1
|
Wijesundara DK, Yeow A, McMillan CL, Choo JJ, Todorovic A, Mekonnen ZA, Masavuli MG, Young PR, Gowans EJ, Grubor-Bauk B, Muller DA. Superior efficacy of a skin-applied microprojection device for delivering a novel Zika DNA vaccine. Mol Ther Nucleic Acids 2023; 34:102056. [PMID: 38028199 PMCID: PMC10630652 DOI: 10.1016/j.omtn.2023.102056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023]
Abstract
Zika virus (ZIKV) infections are spreading silently with limited global surveillance in at least 89 countries and territories. There is a pressing need to develop an effective vaccine suitable for equitable distribution globally. Consequently, we previously developed a proprietary DNA vaccine encoding secreted non-structural protein 1 of ZIKV (pVAX-tpaNS1) to elicit rapid protection in a T cell-dependent manner in mice. In the current study, we evaluated the stability, efficacy, and immunogenicity of delivering this DNA vaccine into the skin using a clinically effective and proprietary high-density microarray patch (HD-MAP). Dry-coating of pVAX-tpaNS1 on the HD-MAP device resulted in no loss of vaccine stability at 40°C storage over the course of 28 days. Vaccination of mice (BALB/c) with the HD-MAP-coated pVAX-tpaNS1 elicited a robust anti-NS1 IgG response in both the cervicovaginal mucosa and systemically and afforded protection against live ZIKV challenge. Furthermore, the vaccination elicited a significantly higher magnitude and broader NS1-specific T helper and cytotoxic T cell response in vivo compared with traditional needle and syringe intradermal vaccination. Overall, the study highlights distinctive immunological advantages coupled with an excellent thermostability profile of using the HD-MAP device to deliver a novel ZIKV DNA vaccine.
Collapse
Affiliation(s)
- Danushka K. Wijesundara
- Vaxxas Biomedical Facility, Hamilton, QLD 4007, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Arthur Yeow
- Discipline of Surgery, The University of Adelaide, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - Christopher L.D. McMillan
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Jovin J.Y. Choo
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Aleksandra Todorovic
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Zelalem A. Mekonnen
- Discipline of Surgery, The University of Adelaide, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - Makutiro G. Masavuli
- Discipline of Surgery, The University of Adelaide, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - Paul R. Young
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Eric J. Gowans
- Discipline of Surgery, The University of Adelaide, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - Branka Grubor-Bauk
- Discipline of Surgery, The University of Adelaide, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - David A. Muller
- Vaxxas Biomedical Facility, Hamilton, QLD 4007, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
2
|
Garcia-Valtanen P, Hope CM, Masavuli MG, Yeow AEL, Balachandran H, Mekonnen ZA, Al-Delfi Z, Abayasingam A, Agapiou D, Stella AO, Aggarwal A, Bouras G, Gummow J, Ferguson C, O'Connor S, McCartney EM, Lynn DJ, Maddern G, Gowans EJ, Reddi BAJ, Shaw D, Kok-Lim C, Beard MR, Weiskopf D, Sette A, Turville SG, Bull RA, Barry SC, Grubor-Bauk B. SARS-CoV-2 Omicron variant escapes neutralizing antibodies and T cell responses more efficiently than other variants in mild COVID-19 convalescents. Cell Rep Med 2022; 3:100651. [PMID: 35654046 PMCID: PMC9110310 DOI: 10.1016/j.xcrm.2022.100651] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/24/2022] [Accepted: 05/11/2022] [Indexed: 12/12/2022]
Abstract
Coronavirus disease 2019 (COVID-19) convalescents living in regions with low vaccination rates rely on post-infection immunity for protection against re-infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We evaluate humoral and T cell immunity against five variants of concern (VOCs) in mild-COVID-19 convalescents at 12 months after infection with ancestral virus. In this cohort, ancestral, receptor-binding domain (RBD)-specific antibody and circulating memory B cell levels are conserved in most individuals, and yet serum neutralization against live B.1.1.529 (Omicron) is completely abrogated and significantly reduced for other VOCs. Likewise, ancestral SARS-CoV-2-specific memory T cell frequencies are maintained in >50% of convalescents, but the cytokine response in these cells to mutated spike epitopes corresponding to B.1.1.529 and B.1.351 (Beta) VOCs were impaired. These results indicate that increased antigen variability in VOCs impairs humoral and spike-specific T cell immunity post-infection, strongly suggesting that COVID-19 convalescents are vulnerable and at risk of re-infection with VOCs, thus stressing the importance of vaccination programs. Most mild COVID-19 convalescents maintain immunity at 12 months after disease onset B.1.1.529 escapes antibodies in convalescents infected with ancestral SARS-CoV-2 SARS-CoV-2 VOCs can partially avoid recognition by antigen-specific T cells Antigenic drift in SARS-CoV-2 VOCs significantly challenges convalescent immunity
Collapse
Affiliation(s)
- Pablo Garcia-Valtanen
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Christopher M Hope
- Molecular Immunology, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Women's and Children's Health Network, North Adelaide, SA, Australia
| | - Makutiro G Masavuli
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Arthur Eng Lip Yeow
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | | | - Zelalem A Mekonnen
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Zahraa Al-Delfi
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | | | - David Agapiou
- School of Medical Sciences, Faculty of Medicine, UNSW, Australia, Sydney, NSW, Australia
| | | | - Anupriya Aggarwal
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - George Bouras
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia; The Department of Surgery - Otolaryngology, Head and Neck Surgery, University of Adelaide and the Basil Hetzel Institute for Translational Health Research, Central Adelaide Local Health Network, Woodville South, SA, Australia
| | - Jason Gummow
- Gene Silencing and Expression Core Facility, Adelaide Health and Medical Sciences, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Catherine Ferguson
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - Stephanie O'Connor
- Intensive Care Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network and Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Erin M McCartney
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - David J Lynn
- Precision Medicine Theme, South Australian Health and Medical Research Institute, Adelaide, SA 5001, Australia; Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia
| | - Guy Maddern
- Discipline of Surgery, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Eric J Gowans
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Benjamin A J Reddi
- Intensive Care Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network and Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - David Shaw
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - Chuan Kok-Lim
- Gene Silencing and Expression Core Facility, Adelaide Health and Medical Sciences, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Microbiology and Infectious Diseases Department, SA Pathology, Adelaide, SA, Australia; Research Centre for Infectious Diseases, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Michael R Beard
- Research Centre for Infectious Diseases, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Daniela Weiskopf
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology (LJI), La Jolla, CA, USA
| | - Alessandro Sette
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology (LJI), La Jolla, CA, USA; Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego (UCSD), La Jolla, CA, USA
| | - Stuart G Turville
- The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Rowena A Bull
- School of Medical Sciences, Faculty of Medicine, UNSW, Australia, Sydney, NSW, Australia
| | - Simon C Barry
- Molecular Immunology, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Women's and Children's Health Network, North Adelaide, SA, Australia.
| | - Branka Grubor-Bauk
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia.
| |
Collapse
|
3
|
Ryan FJ, Hope CM, Masavuli MG, Lynn MA, Mekonnen ZA, Yeow AEL, Garcia-Valtanen P, Al-Delfi Z, Gummow J, Ferguson C, O'Connor S, Reddi BAJ, Hissaria P, Shaw D, Kok-Lim C, Gleadle JM, Beard MR, Barry SC, Grubor-Bauk B, Lynn DJ. Long-term perturbation of the peripheral immune system months after SARS-CoV-2 infection. BMC Med 2022; 20:26. [PMID: 35027067 PMCID: PMC8758383 DOI: 10.1186/s12916-021-02228-6] [Citation(s) in RCA: 123] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 12/29/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly infectious respiratory virus which is responsible for the coronavirus disease 2019 (COVID-19) pandemic. It is increasingly clear that recovered individuals, even those who had mild COVID-19, can suffer from persistent symptoms for many months after infection, a condition referred to as "long COVID", post-acute sequelae of COVID-19 (PASC), post-acute COVID-19 syndrome, or post COVID-19 condition. However, despite the plethora of research on COVID-19, relatively little is known about the molecular underpinnings of these long-term effects. METHODS We have undertaken an integrated analysis of immune responses in blood at a transcriptional, cellular, and serological level at 12, 16, and 24 weeks post-infection (wpi) in 69 patients recovering from mild, moderate, severe, or critical COVID-19 in comparison to healthy uninfected controls. Twenty-one of these patients were referred to a long COVID clinic and > 50% reported ongoing symptoms more than 6 months post-infection. RESULTS Anti-Spike and anti-RBD IgG responses were largely stable up to 24 wpi and correlated with disease severity. Deep immunophenotyping revealed significant differences in multiple innate (NK cells, LD neutrophils, CXCR3+ monocytes) and adaptive immune populations (T helper, T follicular helper, and regulatory T cells) in convalescent individuals compared to healthy controls, which were most strongly evident at 12 and 16 wpi. RNA sequencing revealed significant perturbations to gene expression in COVID-19 convalescents until at least 6 months post-infection. We also uncovered significant differences in the transcriptome at 24 wpi of convalescents who were referred to a long COVID clinic compared to those who were not. CONCLUSIONS Variation in the rate of recovery from infection at a cellular and transcriptional level may explain the persistence of symptoms associated with long COVID in some individuals.
Collapse
Affiliation(s)
- Feargal J Ryan
- Precision Medicine Theme, South Australian Health and Medical Research Institute, Adelaide, SA, 5001, Australia
| | - Christopher M Hope
- Women's and Children's Health Network, North Adelaide, SA, Australia.,Molecular Immunology, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Makutiro G Masavuli
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Miriam A Lynn
- Precision Medicine Theme, South Australian Health and Medical Research Institute, Adelaide, SA, 5001, Australia
| | - Zelalem A Mekonnen
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Arthur Eng Lip Yeow
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Pablo Garcia-Valtanen
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Zahraa Al-Delfi
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia
| | - Jason Gummow
- Gene Silencing and Expression Core Facility, Adelaide Health and Medical Sciences, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Catherine Ferguson
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - Stephanie O'Connor
- Intensive Care Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network and Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Benjamin A J Reddi
- Intensive Care Unit, Royal Adelaide Hospital, Central Adelaide Local Health Network and Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Pravin Hissaria
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - David Shaw
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia
| | - Chuan Kok-Lim
- Infectious Diseases Department, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia.,Microbiology and Infectious Diseases Department, SA Pathology, Adelaide, SA, Australia
| | - Jonathan M Gleadle
- Department of Renal Medicine, Flinders Medical Centre, Flinders University, Bedford Park, SA, 5042, Australia.,Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, 5042, Australia
| | - Michael R Beard
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Simon C Barry
- Women's and Children's Health Network, North Adelaide, SA, Australia. .,Molecular Immunology, Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.
| | - Branka Grubor-Bauk
- Viral Immunology Group, Adelaide Medical School, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA, Australia.
| | - David J Lynn
- Precision Medicine Theme, South Australian Health and Medical Research Institute, Adelaide, SA, 5001, Australia. .,Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, 5042, Australia.
| |
Collapse
|
4
|
Mekonnen ZA, Masavuli MG, Yu W, Gummow J, Whelan DM, Al-Delfi Z, Torresi J, Gowans EJ, Grubor-Bauk B. Enhanced T Cell Responses Induced by a Necrotic Dendritic Cell Vaccine, Expressing HCV NS3. Front Microbiol 2020; 11:559105. [PMID: 33343515 PMCID: PMC7739890 DOI: 10.3389/fmicb.2020.559105] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 10/28/2020] [Indexed: 12/21/2022] Open
Abstract
A vaccine that induces potent, broad and sustained cell-mediated immunity, resulting in effective memory has the potential to restrict hepatitis C (HCV) virus infection. Early, multi-functional CD4+ and CD8+ T cell responses against non-structural protein 3 (NS3) have been associated with HCV clearance. Necrotic cells generate strong immune responses and represent a major antigenic source used by dendritic cells (DC) for processing and presentation, but there is conflicting evidence as to their immunogenicity in vaccination. Immunization with DC loaded with viral antigens has been done in the past, but to date the immunogenicity of live vs. necrotic DC vaccines has not been investigated. We developed a DC2.4 cell line stably expressing HCV NS3, and compared the NS3-specific responses of live vs. necrotic NS3 DC. Vaccination of mice with necrotic NS3 DC increased the breadth of T-cell responses and enhanced the production of IL-2, TNF-α, and IFN-γ by effector memory CD4+ and CD8+T cells, compared to mice vaccinated with live NS3 DC. A single dose of necrotic NS3 DC vaccine induced a greater influx and activation of cross-presenting CD11c+ CD8α+ DC and necrosis-sensing Clec9A+ DC in the draining lymph nodes. Furthermore, using a hydrodynamic challenge model necrotic NS3 DC vaccination resulted in enhanced clearance of NS3-positive hepatocytes from the livers of vaccinated mice. Taken together, the data demonstrate that necrotic DC represent a novel and exciting vaccination strategy capable of inducing broad and multifunctional T cell memory.
Collapse
Affiliation(s)
- Zelalem A Mekonnen
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Makutiro G Masavuli
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Wenbo Yu
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia.,Centre for Cancer Biology, University of South Australia, Adelaide, SA, Australia
| | - Jason Gummow
- Gene Silencing and Expression Laboratory, Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Dawn M Whelan
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Zahraa Al-Delfi
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Joseph Torresi
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Eric J Gowans
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Branka Grubor-Bauk
- Viral Immunology Group, Discipline of Surgery, Basil Hetzel Institute for Translational Medicine, University of Adelaide, Adelaide, SA, Australia
| |
Collapse
|
5
|
Bouskill NJ, Riley WJ, Zhu Q, Mekonnen ZA, Grant RF. Alaskan carbon-climate feedbacks will be weaker than inferred from short-term experiments. Nat Commun 2020; 11:5798. [PMID: 33199687 PMCID: PMC7670472 DOI: 10.1038/s41467-020-19574-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 10/22/2020] [Indexed: 11/08/2022] Open
Abstract
Climate warming is occurring fastest at high latitudes. Based on short-term field experiments, this warming is projected to stimulate soil organic matter decomposition, and promote a positive feedback to climate change. We show here that the tightly coupled, nonlinear nature of high-latitude ecosystems implies that short-term (<10 year) warming experiments produce emergent ecosystem carbon stock temperature sensitivities inconsistent with emergent multi-decadal responses. We first demonstrate that a well-tested mechanistic ecosystem model accurately represents observed carbon cycle and active layer depth responses to short-term summer warming in four diverse Alaskan sites. We then show that short-term warming manipulations do not capture the non-linear, long-term dynamics of vegetation, and thereby soil organic matter, that occur in response to thermal, hydrological, and nutrient transformations belowground. Our results demonstrate significant spatial heterogeneity in multi-decadal Arctic carbon cycle trajectories and argue for more mechanistic models to improve predictive capabilities.
Collapse
Affiliation(s)
- Nicholas J Bouskill
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - William J Riley
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Qing Zhu
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Zelalem A Mekonnen
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Robert F Grant
- Department of Renewable Resources, University of Alberta, Edmonton, Canada
| |
Collapse
|
6
|
Mekonnen ZA, Riley WJ, Randerson JT, Grant RF, Rogers BM. Expansion of high-latitude deciduous forests driven by interactions between climate warming and fire. Nat Plants 2019; 5:952-958. [PMID: 31451797 DOI: 10.1038/s41477-019-0495-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 07/16/2019] [Indexed: 05/12/2023]
Abstract
High-latitude regions have experienced rapid warming in recent decades, and this trend is projected to continue over the twenty-first century1. Fire is also projected to increase with warming2,3. We show here, consistent with changes during the Holocene4, that changes in twenty-first century climate and fire are likely to alter the composition of Alaskan boreal forests. We hypothesize that competition for nutrients after fire in early succession and for light in late succession in a warmer climate will cause shifts in plant functional type. Consistent with observations, our ecosystem model predicts evergreen conifers to be the current dominant tree type in Alaska. However, under future climate and fire, our analysis suggests the relative dominance of deciduous broadleaf trees nearly doubles, accounting for 58% of the Alaska ecosystem's net primary productivity by 2100, with commensurate declines in contributions from evergreen conifer trees and herbaceous plants. Post-fire deciduous broadleaf tree growth under a future climate is sustained from enhanced microbial nitrogen mineralization caused by warmer soils and deeper active layers, resulting in taller trees that compete more effectively for light. The expansion of deciduous broadleaf forests will affect the carbon cycle, surface energy fluxes and ecosystem function, thereby modifying important feedbacks with the climate system.
Collapse
Affiliation(s)
- Zelalem A Mekonnen
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - William J Riley
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - James T Randerson
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Robert F Grant
- Department of Renewable Resources, University of Alberta, Edmonton, Canada
| | | |
Collapse
|
7
|
Shrestha AC, Wijesundara DK, Masavuli MG, Mekonnen ZA, Gowans EJ, Grubor-Bauk B. Cytolytic Perforin as an Adjuvant to Enhance the Immunogenicity of DNA Vaccines. Vaccines (Basel) 2019; 7:vaccines7020038. [PMID: 31052178 PMCID: PMC6630607 DOI: 10.3390/vaccines7020038] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/19/2019] [Accepted: 04/25/2019] [Indexed: 12/21/2022] Open
Abstract
DNA vaccines present one of the most cost-effective platforms to develop global vaccines, which have been tested for nearly three decades in preclinical and clinical settings with some success in the clinic. However, one of the major challenges for the development of DNA vaccines is their poor immunogenicity in humans, which has led to refinements in DNA delivery, dosage in prime/boost regimens and the inclusion of adjuvants to enhance their immunogenicity. In this review, we focus on adjuvants that can enhance the immunogenicity of DNA encoded antigens and highlight the development of a novel cytolytic DNA platform encoding a truncated mouse perforin. The application of this innovative DNA technology has considerable potential in the development of effective vaccines.
Collapse
Affiliation(s)
- Ashish C Shrestha
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| | - Danushka K Wijesundara
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| | - Makutiro G Masavuli
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| | - Zelalem A Mekonnen
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| | - Eric J Gowans
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| | - Branka Grubor-Bauk
- Virology Laboratory, Discipline of Surgery, Basil Hetzel Institute for Translational Health Research and University of Adelaide, Adelaide 5011, Australia.
| |
Collapse
|
8
|
Mekonnen ZA, Grubor-Bauk B, Masavuli MG, Shrestha AC, Ranasinghe C, Bull RA, Lloyd AR, Gowans EJ, Wijesundara DK. Toward DNA-Based T-Cell Mediated Vaccines to Target HIV-1 and Hepatitis C Virus: Approaches to Elicit Localized Immunity for Protection. Front Cell Infect Microbiol 2019; 9:91. [PMID: 31001491 PMCID: PMC6456646 DOI: 10.3389/fcimb.2019.00091] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 03/14/2019] [Indexed: 01/07/2023] Open
Abstract
Human immunodeficiency virus (HIV)-1 and hepatitis C virus (HCV) are major contributors to the global disease burden with many experts recognizing the requirement of an effective vaccine to bring a durable end to these viral epidemics. The most promising vaccine candidates that have advanced into pre-clinical models and the clinic to eliminate or provide protection against these chronic viruses are viral vectors [e.g., recombinant cytomegalovirus, Adenovirus, and modified vaccinia Ankara (MVA)]. This raises the question, is there a need to develop DNA vaccines against HIV-1 and HCV? Since the initial study from Wolff and colleagues which showed that DNA represents a vector that can be used to express transgenes durably in vivo, DNA has been regularly evaluated as a vaccine vector albeit with limited success in large animal models and humans. However, several recent studies in Phase I-IIb trials showed that vaccination of patients with recombinant DNA represents a feasible therapeutic intervention to even cure cervical cancer, highlighting the potential of using DNA for human vaccinations. In this review, we will discuss the limitations and the strategies of using DNA as a vector to develop prophylactic T cell-mediated vaccines against HIV-1 and HCV. In particular, we focus on potential strategies exploiting DNA vectors to elicit protective localized CD8+ T cell immunity in the liver for HCV and in the cervicovaginal mucosa for HIV-1 as localized immunity will be an important, if not critical component, of an efficacious vaccine against these viral infections.
Collapse
Affiliation(s)
- Zelalem A. Mekonnen
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia
| | - Branka Grubor-Bauk
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia
| | - Makutiro G. Masavuli
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia
| | - Ashish C. Shrestha
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia
| | - Charani Ranasinghe
- Molecular Mucosal Vaccine Immunology Group, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Rowena A. Bull
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Andrew R. Lloyd
- Viral Immunology Systems Program, The Kirby Institute, The University of New South Wales, Sydney, NSW, Australia
| | - Eric J. Gowans
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia
| | - Danushka K. Wijesundara
- Virology Laboratory, Basil Hetzel Institute for Translational Health Research, Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia,*Correspondence: Danushka K. Wijesundara
| |
Collapse
|
9
|
Mekonnen ZA, Grant RF, Schwalm C. Sensitivity of modeled NEP to climate forcing and soil at site and regional scales: Implications for upscaling ecosystem models. Ecol Modell 2016. [DOI: 10.1016/j.ecolmodel.2015.10.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|