baby Steps towards Developing an Effective Influenza Vaccine. Viruses 2021; 13:v13071392. [PMID: 34372597 PMCID: PMC8310046 DOI: 10.3390/v13071392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 07/13/2021] [Indexed: 01/01/2023] Open
Abstract
The immune system of young infants is both quantitatively and qualitatively distinct from that of adults, with diminished responsiveness leaving these individuals vulnerable to infection. Because of this, young infants suffer increased morbidity and mortality from respiratory pathogens such as influenza viruses. The impaired generation of robust and persistent antibody responses in these individuals makes overcoming this increased vulnerability through vaccination challenging. Because of this, an effective vaccine against influenza viruses in infants under 6 months is not available. Furthermore, vaccination against influenza viruses is challenging even in adults due to the high antigenic variability across viral strains, allowing immune evasion even after induction of robust immune responses. This has led to substantial interest in understanding how specific antibody responses are formed to variable and conserved components of influenza viruses, as immune responses tend to strongly favor recognition of variable epitopes. Elicitation of broadly protective antibody in young infants, therefore, requires that both the unique characteristics of young infant immunity as well as the antibody immunodominance present among epitopes be effectively addressed. Here, we review our current understanding of the antibody response in newborns and young infants and discuss recent developments in vaccination strategies that can modulate both magnitude and epitope specificity of IAV-specific antibody.
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Huang X, Zhang X, Lu M. Recent trends in the development of Toll-like receptor 7/8-targeting therapeutics. Expert Opin Drug Discov 2021; 16:869-880. [PMID: 33678093 DOI: 10.1080/17460441.2021.1898369] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Introduction: Toll-like receptor (TLR) 7 and TLR8 are functionally localized to endosomes and recognize specific RNA sequences. They play crucial roles in initiating innate and adaptive immune responses. TLR7/8 activation protects the host against invading pathogens and enhances immune responses. In contrast, sustained TLR7/8 signaling leads to immune overreaction. Therefore, agonists or antagonists targeting TLR7/8 signaling are favorable drug candidates for the treatment of immune disorders.Areas covered: Basic knowledge about TLR7 and TLR8 and their signaling pathways are briefly reviewed. Various therapeutic agents have been designed to activate or antagonize TLR7/8 signaling pathways, and their safety and efficacy for the treatment of multiple diseases have been investigated in preclinical animal models and clinical trials. TLR7/8 agonists exhibit potent antiviral activity and regulate anti-tumor immune responses. TLR7 agonists have also been used as adjuvants to improve vaccine immunogenicity and generate greater seroprotection. TLR7/8 antagonists are promising candidates for the treatment of autoimmune and inflammatory diseases.Expert opinion: TLR7/8 pathways are favorable targets for immunological therapies. Future research should concentrate on the optimization of drug safety, efficiency, and specificity. Detailed mechanistic studies will contribute to the development of TLR7/8 immunomodulators and novel therapeutic strategies.
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Affiliation(s)
- Xuan Huang
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaoyong Zhang
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Mengji Lu
- Institute of Virology, University Hospital of Essen, Essen, Germany
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George PJ, Tai W, Du L, Lustigman S. The Potency of an Anti-MERS Coronavirus Subunit Vaccine Depends on a Unique Combinatorial Adjuvant Formulation. Vaccines (Basel) 2020; 8:vaccines8020251. [PMID: 32471056 PMCID: PMC7350031 DOI: 10.3390/vaccines8020251] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/17/2020] [Accepted: 05/23/2020] [Indexed: 01/29/2023] Open
Abstract
Vaccination is one of the most successful strategies to prevent human infectious diseases. Combinatorial adjuvants have gained increasing interest as they can stimulate multiple immune pathways and enhance the vaccine efficacy of subunit vaccines. We investigated the adjuvanticity of Aluminum (alum) in combination with rASP-1, a protein adjuvant, using the Middle East respiratory syndrome coronavirus MERS-CoV receptor-binding-domain (RBD) vaccine antigen. A highly enhanced anti-MERS-CoV neutralizing antibody response was induced when mice were immunized with rASP-1 and the alum-adjuvanted RBD vaccine in two separate injection sites as compared to mice immunized with RBD + rASP-1 + alum formulated into a single inoculum. The antibodies produced also significantly inhibited the binding of RBD to its cell-associated receptor. Moreover, immunization with rASP-1 co-administered with the alum-adjuvanted RBD vaccine in separate sites resulted in an enhanced frequency of TfH and GC B cells within the draining lymph nodes, both of which were positively associated with the titers of the neutralizing antibody response related to anti-MERS-CoV protective immunity. Our findings not only indicate that this unique combinatorial adjuvanted RBD vaccine regimen improved the immunogenicity of RBD, but also point to the importance of utilizing combinatorial adjuvants for the induction of synergistic protective immune responses.
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Affiliation(s)
- Parakkal Jovvian George
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA;
| | - Wanbo Tai
- Laboratory of Viral Immunology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA; (W.T.); (L.D.)
| | - Lanying Du
- Laboratory of Viral Immunology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA; (W.T.); (L.D.)
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA;
- Correspondence:
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Gao W, Sun X, Li D, Sun L, He Y, Wei H, Jin F, Cao Y. Toll-like receptor 7 and Toll-like receptor 9 agonists effectively enhance immunological memory in Plasmodium chabaudi infected BALB/c mice. Int Immunopharmacol 2020; 81:106248. [PMID: 32007799 DOI: 10.1016/j.intimp.2020.106248] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 11/29/2022]
Affiliation(s)
- Wenyan Gao
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China; Department of Obstetrics, The First Hospital of China Medical University, Shenyang 110001, Liaoning, China
| | - Xiaodan Sun
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China
| | - Danni Li
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China
| | - Lin Sun
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China
| | - Yang He
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China
| | - Huanping Wei
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China
| | - Feng Jin
- Department of Breast Surgery, The First Hospital of China Medical University, Shenyang 110001, Liaoning, China
| | - Yaming Cao
- Department of Immunology, Basic Medicine College of China Medical University, Shenyang 110122, Liaoning, China.
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11
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Gestal MC, Johnson HM, Harvill ET. Immunomodulation as a Novel Strategy for Prevention and Treatment of Bordetella spp. Infections. Front Immunol 2019; 10:2869. [PMID: 31921136 PMCID: PMC6923730 DOI: 10.3389/fimmu.2019.02869] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/22/2019] [Indexed: 12/13/2022] Open
Abstract
Well-adapted pathogens have evolved to survive the many challenges of a robust immune response. Defending against all host antimicrobials simultaneously would be exceedingly difficult, if not impossible, so many co-evolved organisms utilize immunomodulatory tools to subvert, distract, and/or evade the host immune response. Bordetella spp. present many examples of the diversity of immunomodulators and an exceptional experimental system in which to study them. Recent advances in this experimental system suggest strategies for interventions that tweak immunity to disrupt bacterial immunomodulation, engaging more effective host immunity to better prevent and treat infections. Here we review advances in the understanding of respiratory pathogens, with special focus on Bordetella spp., and prospects for the use of immune-stimulatory interventions in the prevention and treatment of infection.
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Affiliation(s)
- Monica C Gestal
- Department of Infectious Diseases, College of Veterinary Sciences, University of Georgia, Athens, GA, United States
| | - Hannah M Johnson
- Department of Infectious Diseases, College of Veterinary Sciences, University of Georgia, Athens, GA, United States
| | - Eric T Harvill
- Department of Infectious Diseases, College of Veterinary Sciences, University of Georgia, Athens, GA, United States
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Adjuvant effect of TLR7 agonist adsorbed on aluminum hydroxide (AS37): A phase I randomized, dose escalation study of an AS37-adjuvanted meningococcal C conjugated vaccine. Clin Immunol 2019; 209:108275. [PMID: 31669193 DOI: 10.1016/j.clim.2019.108275] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 08/02/2019] [Accepted: 10/17/2019] [Indexed: 02/06/2023]
Abstract
An adjuvant system (AS37) has been developed containing a synthetic toll-like receptor agonist (TLR7a). We conducted a phase I randomized, observer-blind, dose-escalation study to assess the safety and immunogenicity of an investigational AS37-adjuvanted meningococcus C (MenC) conjugate vaccine in healthy adults (NCT02639351). A control group received a licensed MenC conjugate alum-adjuvanted vaccine. Eighty participants were randomized to receive one dose of control or investigational vaccine containing AS37 (TLR7a dose 12.5, 25, 50, 100 μg). All vaccines were well tolerated, apart from in the TLR7a 100 μg dose group, which had three reports (18.8%) of severe systemic adverse events. Four weeks after vaccination, human complement serum bactericidal assay seroresponse rates against MenC were 56-81% in all groups, and ELISA seroresponses were ≥81% for all AS37-adjuvanted vaccine groups (100% in 50 and 100 μg dose groups) and 88% in the control group. Antibody responses were maintained at six months after vaccination.
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Khezri P, Shahabi S, Abasi E, Hajipirloo HM. Comparison of immunogenical potency of Leishmania major (MRHO/IR/75/ER) antigens prepared by 3 different methods in conjunction with Alum-Naltrexone adjuvant in BALB/c mice. ALEXANDRIA JOURNAL OF MEDICINE 2019. [DOI: 10.1016/j.ajme.2018.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Peyman Khezri
- Cellular and Molecular Research Center, Department of Parasitology and Mycology, School of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | - Shahram Shahabi
- Cellular and Molecular Research Center, Department of Immunology, School of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | - Esmaeil Abasi
- Cellular and Molecular Research Center, Department of Parasitology and Mycology, School of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | - Habib Mohammadzadeh Hajipirloo
- Cellular and Molecular Research Center, Department of Parasitology and Mycology, School of Medicine, Urmia University of Medical Sciences, Urmia, Iran
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14
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Shi S, Zhu H, Xia X, Liang Z, Ma X, Sun B. Vaccine adjuvants: Understanding the structure and mechanism of adjuvanticity. Vaccine 2019; 37:3167-3178. [PMID: 31047671 DOI: 10.1016/j.vaccine.2019.04.055] [Citation(s) in RCA: 240] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 04/02/2019] [Accepted: 04/18/2019] [Indexed: 12/16/2022]
Abstract
In conjugate, inactivated, recombinant, and toxoid vaccines, adjuvants are extensively and essentially used for enhanced and long-lasting protective immune responses. Depending on the type of diseases and immune responses required, adjuvants with different design strategies are developed. With aluminum salt-based adjuvants as the most used ones in commercial vaccines, other limited adjuvants, e.g., AS01, AS03, AS04, CpG ODN, and MF59, are used in FDA-approved vaccines for human use. In this paper, we review the uses of different adjuvants in vaccines including the ones used in FDA-approved vaccines and vaccines under clinical investigations. We discuss how adjuvants with different formulations could affect the magnitude and quality of adaptive immune response for optimized protection against specific pathogens. We emphasize the molecular mechanisms of various adjuvants, with the aim to establish structure-activity relationships (SARs) for designing more effective and safer adjuvants for both preventative and therapeutic vaccines.
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Affiliation(s)
- Shuting Shi
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China
| | - Haoru Zhu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China
| | - Xinyu Xia
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China
| | - Zhihui Liang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China
| | - Xuehu Ma
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China
| | - Bingbing Sun
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China; School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, 116024 Dalian, China.
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15
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Krueger CC, Thoms F, Keller E, Leoratti FMS, Vogel M, Bachmann MF. RNA and Toll-Like Receptor 7 License the Generation of Superior Secondary Plasma Cells at Multiple Levels in a B Cell Intrinsic Fashion. Front Immunol 2019; 10:736. [PMID: 31024563 PMCID: PMC6467167 DOI: 10.3389/fimmu.2019.00736] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/19/2019] [Indexed: 12/14/2022] Open
Abstract
Secondary plasma cells (PCs) originate from memory B cells and produce increased levels of antibodies with higher affinity compared to PCs generated during primary responses. Here we demonstrate that virus-like particles (VLPs) only induce secondary PCs in the presence of toll-like receptor (TLR) 7 and if they are loaded with RNA. Furthermore, adoptive transfer experiments demonstrate that RNA and TLR7 signaling are required for secondary PC generation, both at the level of memory B cell as well as PC differentiation. TLR7-signaling occurred in a B cell intrinsic manner as TLR7-deficient B cells in an otherwise TLR7-competent environment failed to differentiate into secondary PCs. Therefore, RNA inside VLPs is essential for the generation of memory B cells, which are competent to differentiate to secondary PCs and for the differentiation of secondary PCs themselves. While we have not tested all other TLR or non-TLR adjuvants with our VLPs, these data have obvious implications for vaccine design, as RNA packaged into VLPs is a simple way to enhance induction of memory B cells capable of generating secondary PCs.
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Affiliation(s)
- Caroline C. Krueger
- Department of BioMedical Research, University of Bern, Bern, Switzerland
- Department of Immunology RIA, University Hospital Bern, Bern, Switzerland
| | - Franziska Thoms
- Department of Dermatology, University Hospital Zurich, Schlieren, Switzerland
| | - Elsbeth Keller
- Department of BioMedical Research, University of Bern, Bern, Switzerland
- Department of Immunology RIA, University Hospital Bern, Bern, Switzerland
| | - Fabiana M. S. Leoratti
- Department of BioMedical Research, University of Bern, Bern, Switzerland
- Department of Immunology RIA, University Hospital Bern, Bern, Switzerland
| | - Monique Vogel
- Department of BioMedical Research, University of Bern, Bern, Switzerland
- Department of Immunology RIA, University Hospital Bern, Bern, Switzerland
| | - Martin F. Bachmann
- Department of BioMedical Research, University of Bern, Bern, Switzerland
- Department of Immunology RIA, University Hospital Bern, Bern, Switzerland
- Nuffield Department of Medicine, The Henry Wellcome Building for Molecular Physiology, The Jenner Institute, University of Oxford, Oxford, United Kingdom
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16
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Liu Z, Chen J, Li W, Bi Y, Li Y, Fan M. Identification of FimH derivatives as adjuvant vaccinated with PAc that enhance protection against Streptcoccus mutans colonization. Mol Cell Probes 2019; 45:19-25. [PMID: 30940544 DOI: 10.1016/j.mcp.2019.03.009] [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: 02/19/2019] [Revised: 03/27/2019] [Accepted: 03/27/2019] [Indexed: 10/27/2022]
Abstract
FimH is the adhesin of type I fimbriae expressed on Escherichia coli that can mediate specific adherence to host cells. High binding mutations in FimH are related to the adaptive evolution of bacteria. However, additional roles that these allelic variations may play remain elusive. To investigate novel biological functions of the mutations in FimH, we introduced four different variants of FimH by incorporating single amino acid substitutions at specific sites, namely A25P, G73R, A106, and T158P, respectively. In this study, adjuvant potential of FimH variants was evaluated by investigating their ability to trigger innate immune response to DC2.4 and adaptive immunity to improve immunological characteristics. The data revealed that purified A106 and T158P up-regulated the expression of co-stimulatory molecules critically involved in DC2.4 activation by interaction with TLR4, whereas A25P and G73R did not induce the phenotypic maturation of DC2.4. Besides, the culture of DC2.4 with A106 and T158P enhanced the release of cytokines and protein phagocytosis. When formulated with PAc, T158P elicited more robust PAc-specific IgG and IgA antibody responses compared to PBS, PAc and PAc+K12 groups and inhibited bacteria colonization. Collectively, the results confirmed that the T158P mutation located around the inter-domain interface of the protein induced a specific enhancement effect on adjuvant characteristics.
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Affiliation(s)
- Zhongfang Liu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China
| | - Junlan Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China
| | - Wuyou Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China
| | - Yongli Bi
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China
| | - Yuhong Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China.
| | - Mingwen Fan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine of Ministry of Education (KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, 430079, China.
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