1
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Jensen SB, Jæhger DE, Serrano-Chávez E, Halldórsdóttir HR, Engel TB, Jørgensen JS, Björgvinsdóttir UJ, Kostrikov S, Scheeper MJ, Ringgaard L, Bruun LM, Stavnsbjerg C, Christensen E, Bak M, Thuroczy J, Balogh L, Jensen ATI, Melander F, Kjaer A, Henriksen JR, Hansen AE, Andresen TL. An in situ depot for the sustained release of a TLR7/8 agonist in combination with a TGFβ inhibitor promotes anti-tumor immune responses. Nat Commun 2024; 15:7687. [PMID: 39227589 PMCID: PMC11371921 DOI: 10.1038/s41467-024-50967-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 07/26/2024] [Indexed: 09/05/2024] Open
Abstract
Cancer curing immune responses against heterogeneous solid cancers require that a coordinated immune activation is initiated in the antigen avid but immunosuppressive tumor microenvironment (TME). The plastic TME, and the poor systemic tolerability of immune activating drugs are, however, fundamental barriers to generating curative anticancer immune responses. Here, we introduce the CarboCell technology to overcome these barriers by forming an intratumoral sustained drug release depot that provides high payloads of immune stimulatory drugs selectively within the TME. The CarboCell thereby induces a hot spot for immune cell training and polarization and further drives and maintains the tumor-draining lymph nodes in an anticancer and immune activated state. Mechanistically, this transforms cancerous tissues, consequently generating systemic anticancer immunoreactivity. CarboCell can be injected through standard thin-needle technologies and has inherent imaging contrast which secure accurate intratumoral positioning. In particular, here we report the therapeutic performance for a dual-drug CarboCell providing sustained release of a Toll-like receptor 7/8 agonist and a transforming growth factor-β inhibitor in preclinical tumor models in female mice.
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Affiliation(s)
- Sophie B Jensen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ditte E Jæhger
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Elizabeth Serrano-Chávez
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Hólmfríður R Halldórsdóttir
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Trine B Engel
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Jennifer S Jørgensen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Unnur J Björgvinsdóttir
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Serhii Kostrikov
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Marouschka J Scheeper
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Lars Ringgaard
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Linda M Bruun
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Camilla Stavnsbjerg
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Esben Christensen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Martin Bak
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | | | - Andreas T I Jensen
- Department of Health Technology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Roskilde, Denmark
| | - Fredrik Melander
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Andreas Kjaer
- Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital, Copenhagen, Denmark
- Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas R Henriksen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Anders E Hansen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Thomas L Andresen
- Department of Health Technology, Biotherapeutic Engineering and Drug Targeting, Technical University of Denmark, Kgs. Lyngby, Denmark.
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2
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Alsaiari SK, Nadeef S, Daristotle JL, Rothwell W, Du B, Garcia J, Zhang L, Sarmadi M, Forster TA, Menon N, Lin SQ, Tostanoski LH, Hachmann N, Wang EY, Ventura JD, Barouch DH, Langer R, Jaklenec A. Zeolitic imidazolate frameworks activate endosomal Toll-like receptors and potentiate immunogenicity of SARS-CoV-2 spike protein trimer. SCIENCE ADVANCES 2024; 10:eadj6380. [PMID: 38446889 PMCID: PMC10917347 DOI: 10.1126/sciadv.adj6380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 01/30/2024] [Indexed: 03/08/2024]
Abstract
Nanomaterials offer unique opportunities to engineer immunomodulatory activity. In this work, we report the Toll-like receptor agonist activity of a nanoscale adjuvant zeolitic imidazolate framework-8 (ZIF-8). The accumulation of ZIF-8 in endosomes and the pH-responsive release of its subunits enable selective engagement with endosomal Toll-like receptors, minimizing the risk of off-target activation. The intrinsic adjuvant properties of ZIF-8, along with the efficient delivery and biomimetic presentation of a severe acute respiratory syndrome coronavirus 2 spike protein receptor-binding domain trimer, primed rapid humoral and cell-mediated immunity in a dose-sparing manner. Our study offers insights for next-generation adjuvants that can potentially impact future vaccine development.
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Affiliation(s)
- Shahad K. Alsaiari
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Seba Nadeef
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - John L. Daristotle
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - William Rothwell
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Bujie Du
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Johnny Garcia
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Linzixuan Zhang
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Morteza Sarmadi
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Timothy A. Forster
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Nandita Menon
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Stacey Qiaohui Lin
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Lisa H. Tostanoski
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Nicole Hachmann
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Erika Yan Wang
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - John D. Ventura
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Dan H. Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Robert Langer
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ana Jaklenec
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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3
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Strašek Benedik N, Dolšak A, Švajger U, Sosič I, Gobec S, Sova M. Structural Optimization and Biological Evaluation of Isoxazolo[5,4 -d]pyrimidines as Selective Toll-Like Receptor 7 Agonists. ACS OMEGA 2024; 9:2362-2382. [PMID: 38250345 PMCID: PMC10795023 DOI: 10.1021/acsomega.3c06343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/30/2023] [Accepted: 12/12/2023] [Indexed: 01/23/2024]
Abstract
Toll-like receptors (TLRs) are components of innate immunity that play a crucial role in several diseases, including chronic inflammatory and infectious diseases, autoimmune diseases, and cancer. In particular, TLR7 has been identified as a key player in the innate immune response against viral infections and small-molecule TLR7 agonists have shown potential for vaccine therapy, for treatment of asthma and allergies, and as anticancer drugs. Inspired by our previous discovery of selective TLR7 agonists, our goal was to develop and introduce a new chemotype of TLR7 agonists by replacing the quinazoline ring with a new heterocycle isoxazolo[5,4-d]pyrimidine. Here, we report design, optimized synthesis, and structure-activity relationship studies of a novel class of TLR7 agonists based on the 6-(trifluoromethyl)isoxazolo[5,4-d]pyrimidine-4-amine scaffold that demonstrate high selectivity and low micromolar potencies. The best-in-class agonist 21a, with an EC50 value of 7.8 μM, also proved to be noncytotoxic and induced secretion of cytokines, including IL-1β, IL-12p70, IL-8, and TNF-α, indicating its potential to modulate the immune response.
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Affiliation(s)
- Nika Strašek Benedik
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
| | - Ana Dolšak
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
| | - Urban Švajger
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
- Blood
Transfusion Centre of Slovenia, Šlajmerjeva 6, Ljubljana 1000, Slovenia
| | - Izidor Sosič
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
| | - Stanislav Gobec
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
| | - Matej Sova
- Faculty
of Pharmacy, Department of Pharmaceutical Chemistry, University of Ljubljana, Aškerčeva 7, Ljubljana 1000, Slovenia
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4
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Yuen MF, Balabanska R, Cottreel E, Chen E, Duan D, Jiang Q, Patil A, Triyatni M, Upmanyu R, Zhu Y, Canducci F, Gane EJ. TLR7 agonist RO7020531 versus placebo in healthy volunteers and patients with chronic hepatitis B virus infection: a randomised, observer-blind, placebo-controlled, phase 1 trial. THE LANCET. INFECTIOUS DISEASES 2023; 23:496-507. [PMID: 36509100 DOI: 10.1016/s1473-3099(22)00727-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Toll-like receptor 7 (TLR7) agonists augment immune activity and have potential for the treatment of chronic hepatitis B virus (HBV) infection. We aimed to assess the safety and tolerability of RO7020531 (also called RG7854), a prodrug of the TLR7 agonist RO7011785, in healthy volunteers and patients with chronic HBV infection. METHODS This randomised, observer-blind, placebo-controlled, phase 1 study was done in two parts. Part 1 was done at one site in New Zealand and part 2 was done at 12 sites in Bulgaria, Hong Kong, Italy, New Zealand, the Netherlands, Taiwan, Thailand, and the UK. In part 1, healthy volunteers were randomly assigned (4:1) within one of eight dose cohorts (3 mg, 10 mg, 20 mg, 40 mg, 60 mg, 100 mg, 140 mg, or 170 mg) to receive a single RO7020531 dose or placebo or randomly assigned (4:1) within one of three dose cohorts (100 mg, 140 mg, or 170 mg) to receive either RO7020531 or placebo every other day for 13 days. In part 2, nucleoside or nucleotide analogue-suppressed patients with chronic HBV infection were randomly assigned (4:1) within cohorts 1-3 (150 mg, 150 mg, or 170 mg) to receive either RO7020531 or placebo and treatment-naive patients with chronic HBV infection were randomly assigned (3:1) in cohort 4 to receive either 150 mg of RO7020531 or placebo. Patients were treated every other day for 6 weeks. Study medication was administered orally to participants after they had fasted. Study participants and investigational staff were masked to treatment allocation. The primary outcome was the safety and tolerability of RO7020531, as measured by the incidence and severity of adverse events and the incidence of laboratory, vital sign, and electrocardiogram abnormalities, and was analysed in all participants who received at least one dose of the study medication. This trial is registered with ClinicalTrials.gov, NCT02956850, and the study is complete. FINDINGS Between Dec 12, 2016, and March 21, 2021, 340 healthy volunteers were screened in part 1, of whom 80 were randomly assigned in the single ascending dose study (eight assigned RO7020531 in each cohort and 16 assigned placebo) and 30 were randomly assigned in the multiple ascending dose study (eight assigned RO7020531 in each cohort and six assigned placebo), and 110 patients were screened in part 2, of whom 30 were randomly assigned in cohorts 1-3 (16 assigned RO7020531 150 mg, eight assigned RO7020531 170 mg, and six assigned placebo) and 20 were randomly assigned in cohort 4 (15 assigned RO7020531 and five assigned placebo). All randomly assigned participants received at least one dose of a study drug and were included in the safety analysis. All tested doses of RO7020531 were safe and had acceptable tolerability in healthy volunteers and patients. The most frequent treatment-related adverse events among the total study population were headache (15 [9%] of 160 participants), influenza-like illness (seven [4%] of 160 participants), and pyrexia (ten [6%] of 160 participants). Most adverse events were mild and transient. There were no severe or serious adverse events in healthy volunteers. In the patient cohorts, there was one severe adverse event (influenza-like illness with 170 mg of RO7020531) and one serious adverse event (moderate influenza-like illness with a 3-day hospitalisation in a treatment-naive patient receiving RO7020531). There were no treatment-related deaths. INTERPRETATION Due to acceptable safety and tolerability, RO7020531 should continue to be developed for the treatment of patients with chronic HBV infection. FUNDING F Hoffmann-La Roche.
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Affiliation(s)
- Man-Fung Yuen
- Department of Medicine, Queen Mary Hospital, School of Clinical Medicine and State Key Laboratory of Liver Research, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Rozalina Balabanska
- Clinic of Gastroenterology, Acibadem City Clinic Tokuda Hospital, Sofia, Bulgaria
| | - Emmanuelle Cottreel
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel, Switzerland
| | - Ethan Chen
- Roche Pharma Product Development China, Shanghai, China
| | - Dan Duan
- Roche Pharma Research and Early Development, Roche Innovation Center, Shanghai, China
| | - Qiudi Jiang
- Roche Pharma Research and Early Development, Roche Innovation Center, Shanghai, China
| | - Avinash Patil
- Product Development Data Science Department, Roche Products, Welwyn, UK
| | - Miriam Triyatni
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel, Switzerland
| | - Ruchi Upmanyu
- Product Development Data Science Department, Roche Products, Welwyn, UK
| | - Yonghong Zhu
- Roche Pharma Research and Early Development, Roche Innovation Center, Shanghai, China
| | - Filippo Canducci
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel, Switzerland.
| | - Edward J Gane
- Faculty of Medicine, University of Auckland, Auckland, New Zealand
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5
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Complexing CpG adjuvants with cationic liposomes enhances vaccine-induced formation of liver T RM cells. Vaccine 2023; 41:1094-1107. [PMID: 36609029 DOI: 10.1016/j.vaccine.2022.12.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 12/05/2022] [Accepted: 12/19/2022] [Indexed: 01/06/2023]
Abstract
Tissue resident memory T cells (TRM cells) can provide effective tissue surveillance and can respond rapidly to infection. Vaccination strategies aimed at generating TRM cells have shown promise against a range of pathogens. We have previously shown that the choice of adjuvant critically influences CD8+ TRM cell formation in the liver. However, the range of adjuvants tested was limited. Here, we assessed the ability of a broad range of adjuvants stimulating membrane (TLR4), endosomal (TLR3, TLR7 and TLR9) and cytosolic (cGAS, RIG-I) pathogen recognition receptors for their capacity to induce CD8+ TRM formation in a subunit vaccination model. We show that CpG oligodeoxynucleotides (ODN) remain the most efficient inducers of liver TRM cells among all adjuvants tested. Moreover, their combination with the cationic liposome DOTAP further enhances the potency, particularly of the class B ODN CpG 1668 and the human TLR9 ligand CpG 2006 (CpG 7909). This study informs the design of efficient liver TRM-based vaccines for their potential translation.
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6
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Veneziani I, Alicata C, Moretta L, Maggi E. The Latest Approach of Immunotherapy with Endosomal TLR Agonists Improving NK Cell Function: An Overview. Biomedicines 2022; 11:biomedicines11010064. [PMID: 36672572 PMCID: PMC9855813 DOI: 10.3390/biomedicines11010064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/05/2022] [Accepted: 12/08/2022] [Indexed: 12/29/2022] Open
Abstract
Toll-like receptors (TLRs) are the most well-defined pattern recognition receptors (PRR) of several cell types recognizing pathogens and triggering innate immunity. TLRs are also expressed on tumor cells and tumor microenvironment (TME) cells, including natural killer (NK) cells. Cell surface TLRs primarily recognize extracellular ligands from bacteria and fungi, while endosomal TLRs recognize microbial DNA or RNA. TLR engagement activates intracellular pathways leading to the activation of transcription factors regulating gene expression of several inflammatory molecules. Endosomal TLR agonists may be considered as new immunotherapeutic adjuvants for dendritic cell (DC) vaccines able to improve anti-tumor immunity and cancer patient outcomes. The literature suggests that endosomal TLR agonists modify TME on murine models and human cancer (clinical trials), providing evidence that locally infused endosomal TLR agonists may delay tumor growth and induce tumor regression. Recently, our group demonstrated that CD56bright NK cell subset is selectively responsive to TLR8 engagement. Thus, TLR8 agonists (loaded or not to nanoparticles or other carriers) can be considered a novel strategy able to promote anti-tumor immunity. TLR8 agonists can be used to activate and expand in vitro circulating or intra-tumoral NK cells to be adoptively transferred into patients.
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Affiliation(s)
- Irene Veneziani
- Translational Immunology Unit, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
| | - Claudia Alicata
- Tumor Immunology Unit, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
| | - Lorenzo Moretta
- Tumor Immunology Unit, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
| | - Enrico Maggi
- Translational Immunology Unit, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
- Correspondence:
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7
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Chaudhari S, D'Souza BM, Morales JY, Young-Stubbs CM, Shimoura CG, Ma R, Mathis KW. Renal TLR-7/TNF-α pathway as a potential female-specific mechanism in the pathogenesis of autoimmune-induced hypertension. Am J Physiol Heart Circ Physiol 2022; 323:H1331-H1342. [PMID: 36367687 PMCID: PMC9744658 DOI: 10.1152/ajpheart.00286.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 11/04/2022] [Accepted: 11/05/2022] [Indexed: 11/13/2022]
Abstract
Hypertension is prevalent in patients with systemic lupus erythematosus (SLE). The goal of the current study is to track the pathogenesis of hypertension and renal injury in SLE, identify contributory mechanisms, and highlight differences in disease development among sexes. Mean arterial pressure was measured in conscious male and female SLE (NZBWF1) and control (NZW) mice at 34-35 wk of age using indwelling arterial catheters. Measures of renal injury, renal inflammation, and renal hemodynamics were used to monitor the potential contributors to latent sex differences. Both male and female SLE mice were hypertensive at 35 wk of age, and the hypertension was linked to renal injury in females, but not in males. A known contributor of renal pathology in SLE, Toll-like receptor (TLR)-7, and its downstream effector, the proinflammatory cytokine tumor necrosis factor (TNF)-α, were lower in male SLE mice than in females. Male SLE mice also had higher glomerular filtration rate (GFR) and lower renal vascular resistance (RVR) than females. Our data suggest that although hypertension in female SLE mice is associated with renal mechanisms, hypertension in male SLE mice may develop independent of renal changes. Future studies will continue to dissect sex-specific factors that should be considered when treating patients with hypertension with underlying chronic inflammation and/or autoimmunity.NEW & NOTEWORTHY There is a high prevalence of hypertension in male and female SLE; however, male SLE mice are hypertensive without renal involvement. The development of hypertension in female SLE mice is renocentric and strongly associated with injurious renal mechanisms like the TLR-7→TNF-α pathway. This clear difference in the pathogenesis among the sexes could have a significant impact on how we treat patients with hypertension with underlying chronic autoimmune/inflammatory diseases.
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Affiliation(s)
- Sarika Chaudhari
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Bradley M D'Souza
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Jessica Y Morales
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Cassandra M Young-Stubbs
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Caroline G Shimoura
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Rong Ma
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Keisa W Mathis
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
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8
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Zhang J, Li Z, Chandrasekar A, Li S, Ludolph A, Boeckers TM, Huber-Lang M, Roselli F, Olde Heuvel F. Fast Maturation of Splenic Dendritic Cells Upon TBI Is Associated With FLT3/FLT3L Signaling. Front Immunol 2022; 13:824459. [PMID: 35281004 PMCID: PMC8907149 DOI: 10.3389/fimmu.2022.824459] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/31/2022] [Indexed: 12/29/2022] Open
Abstract
The consequences of systemic inflammation are a significant burden after traumatic brain injury (TBI), with almost all organs affected. This response consists of inflammation and concurrent immunosuppression after injury. One of the main immune regulatory organs, the spleen, is highly interactive with the brain. Along this brain–spleen axis, both nerve fibers as well as brain-derived circulating mediators have been shown to interact directly with splenic immune cells. One of the most significant comorbidities in TBI is acute ethanol intoxication (EI), with almost 40% of patients showing a positive blood alcohol level (BAL) upon injury. EI by itself has been shown to reduce proinflammatory mediators dose-dependently and enhance anti-inflammatory mediators in the spleen. However, how the splenic immune modulatory effect reacts to EI in TBI remains unclear. Therefore, we investigated early splenic immune responses after TBI with and without EI, using gene expression screening of cytokines and chemokines and fluorescence staining of thin spleen sections to investigate cellular mechanisms in immune cells. We found a strong FLT3/FLT3L induction 3 h after TBI, which was enhanced by EI. The FLT3L induction resulted in phosphorylation of FLT3 in CD11c+ dendritic cells, which enhanced protein synthesis, maturation process, and the immunity of dendritic cells, shown by pS6, peIF2A, MHC-II, LAMP1, and CD68 by immunostaining and TNF-α expression by in-situ hybridization. In conclusion, these data indicate that TBI induces a fast maturation and immunity of dendritic cells which is associated with FLT3/FLT3L signaling and which is enhanced by EI prior to TBI.
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Affiliation(s)
- Jin Zhang
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany
| | - Zhenghui Li
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany.,Department of Neurosurgery, Kaifeng Central Hospital, Kaifeng, China
| | - Akila Chandrasekar
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany
| | - Shun Li
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany
| | - Albert Ludolph
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany.,German Center for Neurodegenerative Diseases (DZNE) , Ulm, Germany
| | - Tobias Maria Boeckers
- German Center for Neurodegenerative Diseases (DZNE) , Ulm, Germany.,Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Markus Huber-Lang
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital, Ulm, Germany
| | - Francesco Roselli
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany.,German Center for Neurodegenerative Diseases (DZNE) , Ulm, Germany.,Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Florian Olde Heuvel
- Department of Neurology, Center for Biomedical Research (ZBMF), Ulm University, Ulm, Germany
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9
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Barati M, Mohebali M, Khamesipour A, Bahrami F, Darabi H, Khaze V, Riazi-Rad F, Habibi G, Ajdary S, Alimohammadian MH. Evaluation of Cellular Immune Responses in Dogs Immunized with Alum-Precipitated Autoclaved Leishmania major along with BCG and Imiquimod. IRANIAN JOURNAL OF PARASITOLOGY 2021; 16:348-356. [PMID: 34630579 PMCID: PMC8476724 DOI: 10.18502/ijpa.v16i3.7087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/05/2020] [Indexed: 11/24/2022]
Abstract
Background: We aimed to investigate the potential effects of BCG and imiquimod on improvement of current experimental L. major vaccine against dogs in an endemic area of Zoonotic visceral leishmaniasis (ZVL) in Iran. Methods: During 2012 till 2014, seven mixed-breed shepherd dogs with no anti-Leishmania antibodies and no response to Leishmanin reagent were immunized with 2 doses of alum-precipitated autoclaved L. major (Alum-AML) while BCG and imiquimod (for skin pre-treatment) were used as adjuvants. The productions of a few characteristic cytokines of T-helper immune responses and the development of delayed-type hypersensitivity (DTH) of the immunized animals were then evaluated, up to 300 days. Blood samples were collected at 0, 30, 80 and 300 d post-vaccination and the concentrations of IFN-γ, IL10, IL-12 and TGF-β cytokines secreted from PBMCs at these time-points were quantified by ELISA. DTH was evaluated by Leishmanin skin test (LST). Results: Although a similar LST conversion was observed at all time-points, the cytokine measurement results indicated significantly higher levels of IFN-γ at day 80 and elevated levels of IL-10 at days 80 and 300, post-vaccination. Moreover, a significantly higher IFN-γ/IL-10 ratio was observed at day 30 post-vaccination compared to the other time-points. Conclusion: Although a Th1-like response could be observed at day 30 post-vaccination, the development of cytokine profiles was inclined toward mixed Th1 and Th2 responses at days 80 and 300 post-vaccination. This situation may indicate the requirement of an additional boosting by this Alum-AML formula, in order to induce long-lasting protection against ZVL.
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Affiliation(s)
- Mohammad Barati
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | - Mehdi Mohebali
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Khamesipour
- Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, Tehran, Iran
| | - Fariborz Bahrami
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | - Haiedeh Darabi
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | - Vahid Khaze
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | - Farhad Riazi-Rad
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | | | - Soheila Ajdary
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
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10
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Bhagchandani S, Johnson JA, Irvine DJ. Evolution of Toll-like receptor 7/8 agonist therapeutics and their delivery approaches: From antiviral formulations to vaccine adjuvants. Adv Drug Deliv Rev 2021; 175:113803. [PMID: 34058283 PMCID: PMC9003539 DOI: 10.1016/j.addr.2021.05.013] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 05/04/2021] [Accepted: 05/15/2021] [Indexed: 02/07/2023]
Abstract
Imidazoquinoline derivatives (IMDs) and related compounds function as synthetic agonists of Toll-like receptors 7 and 8 (TLR7/8) and one is FDA approved for topical antiviral and skin cancer treatments. Nevertheless, these innate immune system-activating drugs have potentially much broader therapeutic utility; they have been pursued as antitumor immunomodulatory agents and more recently as candidate vaccine adjuvants for cancer and infectious disease. The broad expression profiles of TLR7/8, poor pharmacokinetic properties of IMDs, and toxicities associated with systemic administration, however, are formidable barriers to successful clinical translation. Herein, we review IMD formulations that have advanced to the clinic and discuss issues related to biodistribution and toxicity that have hampered the further development of these compounds. Recent strategies aimed at enhancing safety and efficacy, particularly through the use of bioconjugates and nanoparticle formulations that alter pharmacokinetics, biodistribution, and cellular targeting, are described. Finally, key aspects of the biology of TLR7 signaling, such as TLR7 tolerance, that may need to be considered in the development of new IMD therapeutics are discussed.
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Affiliation(s)
- Sachin Bhagchandani
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
| | - Jeremiah A Johnson
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA.
| | - Darrell J Irvine
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA.
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11
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Qiu CC, Kotredes KP, Cremers T, Patel S, Afanassiev A, Slifker M, Gallucci S, Gamero AM. Targeted Stat2 deletion in conventional dendritic cells impairs CTL responses but does not affect antibody production. Oncoimmunology 2020; 10:1860477. [PMID: 33457079 PMCID: PMC7781843 DOI: 10.1080/2162402x.2020.1860477] [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] [Indexed: 11/21/2022] Open
Abstract
STAT2 is a central component of the ISGF3 transcriptional complex downstream of type I interferon (IFN-I) signaling. The significance of in vivo IFN-I/STAT1 signals in cDCs is well-established in the generation of antitumor cytotoxic T cell (CTL) responses. However, the role of STAT2 has remained elusive. Here, we report a clinical correlation between cDC markers and STAT2 associated with better survival in human metastatic melanoma. In a murine tumor transplantation model, targeted Stat2 deletion in CD11c+cDCs enhanced tumor growth unaffected by IFNβ therapy. Furthermore, STAT2 was essential for both, the activation of CD8a+cDCs and CD11b+cDCs and antigen cross-presentation in vivo for the generation of robust T cell killing response. In contrast, STAT2 in CD11c+cDCs was dispensable for stimulating an antigen-specific humoral response, which was impaired in global Stat2 deficient mice. Thus, our studies indicate that STAT2 in cDCs is critical in host IFN-I signals by sculpting CTL responses against tumors.
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Affiliation(s)
- Connie C Qiu
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Kevin P Kotredes
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Tess Cremers
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Sajan Patel
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Alexandra Afanassiev
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Michael Slifker
- Biostatistics and Bioinformatics Facility, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Stefania Gallucci
- Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Ana M Gamero
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA.,Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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12
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Vinod N, Hwang D, Azam SH, Van Swearingen AED, Wayne E, Fussell SC, Sokolsky-Papkov M, Pecot CV, Kabanov AV. High-capacity poly(2-oxazoline) formulation of TLR 7/8 agonist extends survival in a chemo-insensitive, metastatic model of lung adenocarcinoma. SCIENCE ADVANCES 2020; 6:eaba5542. [PMID: 32596460 PMCID: PMC7299629 DOI: 10.1126/sciadv.aba5542] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 05/06/2020] [Indexed: 05/03/2023]
Abstract
About 40% of patients with non-small cell lung cancer (NSCLC) have stage IV cancer at the time of diagnosis. The only viable treatment options for metastatic disease are systemic chemotherapy and immunotherapy. Nonetheless, chemoresistance remains a major cause of chemotherapy failure. New immunotherapeutic modalities such as anti-PD-1 immune checkpoint blockade have shown promise; however, response to such strategies is highly variable across patients. Here, we show that our unique poly(2-oxazoline)-based nanomicellar formulation (PM) of Resiquimod, an imidazoquinoline Toll-like receptor (TLR) 7/8 agonist, had a superior tumor inhibitory effect in a metastatic model of lung adenocarcinoma, relative to anti-PD-1 therapy or platinum-based chemotherapy. Investigation of the in vivo immune status following Resiquimod PM treatment showed that Resiquimod-based stimulation of antigen-presenting cells in the tumor microenvironment resulted in the mobilization of an antitumor CD8+ immune response. Our study demonstrates the promise of poly(2-oxazoline)-formulated Resiquimod for treating metastatic NSCLC.
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Affiliation(s)
- Natasha Vinod
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
- Joint UNC/NC State Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599-7575, USA
| | - Duhyeong Hwang
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Salma H. Azam
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Amanda E. D. Van Swearingen
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Wayne
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Sloane Christian Fussell
- Department of Biology, Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marina Sokolsky-Papkov
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Chad V. Pecot
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Division of Hematology and Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Alexander V. Kabanov
- Center for Nanotechnology in Drug Delivery and Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
- Laboratory of Chemical Design of Bionanomaterials, Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119992, Russia
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13
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Combination of Mycobacterium indicus pranii and Heat-Induced Promastigotes Cures Drug-Resistant Leishmania Infection: Critical Role of Interleukin-6-Producing Classical Dendritic Cells. Infect Immun 2020; 88:IAI.00222-19. [PMID: 32229617 DOI: 10.1128/iai.00222-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/24/2020] [Indexed: 12/18/2022] Open
Abstract
The major issues in available therapeutic modalities against leishmaniasis are cost, toxicity, and the emergence of drug resistance. The aim of this work was to develop a successful therapeutic adjuvant against drug-resistant Leishmania donovani infection by means of combining Mycobacterium indicus pranii with heat-induced promastigotes (HIP). One-month postinfected BALB/c mice were administered subcutaneously with M. indicus pranii (108 cells) and HIP (100 μg) for 5 days. Spleens were harvested for flow cytometric and reverse transcriptase PCR analysis. The antileishmanial effect of the combination strategy was associated with induction of a disease-resolving Th1 and Th17 response with simultaneous downregulation of CD4+ CD25+ Foxp3+ (nTreg) cells and CD4+ CD25- Foxp3- (Tr1) cells in the spleen. The significant expansion of CD4+ TCM (CD4+ CD44hi CD11ahi CD62Lhi) cells was a further interesting outcome of this therapeutic strategy in the context of long-term protection of hosts against secondary infection. Toll-like receptor 2 (TLR2) was also found instrumental in this antiparasitic therapy. Induced interleukin-6 (IL-6) production from expanded CD11c+ CD8α+ (cDC1) and CD11c+ CD11b+ (cDC2) dendritic cells (DCs) but not from the CD11b+ Ly6c+ inflammatory monocytes (iMOs), was found critical in the protective expansion of Th17 as evidenced by an in vivo IL-6 neutralization assay. It also promoted the hematopoietic conversion toward DC progenitors (pre-DCs) from common dendritic cell progenitors (CDPs), the immediate precursors, in bone marrow. This novel combinational strategy demonstrated that expansion of Th17 by IL-6 released from CD11c+ classical DCs is crucial, together with the conventional Th1 response, to control drug-resistant infection.
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14
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Wilkinson A, Lattmann E, Roces CB, Pedersen GK, Christensen D, Perrie Y. Lipid conjugation of TLR7 agonist Resiquimod ensures co-delivery with the liposomal Cationic Adjuvant Formulation 01 (CAF01) but does not enhance immunopotentiation compared to non-conjugated Resiquimod+CAF01. J Control Release 2018; 291:1-10. [PMID: 30291987 DOI: 10.1016/j.jconrel.2018.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Revised: 09/30/2018] [Accepted: 10/01/2018] [Indexed: 01/12/2023]
Abstract
Pattern recognition receptors, including the Toll-like receptors (TLRs), are important in the induction and activation of two critical arms of the host defence to pathogens and microorganisms: the rapid innate immune response (as characterised by the production of Th1 promoting cytokines and type 1 interferons) and the adaptive immune response. Through this activation, ligands and agonists of TLRs can enhance immunotherapeutic efficacy. Resiquimod is a small (water-soluble) agonist of the endosome-located Toll-like receptors 7 and 8 (TLR7/8). However due to its molecular attributes it rapidly distributes throughout the body after injection. To circumvent this, these TLR agonists can be incorporated within delivery systems, such as liposomes, to promote the co-delivery of both antigen and agonists to antigen presenting cells. In this present study, resiquimod has been chemically conjugated to a lipid to form a lipid-TLR7/8 agonist conjugate which can be incorporated within immunogenic cationic liposomes composed of dimethyldioctadecylammonium bromide (DDA) and the immunostimulatory glycolipid trehalose 6,6' - dibehenate (TDB). This DDA:TDB-TLR7/8 formulation offers similar vesicle characteristics to DDA:TDB (size and charge) and offers high retention of both resiquimod and the electrostatically adsorbed TB subunit antigen Ag85B-ESAT6-Rv2660c (H56). Following immunisation through the intramuscular (i.m.) route, these cationic DDA:TDB-TLR7/8 liposomes form a vaccine depot at the injection site. However, immunisation studies have shown that this biodistribution does not translate into notably increased antibody nor Th1 responses at the spleen and draining popliteal lymph node compared to DDA:TDB liposomes. This work demonstrates that the conjugation of TLR7/8 agonists to cationic liposomes can promote co-delivery but the immune responses stimulated do not merit the added complexity considerations of the formulation.
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Affiliation(s)
| | - Eric Lattmann
- School of Life and Health Sciences, Aston University, Birmingham, UK
| | - Carla B Roces
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow G4 0RE, UK
| | - Gabriel K Pedersen
- Department of Infectious Disease Immunology, Statens Serum Institute, Copenhagen, Denmark
| | - Dennis Christensen
- Department of Infectious Disease Immunology, Statens Serum Institute, Copenhagen, Denmark
| | - Yvonne Perrie
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral St, Glasgow G4 0RE, UK.
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15
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Abhyankar MM, Orr MT, Lin S, Suraju MO, Simpson A, Blust M, Pham T, Guderian JA, Tomai MA, Elvecrog J, Pedersen K, Petri WA, Fox CB. Adjuvant composition and delivery route shape immune response quality and protective efficacy of a recombinant vaccine for Entamoeba histolytica. NPJ Vaccines 2018; 3:22. [PMID: 29900011 PMCID: PMC5988657 DOI: 10.1038/s41541-018-0060-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 04/26/2018] [Accepted: 05/03/2018] [Indexed: 12/20/2022] Open
Abstract
Amebiasis caused by Entamoeba histolytica is the third leading cause of parasitic mortality globally, with some 100,000 deaths annually, primarily among young children. Protective immunity to amebiasis is associated with fecal IgA and IFN-γ in humans; however, no vaccine exists. We have previously identified recombinant LecA as a potential protective vaccine antigen. Here we describe the development of a stable, manufacturable PEGylated liposomal adjuvant formulation containing two synthetic Toll-like receptor (TLR) ligands: GLA (TLR4) and 3M-052 (TLR7/8). The liposomes stimulated production of monocyte/macrophage chemoattractants MCP-1 and Mip-1β, and Th1-associated cytokines IL-12p70 and IFN-γ from human whole blood dependent on TLR ligand composition and dose. The liposomes also demonstrated acceptable physicochemical compatibility with the recombinant LecA antigen. Whereas mice immunized with LecA and GLA-liposomes demonstrated enhanced antigen-specific fecal IgA titers, mice immunized with LecA and 3M-052-liposomes showed a stronger Th1 immune profile. Liposomes containing GLA and 3M-052 together elicited both LecA-specific fecal IgA and Th1 immune responses. Furthermore, the quality of the immune response could be modulated with modifications to the liposomal formulation based on PEG length. Compared to subcutaneous administration, the optimized liposome adjuvant composition with LecA antigen administered intranasally resulted in significantly enhanced fecal IgA, serum IgG2a, as well as systemic IFN-γ and IL-17A levels in mice. The optimized intranasal regimen provided greater than 80% protection from disease as measured by parasite antigen in the colon. This work demonstrates the physicochemical and immunological characterization of an optimized mucosal adjuvant system containing a combination of TLR ligands with complementary activities and illustrates the importance of adjuvant composition and route of delivery to enhance a multifaceted and protective immune response to amebiasis.
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Affiliation(s)
- Mayuresh M. Abhyankar
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA USA
| | - Mark T. Orr
- IDRI, 1616 Eastlake Ave E, Seattle, WA USA
- Department of Global Health, University of Washington, Seattle, WA USA
| | - Susan Lin
- IDRI, 1616 Eastlake Ave E, Seattle, WA USA
| | - Mohammed O. Suraju
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA USA
| | | | | | - Tiep Pham
- IDRI, 1616 Eastlake Ave E, Seattle, WA USA
| | | | - Mark A. Tomai
- 3M Drug Delivery Systems, 3M Center, 275-3E-10, St. Paul, MN USA
| | - James Elvecrog
- 3M Drug Delivery Systems, 3M Center, 275-3E-10, St. Paul, MN USA
| | | | - William A. Petri
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA USA
| | - Christopher B. Fox
- IDRI, 1616 Eastlake Ave E, Seattle, WA USA
- Department of Global Health, University of Washington, Seattle, WA USA
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16
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Kilgore AM, Welsh S, Cheney EE, Chitrakar A, Blain TJ, Kedl BJ, Hunter CA, Pennock ND, Kedl RM. IL-27p28 Production by XCR1 + Dendritic Cells and Monocytes Effectively Predicts Adjuvant-Elicited CD8 + T Cell Responses. Immunohorizons 2018; 2:1-11. [PMID: 29354801 PMCID: PMC5771264 DOI: 10.4049/immunohorizons.1700054] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
It is well accepted that the innate response is a necessary prerequisite to the formation of the adaptive response. This is true for T cell responses against infections or adjuvanted subunit vaccination. However, specific innate parameters with predictive value for the magnitude of an adjuvant-elicited T cell response have yet to be identified. We previously reported how T cell responses induced by subunit vaccination were dependent on the cytokine IL-27. These findings were unexpected, given that T cell responses to an infection typically increase in the absence of IL-27. Using a novel IL-27p28-eGFP reporter mouse, we now show that the degree to which an adjuvant induces IL-27p28 production from dendritic cells and monocytes directly predicts the magnitude of the T cell response elicited. To our knowledge, these data are the first to identify a concrete innate correlate of vaccine-elicited cellular immunity, and they have significant practical and mechanistic implications for subunit vaccine biology.
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Affiliation(s)
- Augustus M Kilgore
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Seth Welsh
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Elizabeth E Cheney
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Alisha Chitrakar
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Trevor J Blain
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Benjamin J Kedl
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
| | - Chris A Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Nathan D Pennock
- Department of Cell, Developmental & Cancer Biology, Oregon Health & Science University, Portland, OR 97239
| | - Ross M Kedl
- Department of Immunology and Microbiology, School of Medicine, University of Colorado Denver at Anschutz Medical Campus, Denver, CO 80045
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de Groot AM, Platteel ACM, Kuijt N, van Kooten PJS, Vos PJ, Sijts AJAM, van der Maaden K. Nanoporous Microneedle Arrays Effectively Induce Antibody Responses against Diphtheria and Tetanus Toxoid. Front Immunol 2017; 8:1789. [PMID: 29375544 PMCID: PMC5770646 DOI: 10.3389/fimmu.2017.01789] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 11/29/2017] [Indexed: 01/06/2023] Open
Abstract
The skin is immunologically very potent because of the high number of antigen-presenting cells in the dermis and epidermis, and is therefore considered to be very suitable for vaccination. However, the skin's physical barrier, the stratum corneum, prevents foreign substances, including vaccines, from entering the skin. Microneedles, which are needle-like structures with dimensions in the micrometer range, form a relatively new approach to circumvent the stratum corneum, allowing for minimally invasive and pain-free vaccination. In this study, we tested ceramic nanoporous microneedle arrays (npMNAs), representing a novel microneedle-based drug delivery technology, for their ability to deliver the subunit vaccines diphtheria toxoid (DT) and tetanus toxoid (TT) intradermally. First, the piercing ability of the ceramic (alumina) npMNAs, which contained over 100 microneedles per array, a length of 475 µm, and an average pore size of 80 nm, was evaluated in mouse skin. Then, the hydrodynamic diameters of DT and TT and the loading of DT, TT, and imiquimod into, and subsequent release from the npMNAs were assessed in vitro. It was shown that DT and TT were successfully loaded into the tips of the ceramic nanoporous microneedles, and by using near-infrared fluorescently labeled antigens, we found that DT and TT were released following piercing of the antigen-loaded npMNAs into ex vivo murine skin. Finally, the application of DT- and TT-loaded npMNAs onto mouse skin in vivo led to the induction of antigen-specific antibodies, with titers similar to those obtained upon subcutaneous immunization with a similar dose. In conclusion, we show for the first time, the potential of npMNAs for intradermal (ID) immunization with subunit vaccines, which opens possibilities for future ID vaccination designs.
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Affiliation(s)
- Anne Marit de Groot
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Sciences, Utrecht University, Utrecht, Netherlands
| | - Anouk C. M. Platteel
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Sciences, Utrecht University, Utrecht, Netherlands
| | - Nico Kuijt
- MyLife Technologies, Leiden, Netherlands
| | - Peter J. S. van Kooten
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Sciences, Utrecht University, Utrecht, Netherlands
| | | | - Alice J. A. M. Sijts
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Sciences, Utrecht University, Utrecht, Netherlands
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19
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Lebold KM, Jacoby DB, Drake MG. Toll-Like Receptor 7-Targeted Therapy in Respiratory Disease. Transfus Med Hemother 2016; 43:114-9. [PMID: 27226793 DOI: 10.1159/000445324] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/09/2016] [Indexed: 01/01/2023] Open
Abstract
Allergic asthma and allergic rhinitis are inflammatory diseases of the respiratory tract characterized by an excessive type-2 T helper cell (Th2) immune response. Toll-like receptor 7 (TLR7) is a single-stranded viral RNA receptor expressed in the airway that initiates a Th1 immune response and has garnered interest as a novel therapeutic target for treatment of allergic airway diseases. In animal models, synthetic TLR7 agonists reduce airway hyperreactivity, eosinophilic inflammation, and airway remodeling while decreasing Th2-associated cytokines. Furthermore, activation of TLR7 rapidly relaxes airway smooth muscle via production of nitric oxide. Thus, TLR7 has dual bronchodilator and anti-inflammatory effects. Two TLR7 ligands with promising pharmacologic profiles have entered clinical trials for the treatment of allergic rhinitis. Moreover, TLR7 agonists are potential antiviral therapies against respiratory viruses. TLR7 agonists enhance influenza vaccine efficacy and also reduce viral titers when given during an active airway infection. In this review, we examine the current data supporting TLR7 as a therapeutic target in allergic airway diseases.
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Affiliation(s)
- Katie M Lebold
- Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, USA
| | - David B Jacoby
- Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, USA
| | - Matthew G Drake
- Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, USA
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20
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Leleux J, Atalis A, Roy K. Engineering immunity: Modulating dendritic cell subsets and lymph node response to direct immune-polarization and vaccine efficacy. J Control Release 2015; 219:610-621. [PMID: 26489733 DOI: 10.1016/j.jconrel.2015.09.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/25/2015] [Accepted: 09/28/2015] [Indexed: 12/23/2022]
Abstract
While successful vaccines have been developed against many pathogens, there are still many diseases and pathogenic infections that are highly evasive to current vaccination strategies. Thus, more sophisticated approaches to control the type and quality of vaccine-induced immune response must be developed. Dendritic cells (DCs) are the sentinels of the body and play a critical role in immune response generation and direction by bridging innate and adaptive immunity. It is now well recognized that DCs can be separated into many subgroups, each of which has a unique function. Better understanding of how various DC subsets, in lymphoid organs and in the periphery, can be targeted through controlled delivery; and how these subsets modulate and control the resulting immune response could greatly enhance our ability to develop new, effective vaccines against complex diseases. In this review, we provide an overview of DC subset biology and discuss current immunotherapeutic strategies that utilize DC targeting to modulate and control immune responses.
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Affiliation(s)
- Jardin Leleux
- The Wallace H. Coulter Dept. of Biomedical Engineering at Georgia Tech and Emory University and The Center for Immunoengineering at Georgia Tech, The Parker H. Petit Institute for Bioengineering and Biosciences Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Alexandra Atalis
- The Wallace H. Coulter Dept. of Biomedical Engineering at Georgia Tech and Emory University and The Center for Immunoengineering at Georgia Tech, The Parker H. Petit Institute for Bioengineering and Biosciences Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Krishnendu Roy
- The Wallace H. Coulter Dept. of Biomedical Engineering at Georgia Tech and Emory University and The Center for Immunoengineering at Georgia Tech, The Parker H. Petit Institute for Bioengineering and Biosciences Georgia Institute of Technology, Atlanta, GA 30332, United States.
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Wu X, Gowda NM, Gowda DC. Phagosomal Acidification Prevents Macrophage Inflammatory Cytokine Production to Malaria, and Dendritic Cells Are the Major Source at the Early Stages of Infection: IMPLICATION FOR MALARIA PROTECTIVE IMMUNITY DEVELOPMENT. J Biol Chem 2015; 290:23135-47. [PMID: 26240140 DOI: 10.1074/jbc.m115.671065] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Indexed: 12/15/2022] Open
Abstract
Inflammatory cytokines produced at the early stages of malaria infection contribute to shaping protective immunity and pathophysiology. To gain mechanistic insight into these processes, it is important to understand the cellular origin of cytokines because both cytokine input and cytokine-producing cells play key roles. Here, we determined cytokine responses by monocytes, macrophages, and dendritic cells (DCs) to purified Plasmodium falciparum and Plasmodium berghei ANKA, and by spleen macrophages and DCs from Plasmodium yoelii 17NXL-infected and P. berghei ANKA-infected mice. The results demonstrate that monocytes and macrophages do not produce inflammatory cytokines to malaria parasites and that DCs are the primary source early in infection, and DC subsets differentially produce cytokines. Importantly, blocking of phagosomal acidification by inhibiting vacuolar-type H(+)-ATPase enabled macrophages to elicit cytokine responses. Because cytokine responses to malaria parasites are mediated primarily through endosomal Toll-like receptors, our data indicate that the inability of macrophages to produce cytokines is due to the phagosomal acidification that disrupts endosomal ligand-receptor engagement. Macrophages efficiently produced cytokines to LPS upon simultaneously internalizing parasites and to heat-killed Escherichia coli, demonstrating that phagosomal acidification affects endosomal receptor-mediated, but not cell surface receptor-mediated, recognition of Toll-like receptor agonists. Enabling monocytes/macrophages to elicit immune responses to parasites by blocking endosomal acidification can be a novel strategy for the effective development of protective immunity to malaria. The results have important implications for enhancing the efficacy of a whole parasite-based malaria vaccine and for designing strategies for the development of protective immunity to pathogens that induce immune responses primarily through endosomal receptors.
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Affiliation(s)
- Xianzhu Wu
- From the Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Nagaraj M Gowda
- From the Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - D Channe Gowda
- From the Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
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22
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Chistiakov DA, Sobenin IA, Orekhov AN, Bobryshev YV. Myeloid dendritic cells: Development, functions, and role in atherosclerotic inflammation. Immunobiology 2015; 220:833-44. [DOI: 10.1016/j.imbio.2014.12.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 12/07/2014] [Accepted: 12/22/2014] [Indexed: 12/21/2022]
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23
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Zhou ZX, Sun L. Immune effects of R848: evidences that suggest an essential role of TLR7/8-induced, Myd88- and NF-κB-dependent signaling in the antiviral immunity of Japanese flounder (Paralichthys olivaceus). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 49:113-20. [PMID: 25475963 DOI: 10.1016/j.dci.2014.11.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 11/26/2014] [Accepted: 11/26/2014] [Indexed: 06/04/2023]
Abstract
The imidazoquinoline compound R848 is a specific agonist of toll-like receptor (TLR) 7/TLR8 that has been used as an immunostimulant in humans against viral diseases. Although R848-induced immune response has been reported in teleost fish, the relevant mechanism is not clear. In this study, we investigated the antiviral potential and the signaling pathway of R848 in a model of Japanese flounder (Paralichthys olivaceus). We found that R848 was able to inhibit the replication of megalocytivirus, stimulated the proliferation of peripheral blood leukocytes (PBL), enhanced the expression of immune genes, and reduced apoptosis of PBL. When endosomal acidification was blocked by chloroquine (CQ), R848-mediated antiviral activity and immune response were significantly reduced. Likewise, inhibition of Myd88 activation markedly impaired the pro-proliferation and anti-apoptosis effect of R848. Cellular study showed that cultured founder cells treated with R848 exhibited augmented NF-κB activity, which, however, was dramatically reduced in the presence of CQ and Myd88 inhibitor. Furthermore, when NF-κB was inactivated, the effect of R848 on cell proliferation and apoptosis was significantly decreased. Taken together, these results indicate that R848 is an immunostimulant with antiviral property in a teleost species, and that the immune response of R848 is mediated by, most likely, TLR7/TLR8 signaling pathway, in which Myd88 and NK-κB play an essential role.
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Affiliation(s)
- Zhi-Xia Zhou
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China
| | - Li Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
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24
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Ilyinskii PO, Roy CJ, O'Neil CP, Browning EA, Pittet LA, Altreuter DH, Alexis F, Tonti E, Shi J, Basto PA, Iannacone M, Radovic-Moreno AF, Langer RS, Farokhzad OC, von Andrian UH, Johnston LPM, Kishimoto TK. Adjuvant-carrying synthetic vaccine particles augment the immune response to encapsulated antigen and exhibit strong local immune activation without inducing systemic cytokine release. Vaccine 2014; 32:2882-95. [PMID: 24593999 PMCID: PMC4059049 DOI: 10.1016/j.vaccine.2014.02.027] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Augmentation of immunogenicity can be achieved by particulate delivery of an antigen and by its co-administration with an adjuvant. However, many adjuvants initiate strong systemic inflammatory reactions in vivo, leading to potential adverse events and safety concerns. We have developed a synthetic vaccine particle (SVP) technology that enables co-encapsulation of antigen with potent adjuvants. We demonstrate that co-delivery of an antigen with a TLR7/8 or TLR9 agonist in synthetic polymer nanoparticles results in a strong augmentation of humoral and cellular immune responses with minimal systemic production of inflammatory cytokines. In contrast, antigen encapsulated into nanoparticles and admixed with free TLR7/8 agonist leads to lower immunogenicity and rapid induction of high levels of inflammatory cytokines in the serum (e.g., TNF-α and IL-6 levels are 50- to 200-fold higher upon injection of free resiquimod (R848) than of nanoparticle-encapsulated R848). Conversely, local immune stimulation as evidenced by cellular infiltration of draining lymph nodes and by intranodal cytokine production was more pronounced and persisted longer when SVP-encapsulated TLR agonists were used. The strong local immune activation achieved using a modular self-assembling nanoparticle platform markedly enhanced immunogenicity and was equally effective whether antigen and adjuvant were co-encapsulated in a single nanoparticle formulation or co-delivered in two separate nanoparticles. Moreover, particle encapsulation enabled the utilization of CpG oligonucleotides with the natural phosphodiester backbone, which are otherwise rapidly hydrolyzed by nucleases in vivo. The use of SVP may enable clinical use of potent TLR agonists as vaccine adjuvants for indications where cellular immunity or robust humoral responses are required.
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Affiliation(s)
| | | | | | | | | | | | - Frank Alexis
- Laboratory of Nanomedicine and Biomaterials, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Elena Tonti
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jinjun Shi
- Laboratory of Nanomedicine and Biomaterials, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Pamela A Basto
- David H. Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
| | - Matteo Iannacone
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aleksandar F Radovic-Moreno
- David H. Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
| | - Robert S Langer
- David H. Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
| | - Omid C Farokhzad
- Laboratory of Nanomedicine and Biomaterials, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Ulrich H von Andrian
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
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Stanley MA. The imidazoquinolines — mechanism of action and therapeutic potential in HPV-associated disease. ACTA ACUST UNITED AC 2013. [DOI: 10.1179/095741905x41267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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26
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Crespo MI, Zacca ER, Núñez NG, Ranocchia RP, Maccioni M, Maletto BA, Pistoresi-Palencia MC, Morón G. TLR7 triggering with polyuridylic acid promotes cross-presentation in CD8α+ conventional dendritic cells by enhancing antigen preservation and MHC class I antigen permanence on the dendritic cell surface. THE JOURNAL OF IMMUNOLOGY 2013; 190:948-60. [PMID: 23284054 DOI: 10.4049/jimmunol.1102725] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
ssRNA can interact with dendritic cells (DCs) through binding to TLR7, inducing secretion of proinflammatory cytokines and type I IFN. Triggering TLR7 enhances cross-priming of CD8(+) T cells, which requires cross-presentation of exogenous Ag to DCs. However, how TLR triggering can affect Ag cross-presentation is still not clear. Using OVA as an Ag model, we observed that stimulation of TLR7 in DCs by polyuridylic acid (polyU), a synthetic ssRNA analog, generates a strong specific cytotoxic response in C57BL/6 mice. PolyU stimulate CD8α(+) DCs to cross-prime naive CD8(+) T cells in a type I IFN-dependent fashion. This enhanced cross-priming is accompanied by a higher density of OVA(256-264)/H-2K(b) complexes on CD8α(+) DCs treated with polyU, as well as by upregulation of costimulatory molecules and increased secretion of proinflammatory cytokines by DCs. Cross-priming of CD8(+) T cells by DCs treated with polyU requires proteasome and Ag translocation to cytosol through the Sec61 channel in DCs. The observed enhancement in OVA cross-presentation with polyU in DCs could be mediated by a limited Ag degradation in endophagosomal compartments and a higher permanence of OVA peptide/MHC class I complexes on DCs. These observations clearly reveal that key steps of Ag processing for cross-presentation can be modulated by TLR ligands, opening new avenues for understanding their mechanisms as adjuvants of the immune response.
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Affiliation(s)
- María I Crespo
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
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Liechtenstein T, Dufait I, Lanna A, Breckpot K, Escors D. MODULATING CO-STIMULATION DURING ANTIGEN PRESENTATION TO ENHANCE CANCER IMMUNOTHERAPY. IMMUNOLOGY, ENDOCRINE & METABOLIC AGENTS IN MEDICINAL CHEMISTRY 2012; 12:224-235. [PMID: 22945252 PMCID: PMC3428911 DOI: 10.2174/187152212802001875] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
One of the key roles of the immune system is the identification of potentially dangerous pathogens or tumour cells, and raising a wide range of mechanisms to eliminate them from the organism. One of these mechanisms is activation and expansion of antigen-specific cytotoxic T cells, after recognition of antigenic peptides on the surface of antigen presenting cells such as dendritic cells (DCs). However, DCs also process and present autoantigens. Therefore, antigen presentation has to occur in the appropriate context to either trigger immune responses or establishing immunological tolerance. This is achieved by co-stimulation of T cells during antigen presentation. Co-stimulation consists on the simultaneous binding of ligand-receptor molecules at the immunological synapse which will determine the type and extent of T cell responses. In addition, the type of cytokines/chemokines present during antigen presentation will influence the polarisation of T cell responses, whether they lead to tolerance, antibody responses or cytotoxicity. In this review, we will focus on approaches manipulating co-stimulation during antigen presentation, and the role of cytokine stimulation on effective T cell responses. More specifically, we will address the experimental strategies to interfere with negative co-stimulation such as that mediated by PD-L1 (Programmed cell death 1 ligand 1)/PD-1 (Programmed death 1) to enhance anti-tumour immunity.
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Affiliation(s)
- Therese Liechtenstein
- Division of Infection and Immunity. Rayne Institute. University College London. 5 University Street. WC1E 6JF. London. United Kingdom
| | - Ines Dufait
- Division of Infection and Immunity. Rayne Institute. University College London. 5 University Street. WC1E 6JF. London. United Kingdom
- Department of Physiology-Immunology. Medical School. Free University of Brussels. Laarbeeklaan 103. 1090 Jette. Belgium
| | - Alessio Lanna
- Division of Infection and Immunity. Rayne Institute. University College London. 5 University Street. WC1E 6JF. London. United Kingdom
| | - Karine Breckpot
- Department of Physiology-Immunology. Medical School. Free University of Brussels. Laarbeeklaan 103. 1090 Jette. Belgium
| | - David Escors
- Division of Infection and Immunity. Rayne Institute. University College London. 5 University Street. WC1E 6JF. London. United Kingdom
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28
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Sarvestani ST, Williams BRG, Gantier MP. Human Toll-like receptor 8 can be cool too: implications for foreign RNA sensing. J Interferon Cytokine Res 2012; 32:350-61. [PMID: 22817608 DOI: 10.1089/jir.2012.0014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Recent advances in our understanding of foreign nucleic acid sensing indicate an important role for the human Toll-like receptor (TLR) 8 in the initiation of immune responses to certain pathogens. However, TLR8, far too often grouped together with TLR7 for its common ability to detect RNA, has a function on its own in the initiation of specific proinflammatory responses to viruses and bacteria. Here, we present an overview of what is currently known of human TLR8 biology, from genetic regulation to its function in innate immunity, and discuss how TLR8 could present novel therapeutic opportunities in viral and cancer diseases.
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Affiliation(s)
- Soroush T Sarvestani
- Centre for Cancer Research, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
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29
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Sainathan SK, Bishnupuri KS, Aden K, Luo Q, Houchen CW, Anant S, Dieckgraefe BK. Toll-like receptor-7 ligand Imiquimod induces type I interferon and antimicrobial peptides to ameliorate dextran sodium sulfate-induced acute colitis. Inflamm Bowel Dis 2012; 18:955-67. [PMID: 21953855 PMCID: PMC3878618 DOI: 10.1002/ibd.21867] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 07/26/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND The pathogenesis of inflammatory bowel disease (IBD) is associated with a dysregulated mucosal immune response. Certain stimulators of innate immunity (CpG DNA or GM-CSF) are reported to be anti-inflammatory in IBD. Toll-like receptor-7 (TLR7) is an important regulator of innate immunity and its activation plays a key role in induction of type I interferon (IFN). The present study tests the hypothesis that the TLR7 agonists Imiquimod has therapeutic efficacy in IBD. METHODS Acute colitis was induced in Balb/c mice by giving 5% dextran sodium sulfate (DSS) in drinking water for 7 days. Mice were treated with Imiquimod either orally or topically and its therapeutic effects on disease activity were examined. Isolated mouse CD11c+ dendritic cells and human intestinal epithelial cells (HT29, HCT116) were treated with Imiquimod (10 μg/mL) and their susceptibility to intracellular Salmonella typhimurium infection was assessed by gentamicin protection assay. RESULTS Oral administration of Imiquimod induced type I IFN expression in the gastrointestinal mucosa and ameliorated DSS-induced acute colitis as assessed by clinical parameters, histology, and mRNA expression of proinflammatory cytokines. Topical administration of Imiquimod also ameliorated DSS colitis by inducing the expression of type I IFN in the colonic mucosa. However, no evidence for a systemic IFN response was observed. Imiquimod treatments to both CD11c+ and intestinal epithelial cells significantly increased expression of antimicrobial peptides (AMPs) and reduced survival of intracellular S. typhimurium. CONCLUSIONS Imiquimod induces type I IFN and AMP to ameliorate DSS-induced acute colitis and prevents Salmonella survival. Therefore, Imiquimod treatments provide a new therapeutic approach for IBD patients.
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Affiliation(s)
- Satheesh K. Sainathan
- Division of Gastroenterology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kumar S. Bishnupuri
- Division of Gastroenterology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Konrad Aden
- Institute of Clinical Molecular Biology, Christian-Albrechts-University Kiel, Germany
| | - Qizhi Luo
- Division of Gastroenterology, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | - Shrikant Anant
- Kansas University, School of Medicine, Kansas city, Kansas, USA
| | - Brian K. Dieckgraefe
- Division of Gastroenterology, Washington University School of Medicine, St. Louis, Missouri, USA
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Lumsden JM, Nurmukhambetova S, Klein JH, Sattabongkot J, Bennett JW, Bertholet S, Fox CB, Reed SG, Ockenhouse CF, Howard RF, Polhemus ME, Yadava A. Evaluation of immune responses to a Plasmodium vivax CSP-based recombinant protein vaccine candidate in combination with second-generation adjuvants in mice. Vaccine 2012; 30:3311-9. [PMID: 22425788 DOI: 10.1016/j.vaccine.2012.03.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 02/01/2012] [Accepted: 03/01/2012] [Indexed: 12/12/2022]
Abstract
Plasmodium vivax is the major cause of malaria outside of sub-Saharan Africa and causes morbidity and results in significant economic impact in developing countries. In order to produce a P. vivax vaccine for global use, we have previously reported the development of VMP001, based on the circumsporozoite protein (CSP) of P. vivax. Our interest is to evaluate second-generation vaccine formulations to identify novel combinations of adjuvants capable of inducing strong, long-lasting immune responses. In this study, groups of C57BL/6J mice were immunized subcutaneously three times with VMP001 emulsified with synthetic TLR4 (GLA) or TLR7/8 (R848) agonist in stable emulsion (SE), a combination of the TLR4 and TLR7/8 agonists, or SE alone. Sera and splenocytes were tested for the presence of antigen-specific humoral and cellular responses, respectively. All groups of mice generated high titers of anti-P. vivax IgG antibodies as detected by ELISA and immunofluorescence assay. GLA-SE promoted a shift in the antibody response to a Th1 profile, as demonstrated by the change in IgG2c/IgG1 ratio. In addition, GLA-SE induced a strong cellular immune response characterized by multi-functional, antigen-specific CD4(+) T cells secreting IL-2, TNF and IFN-γ. In contrast, mice immunized with SE or R848-SE produced low numbers of antigen-specific CD4(+) T cells, and these T cells secreted IL-2 and TNF, but not IFN-γ. Finally, R848-SE did not enhance the immune response compared to GLA-SE alone. Based on these results, we conclude that the combination of VMP001 and GLA-SE is highly immunogenic in mice and may serve as a potential second-generation vaccine candidate against vivax malaria.
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Affiliation(s)
- Joanne M Lumsden
- Malaria Vaccine Branch United States, Military Malaria Research Program, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
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31
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Direct activation of antigen-presenting cells is required for CD8+ T-cell priming and tumor vaccination. Proc Natl Acad Sci U S A 2011; 108:17414-9. [PMID: 21987815 DOI: 10.1073/pnas.1108945108] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Successful priming of adaptive immune responses is crucially dependent on innate activation signals that convert resting antigen-presenting cells (APCs) into immunogenic ones. APCs expressing the relevant innate pattern recognition receptors can be directly activated by pathogen-associated molecular patterns (PAMPs) to become competent to prime T-cell responses. Alternatively, it has been suggested that APCs could be activated indirectly by proinflammatory mediators synthesized by PAMP-exposed cells. However, data obtained with CD4(+) T cells suggest that inflammatory signals often cannot substitute for direct pattern recognition in APC activation for the priming of T helper responses. To test whether the same is true for CD8(+) T cells, we studied cytotoxic T lymphocyte development in vitro and in mixed chimeric mice in which coexisting APCs can either present a preprocessed model antigen or directly recognize a given PAMP, but not both. We show that indirectly activated APCs promote antigen-specific proliferation of naïve CD8(+) T cells but fail to support their survival and cytotoxic T lymphocyte differentiation. Furthermore, CD8(+) T cells primed by indirectly activated APCs are unable to reject tumors. Thus, inflammation cannot substitute for direct recognition of single PAMPs in CD8(+) T-cell priming. These findings have important practical implications for vaccine design, indicating that adjuvants must be judiciously chosen to trigger the relevant pattern recognition receptors in APCs.
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TLR7 enables cross-presentation by multiple dendritic cell subsets through a type I IFN-dependent pathway. Blood 2011; 118:3028-38. [PMID: 21813451 DOI: 10.1182/blood-2011-04-348839] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Conjugation of TLR agonists to protein or peptide antigens has been demonstrated in many studies to be an effective vaccine formula in inducing cellular immunity. However, the molecular and cellular mediators involved in TLR-induced immune responses have not been carefully examined. In this study, we identify Type I IFN and IL-12 as critical mediators of cross-priming induced by a TLR7 agonist-antigen conjugate. We demonstrate that TLR7-driven cross-priming requires both Type I IFN and IL-12. Signaling through the IFN-αβR was required for the timely recruitment and accumulation of activated dendritic cells in the draining lymph nodes. Although IL-12 was indispensable during cross-priming, it did not regulate DC function. Therefore, the codependency for these 2 cytokines during TLR7-induced cross-priming is the result of their divergent effects on different cell-types. Furthermore, although dermal and CD8α(+) DCs were able to cross-prime CD8(+) T cells, Langerhans cells were unexpectedly found to potently cross-present antigen and support CD8(+) T-cell expansion, both in vitro and in vivo. Collectively, the data show that a TLR7 agonist-antigen conjugate elicits CD8(+) T-cell responses by the coordinated recruitment and activation of both tissue-derived and lymphoid organ-resident DC subsets through a Type I IFN and IL-12 codependent mechanism.
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Kastenmüller K, Wille-Reece U, Lindsay RWB, Trager LR, Darrah PA, Flynn BJ, Becker MR, Udey MC, Clausen BE, Igyarto BZ, Kaplan DH, Kastenmüller W, Germain RN, Seder RA. Protective T cell immunity in mice following protein-TLR7/8 agonist-conjugate immunization requires aggregation, type I IFN, and multiple DC subsets. J Clin Invest 2011; 121:1782-96. [PMID: 21540549 DOI: 10.1172/jci45416] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 02/16/2011] [Indexed: 01/08/2023] Open
Abstract
The success of a non-live vaccine requires improved formulation and adjuvant selection to generate robust T cell immunity following immunization. Here, using protein linked to a TLR7/8 agonist (conjugate vaccine), we investigated the functional properties of vaccine formulation, the cytokines, and the DC subsets required to induce protective multifunctional T cell immunity in vivo. The conjugate vaccine required aggregation of the protein to elicit potent Th1 CD4+ and CD8+ T cell responses. Remarkably, the conjugate vaccine, through aggregation of the protein and activation of TLR7 in vivo, led to an influx of migratory DCs to the LN and increased antigen uptake by several resident and migratory DC subsets, with the latter effect strongly influenced by vaccine-induced type I IFN. Ex vivo migratory CD8-DEC205+CD103-CD326- langerin-negative dermal DCs were as potent in cross-presenting antigen to naive CD8+ T cells as CD11c+CD8+ DCs. Moreover, these cells also influenced Th1 CD4+ T cell priming. In summary, we propose a model in which broad-based T cell-mediated responses upon vaccination can be maximized by codelivery of aggregated protein and TLR7/8 agonist, which together promote optimal antigen acquisition and presentation by multiple DC subsets in the context of critical proinflammatory cytokines.
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Affiliation(s)
- Kathrin Kastenmüller
- Vaccine Research Center and Cellular Immunology Section, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
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Velasquez LS, Hjelm BE, Arntzen CJ, Herbst-Kralovetz MM. An intranasally delivered Toll-like receptor 7 agonist elicits robust systemic and mucosal responses to Norwalk virus-like particles. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 17:1850-8. [PMID: 20962211 PMCID: PMC3008198 DOI: 10.1128/cvi.00230-10] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 08/18/2010] [Accepted: 10/09/2010] [Indexed: 01/01/2023]
Abstract
Norwalk virus (NV) is an enteric pathogen from the genus Norovirus and a major cause of nonbacterial gastroenteritis in humans. NV virus-like particles (VLPs) are known to elicit systemic and mucosal immune responses when delivered nasally; however, the correlates of immune protection are unknown, and codelivery with a safe and immunogenic mucosal adjuvant may enhance protective anti-NV immune responses. Resiquimod (R848), an imidazoquinoline-based Toll-like receptor 7 and/or 8 (TLR7/8) agonist, is being evaluated as an adjuvant in FDA-approved clinical vaccine trials. As such, we evaluated the adjuvant activity of two imidazoquinoline-based TLR7 and TLR7/8 agonists when codelivered intranasally with plant-derived NV VLPs. We also compared the activity of these agonists to the gold standard mucosal adjuvant, cholera toxin (CT). Our results indicate that codelivery with the TLR7 agonist, gardiquimod (GARD), induces NV VLP-specific serum IgG and IgG isotype responses and mucosal IgA responses in the gastrointestinal, respiratory, and reproductive tracts that are superior to those induced by R848 and comparable to those induced by the mucosal adjuvant CT. This study supports the continued investigation of GARD as a mucosal adjuvant for NV VLPs and possible use for other VLP-based vaccines for which immune responses at distal mucosal sites (e.g., respiratory and reproductive tracts) are desired.
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Affiliation(s)
- Lissette S. Velasquez
- Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, Arizona, School of Life Sciences, Arizona State University, Tempe, Arizona, Translational Genomics Research Institute, Phoenix, Arizona, Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
| | - Brooke E. Hjelm
- Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, Arizona, School of Life Sciences, Arizona State University, Tempe, Arizona, Translational Genomics Research Institute, Phoenix, Arizona, Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
| | - Charles J. Arntzen
- Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, Arizona, School of Life Sciences, Arizona State University, Tempe, Arizona, Translational Genomics Research Institute, Phoenix, Arizona, Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
| | - Melissa M. Herbst-Kralovetz
- Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, Arizona, School of Life Sciences, Arizona State University, Tempe, Arizona, Translational Genomics Research Institute, Phoenix, Arizona, Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
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36
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Ng SC, Kamm MA, Stagg AJ, Knight SC. Intestinal dendritic cells: their role in bacterial recognition, lymphocyte homing, and intestinal inflammation. Inflamm Bowel Dis 2010; 16:1787-807. [PMID: 20222140 DOI: 10.1002/ibd.21247] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dendritic cells (DCs) play a key role in discriminating between commensal microorganisms and potentially harmful pathogens and in maintaining the balance between tolerance and active immunity. The regulatory role of DC is of particular importance in the gut where the immune system lies in intimate contact with the highly antigenic external environment. Intestinal DC constantly survey the luminal microenvironment. They act as sentinels, acquiring antigens in peripheral tissues before migrating to secondary lymphoid organs to activate naive T cells. They are also sensors, responding to a spectrum of environmental cues by extensive differentiation or maturation. Recent studies have begun to elucidate mechanisms for functional specializations of DC in the intestine that may include the involvement of retinoic acid and transforming growth factor-β. Specialized CD103(+) intestinal DC can promote the differentiation of Foxp3(+) regulatory T cells via a retinoic acid-dependent process. Different DC outcomes are, in part, influenced by their exposure to microbial stimuli. Evidence is also emerging of the close interaction between bacteria, epithelial cells, and DC in the maintenance of intestinal immune homeostasis. Here we review recent advances of functionally specialized intestinal DC and their mechanisms of antigen uptake and recognition. We also discuss the interaction of DC with intestinal microbiota and their ability to orchestrate protective immunity and immune tolerance in the host. Lastly, we describe how DC functions are altered in intestinal inflammation and their emerging potential as a therapeutic target in inflammatory bowel disease.
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Affiliation(s)
- S C Ng
- Antigen Presentation Research Group, Faculty of Medicine, Imperial College London, Northwick Park and St Mark's Campus, Harrow, UK
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37
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Sabarth N, Chamberlain L, Brett S, Tite J, Craigen J. Induction of homologous rather than heterologous antigen-specific CD4 T cell responses is critical for functional CD8 T cell responses in mice transgenic for a foreign antigen. THE JOURNAL OF IMMUNOLOGY 2010; 185:4590-601. [PMID: 20861346 DOI: 10.4049/jimmunol.0803994] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The development of a successful cancer vaccine requires the ability to break immunological tolerance to self-Ags expressed on tumor cells. The transgenic rat insulin promoter (RIP) OVA(LOW) mouse model has been reported to be hyporesponsive for both OVA-specific CD4 and CD8 T cell responses. The experiments described in the current study show that this hyporesponsiveness can be overcome by inclusion of GM-CSF and the TLR7 agonist imiquimod as adjuvants in a DNA immunization regimen with OVA-encoding plasmids. High frequencies of OVA-specific CD8 and CD4 T cells, including a response to a CD4 T cell epitope seen only in the RIP OVA(LOW) mice, were generated by this regimen. These responses were associated with the development of autoimmunity and increased protection to tumor challenge in the RIP OVA(LOW) mice. Heterologous CD4 T cell help has been shown to improve functional CD8 T cell responses, and we confirmed that inclusion of the CD4 T cell epitope pan HLA-DR-binding epitope improved CD8 T cell responses compared with self-Ag alone. Addition of GM-CSF and imiquimod, however, resulted in dominance of the pan HLA-DR-binding epitope-specific response over the OVA-specific CD4 T cell responses, decreased OVA-specific CD8 T cell numbers and function in tolerant RIP OVA(LOW) mice, and failure to induce diabetes. The results of this study suggest that the use of heterologous help needs to be evaluated carefully in the context of specific immunization regimes and that a preferable approach may be adjuvantization of DNA vaccines.
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Affiliation(s)
- Nicolas Sabarth
- GlaxoSmithKline, Medical Research Centre, Biopharm Research and Development, Hertfordshire, United Kingdom
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38
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Oh JZ, Kedl RM. The capacity to induce cross-presentation dictates the success of a TLR7 agonist-conjugate vaccine for eliciting cellular immunity. THE JOURNAL OF IMMUNOLOGY 2010; 185:4602-8. [PMID: 20844205 DOI: 10.4049/jimmunol.1001892] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Covalent conjugation of TLR agonists to protein Ags often facilitates the generation of a CD8(+) T cell response. However, mechanisms underlying the efficacy of the conjugate over its unconjugated counterpart have been largely uninvestigated. In this study, we show that conjugation of a TLR7 agonist enhances CD8(+) T cell responses without affecting Ag persistence and with minimal impact on cellular uptake of the Ag in vivo. Instead, the conjugated form induced a robust accumulation of dendritic cells (DCs) in regional lymph nodes. Perhaps more importantly, cross-presentation in DCs was detected only when the Ag was delivered in the conjugated form with the TLR7 agonist. Collectively, these data represent the first demonstration that a TLR agonist-Ag conjugate elicits CD8(+) T cell responses based not on its capacity to induce DC maturation or Ag persistence and uptake, but on the engagement of DC cross-presentation pathways.
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Affiliation(s)
- Jason Z Oh
- Integrated Department of Immunology, University of Colorado, Denver, CO 80206, USA
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39
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Bachelder EM, Beaudette TT, Broaders KE, Fréchet JMJ, Albrecht MT, Mateczun AJ, Ainslie KM, Pesce JT, Keane-Myers AM. In vitro analysis of acetalated dextran microparticles as a potent delivery platform for vaccine adjuvants. Mol Pharm 2010; 7:826-35. [PMID: 20230025 DOI: 10.1021/mp900311x] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toll-like receptor (TLR) agonists induce potent innate immune responses and can be used in the development of novel vaccine adjuvants. However, access to TLRs can be challenging as exemplified by TLR 7, which is located intracellularly in endosomal compartments. To increase recognition and subsequent stimulatory effects of TLR 7, imiquimod was encapsulated in acetalated dextran (Ac-DEX) microparticles. Ac-DEX, a water-insoluble and biocompatible polymer, is relatively stable at pH 7.4, but degrades rapidly under acidic conditions, such as those found in lysosomal vesicles. To determine the immunostimulatory capacity of encapsulated imiquimod, we compared the efficacy of free versus encapsulated imiquimod in activating RAW 264.7 macrophages, MH-S macrophages, and bone marrow derived dendritic cells. Encapsulated imiquimod significantly increased IL-1 beta, IL-6, and TNF-alpha cytokine expression in macrophages relative to the free drug. Furthermore, significant increases were observed in classic macrophage activation markers (iNOS, PD1-L1, and NO) after treatment with encapsulated imiquimod over the free drug. Also, bone marrow derived dendritic cells produced significantly higher levels of IL-1 beta, IL-6, IL-12p70, and MIP-1 alpha as compared to their counterparts receiving free imiquimod. These results suggest that encapsulation of TLR ligands within Ac-DEX microparticles results in increased immunostimulation and potentially better protection from disease when used in conjunction with vaccine formulations.
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Affiliation(s)
- Eric M Bachelder
- Department of Chemistry, University of California, Berkeley, California 94720-1460, USA
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40
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Novak N, Koch S, Allam JP, Bieber T. Dendritic cells: bridging innate and adaptive immunity in atopic dermatitis. J Allergy Clin Immunol 2010; 125:50-9. [PMID: 20109736 DOI: 10.1016/j.jaci.2009.11.019] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 11/04/2009] [Accepted: 11/16/2009] [Indexed: 12/17/2022]
Abstract
Much knowledge has been gained about the multifaceted functions of dendritic cells (DCs). The central role of various DC subtypes as bridges between innate and adaptive immunity has become more and more evident. However, a high number of differences exist in the expression of pattern-recognition receptors, the first sensors of the innate immune system, in particular Toll-like receptors (TLRs) by distinct DC subtypes (including myeloid and plasmacytoid DCs), their maturation stage, and tissue distribution, as well as state of health or disease. Furthermore, a plethora of variations in human and murine model systems have to be considered. This review sheds some light on this complex and rapidly growing field. It summarizes the most recent findings and deals with the role of TLR-expressing DCs as promoters of chronic inflammatory immune responses in patients with atopic dermatitis, as well as tolerogenic pathways. Therefore TLR-bearing DCs represent promising targets, which might help to improve tolerance induction during immunotherapeutic approaches in the future.
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Affiliation(s)
- Natalija Novak
- Department of Dermatology and Allergy, University of Bonn, D-53105 Bonn, Germany
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Plasmacytoid dendritic cell-derived type I interferon is crucial for the adjuvant activity of Toll-like receptor 7 agonists. Blood 2010; 115:1949-57. [PMID: 20065291 DOI: 10.1182/blood-2009-08-238543] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
There is a high demand for the development of adjuvants that induce cytotoxic T lymphocytes, which are crucial for the elimination of intracellular pathogens and tumor cells. Toll-like receptor (TLR) agonists are prime candidates to fulfill this role because they induce innate immune activation and promote adaptive immune responses. The successful application of the TLR7 agonist R837 for treatment of basal cell carcinoma shows the potential for exploiting this pathway in tumor immunotherapy. Imidazoquinolines like R837 and stimulatory ssRNA oligonucleotides both trigger TLR7-mediated immune activation, but little is known about their comparative ability to promote immunity induction. We investigated differences in innate immune activation and adjuvant activity between the imidazoquinoline R848 and the ssRNA TLR7 agonist polyUs21. In contrast to R848, polyUs21 induced detectable levels of intracellular interferon-alpha (IFN-alpha) in plasmacytoid dendritic cells (PDCs). In immunization studies, only polyUs21 led to robust priming of type 1 T helper cells and cytotoxic T lymphocytes, and it was more efficient in inducing antitumor immunity than R848. Notably, exogenous IFN-alpha augmented the adjuvant activity of R848, whereas depletion of PDC abrogated the adjuvanticity of polyUs21. This study, therefore, identifies sufficient IFN-alpha production by PDC as an important determinant of vaccine efficacy.
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42
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Phillipps KSM, Wykes MN, Liu XQ, Brown M, Blanchfield J, Toth I. A novel synthetic adjuvant enhances dendritic cell function. Immunology 2009; 128:e582-8. [PMID: 19740319 PMCID: PMC2753928 DOI: 10.1111/j.1365-2567.2008.03038.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2008] [Revised: 11/15/2008] [Accepted: 12/04/2008] [Indexed: 01/08/2023] Open
Abstract
The lipid core peptide (LCP) is a novel, synthetic, self-adjuvanted vaccine delivery system that neatly incorporates the adjuvant, carrier and antigenic peptides of a vaccine into a single molecular entity. This system has been previously shown to efficiently deliver vaccines and induce immunity. Because adjuvants target sentinels of the immune response, such as dendritic cells (DCs), that are widely distributed throughout the body to initiate specific immune responses, we investigated the effects of the adjuvant on DCs. Here we show that LCP targets vaccines to DCs and induces their activation.
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Affiliation(s)
- Karen S M Phillipps
- School of Molecular and Microbial Sciences (SMMS), The University of Queensland, St Lucia, Queensland, Australia
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43
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Joffre O, Nolte MA, Spörri R, Reis e Sousa C. Inflammatory signals in dendritic cell activation and the induction of adaptive immunity. Immunol Rev 2009; 227:234-47. [PMID: 19120488 DOI: 10.1111/j.1600-065x.2008.00718.x] [Citation(s) in RCA: 418] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Pathogen invasion induces a rapid inflammatory response initiated through the recognition of pathogen-derived molecules by pattern recognition receptors (PRRs) expressed on both immune and non-immune cells. The initial wave of pro-inflammatory cytokines and chemokines limits pathogen spread and recruits and activates immune cells to eradicate the invaders. Dendritic cells (DCs) are responsible for initiating a subsequent phase of immunity, dominated by the action of pathogen-specific T and B cells. As for the early pro-inflammatory response, DC activation is triggered by PRR signals. These signals convert resting DCs into potent antigen-presenting cells capable of promoting the expansion and effector differentiation of naive pathogen-specific T cells. However, it has been argued that signals from PRRs are not a prerequisite for DC activation and that pro-inflammatory cytokines have the same effect. Although this may appear like an efficient way to expand the number of DCs that initiate adaptive immunity, evidence is accumulating that DCs activated indirectly by inflammatory cytokines are unable to induce functional T-cell responses. Here, we review the differences between PRR-triggered and cytokine-induced DC activation and speculate on a potential role for DCs activated by inflammatory signals in tolerance induction rather than immunity.
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Affiliation(s)
- Olivier Joffre
- Immunobiology Laboratory, Cancer Research UK, London Research Institute, Lincoln's Inn Fields Laboratories, London, UK
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44
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Wong KL, Tang LFM, Lew FC, Wong HSK, Chua YL, MacAry PA, Kemeny DM. CD44high memory CD8 T cells synergize with CpG DNA to activate dendritic cell IL-12p70 production. THE JOURNAL OF IMMUNOLOGY 2009; 183:41-50. [PMID: 19535645 DOI: 10.4049/jimmunol.0803473] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Protective memory CD8 T cell responses are generally associated with the rapid and efficient acquisition of CTL function. However, the ability of memory CD8 T cells to modulate immune responses through interactions with dendritic cells (DCs) during the early states of secondary Ag exposure is poorly understood. In this study, we show that murine Ag-specific CD44(high) CD8 T cells, representing CD8 T cells of the memory phenotype, potently activate DCs to produce high levels of IL-12p70 in conjunction with stimulation of DCs with the TLR 9 ligand, unmethylated CpG DNA. IL-12p70 production was produced predominantly by CD8alpha(+) DCs and plasmacytoid DCs, and mediated by CD8 T cell-derived cytokines IFN-gamma, GM-CSF, TNF-alpha, and surface CD40L. We also find that CD44(high) memory phenotype CD8 T cells were better DC IL-12p70 stimulators than CD44(low) naive phenotype CD8 T cells, and this was attributed to higher levels of IFN-gamma and GM-CSF produced by CD44(high) memory phenotype CD8 T cells during their Ag specific interaction with DCs. Our study identifies CpG DNA as the most effective TLR ligand that cooperates with CD8 T cells for DC IL-12p70 production, and suggests that effectiveness of memory CD8 T cells could be attributed to their ability to rapidly and effectively induce protective Th1 immunity during early stages of pathogen reinfection.
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Affiliation(s)
- Kok Loon Wong
- Department of Microbiology, Centre for Life Sciences, National University of Singapore, Singapore
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45
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Sun B, Robertsen B, Wang Z, Liu B. Identification of an Atlantic salmon IFN multigene cluster encoding three IFN subtypes with very different expression properties. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2009; 33:547-58. [PMID: 19007809 DOI: 10.1016/j.dci.2008.10.001] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 09/29/2008] [Accepted: 10/01/2008] [Indexed: 05/27/2023]
Abstract
A cluster of 11 interferon (IFN) genes were identified in the Atlantic salmon genome linked to the growth hormone 1 gene. The genes encode three different IFN subtypes; IFNa (two genes), IFNb (four genes) and IFNc (five genes), which show 22-32% amino acid sequence identity. Expression of the fish IFNs were studied in head kidney, leukocytes or TO cells after stimulation with the dsRNA poly I:C or the imidazoquinoline S-27609. In mammals, poly I:C induces IFN-beta through the RIG-I/MDA5 or the TLR3 pathway, both of which are dependent on NF-kB. In contrast, S-27609 induces mammalian IFN-alpha in plasmacytoid dendritic cells through the TLR7 pathway independent of NF-kappaB. The presence of an NF-kappaB site in their promoters and their strong up-regulation by poly I:C, suggest that salmon IFNa1/IFNa2 are induced through similar pathways as IFN-beta. In contrast, the apparent lack of NF-kappaB motif in the promoter and the strong upregulation by S-27609 in head kidney and leukocytes, suggest that IFNb genes are induced through a pathway similar to mammalian IFN-alpha. IFNc genes showed expression patterns different from both IFNa and IFNb. Taken together, salmon IFNa and IFNb are not orthologs of mammalian IFN-beta and IFN-alpha, respectively, but appear to utilize similar induction pathways.
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Affiliation(s)
- Baojian Sun
- Department of Marine Biotechnology, Norwegian College of Fishery Science, University of Tromsø, N-9037 Tromsø, Norway
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46
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Salem ML, Díaz-Montero CM, Al-Khami AA, El-Naggar SA, Naga O, Montero AJ, Khafagy A, Cole DJ. Recovery from cyclophosphamide-induced lymphopenia results in expansion of immature dendritic cells which can mediate enhanced prime-boost vaccination antitumor responses in vivo when stimulated with the TLR3 agonist poly(I:C). JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2009; 182:2030-40. [PMID: 19201856 PMCID: PMC3066095 DOI: 10.4049/jimmunol.0801829] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent preclinical studies suggest that vaccination following adoptive transfer of CD8(+) T cells into a lymphopenic host can augment the therapeutic antitumor responses of the transferred cells. However, the mechanism by which the lymphopenic microenvironment benefits Ag-specific CD8(+) T cell responses remains elusive. We show herein that induction of lymphodepletion by a single 4 mg cyclophosphamide (CTX) treatment induces a marked expansion of immature dendritic cells (DCs) in the peripheral blood on days 8-16 post-CTX (termed restoration phase). In vitro, these DCs were functional, because they showed normal phagocytosis and effective Ag presentation capability upon activation. In vivo, administration of the TLR3 agonist poly(I:C) at the peak of DC expansion (day 12 postlymphopenia) induced inflammatory cytokine production and increases in the number of activated DCs in lymph nodes. Importantly, boosting with gp100(25-33) melanoma peptide combined with poly(I:C) 12 days after an initial priming with the same regimen significantly increased the expansion and the antitumor efficacy of adoptively transferred pmel-1 CD8(+) T cells. These responses were abrogated after depletion of activated DCs during Ag boosting. In conclusion, our data show that CTX treatment induces, during the restoration phase, expansion of immature DCs, which are functional and can be exploited in vivo to foster more effective antitumor adoptive immunotherapy strategies.
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Affiliation(s)
- Mohamed L Salem
- Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425, USA.
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47
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Wong KL, Lew FC, MacAry PA, Kemeny DM. CD40L-expressing CD8 T cells prime CD8alpha(+) DC for IL-12p70 production. Eur J Immunol 2008; 38:2251-62. [PMID: 18600823 DOI: 10.1002/eji.200838199] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
CD8alpha(+) DC are implicated as the principle DC subset for cross-presentation and cross-priming of cytotoxic CD8 T cell responses. In this study, we demonstrate another unique facet of the CD8alpha(+) DC and CD8 T cell relationship, by showing that CD8 T cells reciprocally activate CD8alpha(+) DC, but not CD8alpha(-) DC, for IL-12p70 production, the key Th1-promoting cytokine. This effect was observed during an antigen-specific interaction between DC and activated CD8 T cells, along with secondary TLR stimulation of DC by LPS. Activated CD8 T cells use a combination of IFN-gamma and CD40L, which is rapidly up-regulated post-stimulation, to prime DC for IL-12p70 production during an antigen-specific response. Our results suggest that the interaction between CD8alpha(+) DC and antigen-primed CD8 T cells may form an important component of Th1-mediated immunity through the induction of IL-12p70.
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Affiliation(s)
- Kok Loon Wong
- Immunology Program and Department of Microbiology, Centre for Life Sciences, National University of Singapore, Singapore
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48
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Munakata K, Yamamoto M, Anjiki N, Nishiyama M, Imamura S, Iizuka S, Takashima K, Ishige A, Hioki K, Ohnishi Y, Watanabe K. Importance of the interferon-alpha system in murine large intestine indicated by microarray analysis of commensal bacteria-induced immunological changes. BMC Genomics 2008; 9:192. [PMID: 18439305 PMCID: PMC2408602 DOI: 10.1186/1471-2164-9-192] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 04/26/2008] [Indexed: 12/23/2022] Open
Abstract
Background Although microbiota play a critical role in the normal development and function of host immune systems, the underlying mechanisms, especially those involved in the large intestine (LI), remain unknown. In the present study, we performed transcriptome analysis of the LI of germ-free (GF) and specific pathogen-free (SPF) mice of the IQI strain, an inbred strain established from ICR mice. Results GeneChip analysis, quantitative real-time RT-PCR, and reconfirmation using bacteria-inoculated GF mice revealed differences in the expression levels of several immune-related genes, such as cryptdin-related sequences (CRS), certain subsets of type 1 interferon (IFN)-related genes, class Ib MHC molecules, and certain complements. LI expressed no authentic cryptdins but predominantly expressed CRS2, 4, and 7. The mRNA levels of IFN-related genes, including Irf7, Isgf3g, Ifit1 and Stat1, were lower in SPF- and flora-reconstituted mice. When an oral IFN-α inducer tilorone analog, R11567DA, was administered to SPF mice, IFN-α was induced rapidly in the LI at 4 h, whereas no IFN-α protein was detected in the small intestine (SI) or blood. In situ hybridization and immunohistochemistry suggested that the IFN-α production originated from Paneth cells in the SI, and portions of lamina proprial CD11b- or mPDCA1-positive cells in the LI. Conclusion The present study suggests that microbial colonization, while inducing the expression of anti-microbial peptides, results in the down-regulation of certain genes responsible for immune responses, especially for type I IFN synthesis. This may reflect the adaptation process of the immune system in the LI to prevent excessive inflammation with respect to continuous microbial exposure. Further, the repertoire of anti-microbial peptides and the extraordinary role of interferon producing cells in the LI have been found to be distinct from those in the SI.
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Affiliation(s)
- Kaori Munakata
- Center for Kampo Medicine, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582, Japan.
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Tomai MA, Miller RL, Lipson KE, Kieper WC, Zarraga IE, Vasilakos JP. Resiquimod and other immune response modifiers as vaccine adjuvants. Expert Rev Vaccines 2007; 6:835-47. [PMID: 17931162 DOI: 10.1586/14760584.6.5.835] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Synthetic immune response modifiers, such as resiquimod, are Toll-like receptor 7 and 8 agonists that act as vaccine adjuvants, enhancing antigen-specific antibody production and skewing immunity towards a Th1 response. These compounds stimulate dendritic cells to secrete cytokines, upregulate costimulatory molecule expression and enhance antigen presentation to T cells. The compounds have demonstrated vaccine adjuvant properties in a number of animal models. The adjuvant effects can be enhanced by measures that allow the drug to stay localized with the vaccine without quickly entering the systemic circulation. Clinical studies demonstrate that topical application of resiquimod and analogs is safe and effective at activating the local immune response. For injection, resiquimod or a similar compound may need to be formulated to allow for local immune activation without induction of systemic cytokines.
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Affiliation(s)
- Mark A Tomai
- 3M Drug Delivery Systems, 3M Center, 275-3E-10 St Paul, MN 55144, USA.
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50
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Fajardo-Moser M, Berzel S, Moll H. Mechanisms of dendritic cell-based vaccination against infection. Int J Med Microbiol 2007; 298:11-20. [PMID: 17719274 DOI: 10.1016/j.ijmm.2007.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Due to their unique capacity to initiate and regulate adaptive immune responses, dendritic cells (DC) represent the most potent antigen-presenting cells of the immune system. Immature DC reside in peripheral tissues, where they sample and process antigens and efficiently sense a large variety of signals from the surrounding environment. Toll-like receptors (TLR) expressed by DC play a critical role in the detection of invading pathogens as well as in triggering the subsequent immune responses. The differential expression of TLR by different DC subsets may correlate with the induction of different patterns of adaptive immune responses. The rapidly expanding and fundamental knowledge of DC biology furthers promising perspectives for the development of vaccination strategies in different fields. For example, the immunotherapeutic potential of antigen-pulsed DC for the treatment of cancer has been confirmed in a number of experimental tumour models. Furthermore, DC have been shown to serve as natural adjuvants in different models of infectious diseases, mediating protection against various types of pathogens. Using murine leishmaniasis as an example, we have demonstrated that DC, once properly conditioned ex vivo, mediate complete and durable protection against infection. Critical parameters determining the efficiency of DC-based vaccination against microbial pathogens include the origin of DC, the choice of antigen to be used for DC loading, the route of immunization and the state of DC maturation and activation. In the present review, we discuss the necessity to define the mechanisms responsible for the immunostimulatory capacity of DC in vivo, in order to exploit their full potential as vaccination tools.
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Affiliation(s)
- Marcela Fajardo-Moser
- Institut für Molekulare Infektionsbiologie, Universität Würzburg, Röntgenring 11, D-97070 Würzburg, Germany.
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