1
|
Mura M, Misganaw B, Gautam A, Robinson T, Chaudhury S, Bansal N, Martins AJ, Tsang J, Hammamieh R, Bergmann-Leitner E. Human transcriptional signature of protection after Plasmodium falciparum immunization and infectious challenge via mosquito bites. Hum Vaccin Immunother 2023; 19:2282693. [PMID: 38010150 PMCID: PMC10760396 DOI: 10.1080/21645515.2023.2282693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 11/08/2023] [Indexed: 11/29/2023] Open
Abstract
The identification of immune correlates of protection against infectious pathogens will accelerate the design and optimization of recombinant and subunit vaccines. Systematic analyses such as immunoprofiling including serological, cellular, and molecular assessments supported by computational tools are key to not only identify correlates of protection but also biomarkers of disease susceptibility. The current study expands our previous cellular and serological profiling of vaccine-induced responses to a whole parasite malaria vaccine. The irradiated sporozoite model was chosen as it is considered the most effective vaccine against malaria. In contrast to whole blood transcriptomics analysis, we stimulated peripheral blood mononuclear cells (PBMC) with sporozoites and enriched for antigen-specific cells prior to conducting transcriptomics analysis. By focusing on transcriptional events triggered by antigen-specific stimulation, we were able to uncover quantitative and qualitative differences between protected and non-protected individuals to controlled human malaria infections and identified differentially expressed genes associated with sporozoite-specific responses. Further analyses including pathway and gene set enrichment analysis revealed that vaccination with irradiated sporozoites induced a transcriptomic profile associated with Th1-responses, Interferon-signaling, antigen-presentation, and inflammation. Analyzing longitudinal time points not only post-vaccination but also post-controlled human malaria infection further revealed that the transcriptomic profile of protected vs non-protected individuals was not static but continued to diverge over time. The results lay the foundation for comparing protective immune signatures induced by various vaccine platforms to uncover immune correlates of protection that are common across platforms.
Collapse
Affiliation(s)
- Marie Mura
- Immunology Core, Biologics Research & Development, WRAIR-Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Host-Pathogen Interactions, Microbiology and Infectious Diseases, IRBA-Institut de Recherche Biomédicale des Armées, Brétigny-sur-Orge, France
| | - Burook Misganaw
- Medical Readiness Systems Biology, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Vysnova Inc, Landover, MD, USA
| | - Aarti Gautam
- Medical Readiness Systems Biology, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Tanisha Robinson
- Immunology Core, Biologics Research & Development, WRAIR-Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sidhartha Chaudhury
- Center of Enabling Capabilties, WRAIR-Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Neha Bansal
- Multiscale Systems Biology Section, Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, USA
| | - Andrew J. Martins
- Multiscale Systems Biology Section, Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, USA
| | - John Tsang
- Multiscale Systems Biology Section, Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, USA
- NIH Center for Human Immunology, NIAID, NIH, Bethesda, MD, USA
| | - Rasha Hammamieh
- Medical Readiness Systems Biology, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Elke Bergmann-Leitner
- Immunology Core, Biologics Research & Development, WRAIR-Walter Reed Army Institute of Research, Silver Spring, MD, USA
| |
Collapse
|
2
|
Britto C, Alter G. The next frontier in vaccine design: blending immune correlates of protection into rational vaccine design. Curr Opin Immunol 2022; 78:102234. [PMID: 35973352 PMCID: PMC9612370 DOI: 10.1016/j.coi.2022.102234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/27/2022] [Accepted: 07/13/2022] [Indexed: 02/02/2023]
Abstract
Despite the extraordinary speed and success in SARS-Cov-2 vaccine development, the emergence of variants of concern perplexed the vaccine development community. Neutralizing antibodies waned antibodies waned and were evaded by viral variants, despite the preservation of protection against severe disease and death across vaccinated populations. Similar to other vaccine design efforts, the lack of mechanistic correlates of immunity against Coronavirus Disease 2019, raised questions related to the need for vaccine redesign and boosting. Hence, our limited understanding of mechanistic correlates of immunity - across pathogens - remains a major obstacle in vaccine development. The identification and incorporation of mechanistic correlates of immunity are key to the accelerated design of highly impactful globally relevant vaccines. Systems-biology tools can be applied strategically to define a complete understanding of mechanistic correlates of immunity. Embedding immunological dissection and target immune profile identification, beyond canonical antibody binding and neutralization, may accelerate the design and success of durable protective vaccines.
Collapse
Affiliation(s)
- Carl Britto
- Department of Pediatrics, Boston Children's Hospital, USA; Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
| | - Galit Alter
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA.
| |
Collapse
|
3
|
Siddiqui AJ, Bhardwaj J, Hamadou WS, Goyal M, Jahan S, Ashraf SA, Jamal A, Sharma P, Sachidanandan M, Badraoui R, Snoussi M, Adnan M. Impact of chemoprophylaxis immunisation under halofantrine (CPS-HF) drug cover in Plasmodium yoelii Swiss mice malaria model. Folia Parasitol (Praha) 2022; 69. [PMID: 35145048 DOI: 10.14411/fp.2022.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/28/2021] [Indexed: 11/19/2022]
Abstract
In the present study, we have investigated the role of antimalarial drug halofantrine (HF) in inducing the sterile protection against challenges with sporozoites of the live infectious Plasmodium yoelii (Killick-Kendrick, 1967) in Swiss mice malaria model. We observed that during the first to third sequential sporozoite inoculation cycles, blood-stage patency remains the same in the control and chemoprophylaxis under HF drug cover (CPS-HF) groups. However, a delayed blood-stage infection was observed during the fourth and fifth sporozoite challenges and complete sterile protection was produced following the sixth sporozoite challenge in CPS-HF mice. We also noticed a steady decline in liver stage parasite load after 3th to 6th sporozoite challenge cycle in CPS-HF mice. CPS-HF immunisation results in a significant up-regulation of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-12 and iNOS) and down-regulation of anti-inflammatory cytokines (IL-10 and TGF-β) mRNA expression in hepatic mononuclear cells (HMNC) and spleen cells in the immunised CPS-HF mice (after 6th sporozoite challenge) compared to control. Overall, our study suggests that the repetitive sporozoite inoculation under HF drug treatment develops a strong immune response that confers protection against subsequent challenges with sporozoites of P. yoelii.
Collapse
Affiliation(s)
- Arif Jamal Siddiqui
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia.,Molecular Parasitology and Immunology Division, CSIR-Central Drug Research Institute, Lucknow, India.,Both authors have contributed equally to this work and share first authorship.,Corresponding author
| | - Jyoti Bhardwaj
- Indiana University, School of Medicine, Indianapolis, Indiana, United States.,Molecular Parasitology and Immunology Division, CSIR-Central Drug Research Institute, Lucknow, India.,Both authors have contributed equally to this work and share first authorship
| | - Walid Sabri Hamadou
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia
| | - Manish Goyal
- Molecular Parasitology and Immunology Division, CSIR-Central Drug Research Institute, Lucknow, India
| | - Sadaf Jahan
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Al Majmaah, Saudi Arabia
| | - Syed Amir Ashraf
- Department of Clinical Nutrition, College of Applied Medial Sciences, University of Hail, Hail, Saudi Arabia
| | - Arshad Jamal
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia
| | - Pankaj Sharma
- Molecular Parasitology and Immunology Division, CSIR-Central Drug Research Institute, Lucknow, India.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, U.S.A
| | | | - Riadh Badraoui
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia
| | - Mejdi Snoussi
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia
| | - Mohd Adnan
- Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia
| |
Collapse
|
4
|
Immunoprofiling Identifies Functional B and T Cell Subsets Induced by an Attenuated Whole Parasite Malaria Vaccine as Correlates of Sterile Immunity. Vaccines (Basel) 2022; 10:vaccines10010124. [PMID: 35062785 PMCID: PMC8780163 DOI: 10.3390/vaccines10010124] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/06/2022] [Accepted: 01/11/2022] [Indexed: 02/05/2023] Open
Abstract
Immune correlates of protection remain elusive for most vaccines. An identified immune correlate would accelerate the down-selection of vaccine formulations by reducing the need for human pathogen challenge studies that are currently required to determine vaccine efficacy. Immunization via mosquito-delivered, radiation-attenuated P. falciparum sporozoites (IMRAS) is a well-established model for efficacious malaria vaccines, inducing greater than 90% sterile immunity. The current immunoprofiling study utilized samples from a clinical trial in which vaccine dosing was adjusted to achieve only 50% protection, thus enabling a comparison between protective and non-protective immune signatures. In-depth immunoprofiling was conducted by assessing a wide range of antigen-specific serological and cellular parameters and applying our newly developed computational tools, including machine learning. The computational component of the study pinpointed previously un-identified cellular T cell subsets (namely, TNFα-secreting CD8+CXCR3−CCR6− T cells, IFNγ-secreting CD8+CCR6+ T cells and TNFα/FNγ-secreting CD4+CXCR3−CCR6− T cells) and B cell subsets (i.e., CD19+CD24hiCD38hiCD69+ transitional B cells) as important factors predictive of protection (92% accuracy). Our study emphasizes the need for in-depth immunoprofiling and subsequent data integration with computational tools to identify immune correlates of protection. The described process of computational data analysis is applicable to other disease and vaccine models.
Collapse
|
5
|
Lefebvre MN, Drewry LL, Pewe LL, Hancox LS, Reyes-Sandoval A, Harty JT. Cutting Edge: Subunit Booster Vaccination Confers Sterilizing Immunity against Liver-Stage Malaria in Mice Initially Primed with a Weight-Normalized Dose of Radiation-Attenuated Sporozoites. THE JOURNAL OF IMMUNOLOGY 2021; 207:2631-2635. [PMID: 34716185 DOI: 10.4049/jimmunol.2100818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/25/2021] [Indexed: 11/19/2022]
Abstract
Radiation-attenuated sporozoite (RAS) vaccination offers hope for global malaria control through induction of protective liver-stage-specific memory CD8 T cells. Effective RAS vaccination regimens exist; however, widespread implementation remains unfeasible. A key difficulty resides in the need to administer three or more doses i.v. to achieve sufficient immunity. Strategies to reduce the number of RAS doses are therefore desirable. Here we used mice to model human immune responses to a single, suboptimal weight-normalized RAS dose administered i.v. followed by subunit vaccination to amplify liver-stage-specific memory CD8 T cells. RAS+subunit prime-boost regimens increased the numbers of liver-stage-specific memory CD8 T cells to a level greater than is present after one RAS vaccination. Both i.v. and i.m. subunit vaccine delivery induced immunity in mice, and many vaccinated mice completely cleared liver infection. These findings are particularly relevant to human vaccine development because RAS+subunit prime-boost vaccination would reduce the logistical challenges of multiple RAS-only immunizations.
Collapse
Affiliation(s)
- Mitchell N Lefebvre
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Medical Scientist Training Program, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA; and
| | - Lisa L Drewry
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Lecia L Pewe
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Lisa S Hancox
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | | | - John T Harty
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA; .,Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA; and
| |
Collapse
|
6
|
Lefebvre MN, Surette FA, Anthony SM, Vijay R, Jensen IJ, Pewe LL, Hancox LS, Van Braeckel-Budimir N, van de Wall S, Urban SL, Mix MR, Kurup SP, Badovinac VP, Butler NS, Harty JT. Expeditious recruitment of circulating memory CD8 T cells to the liver facilitates control of malaria. Cell Rep 2021; 37:109956. [PMID: 34731605 PMCID: PMC8628427 DOI: 10.1016/j.celrep.2021.109956] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/08/2021] [Accepted: 10/15/2021] [Indexed: 12/15/2022] Open
Abstract
Circulating memory CD8 T cell trafficking and protective capacity during liver-stage malaria infection remains undefined. We find that effector memory CD8 T cells (Tem) infiltrate the liver within 6 hours after malarial or bacterial infections and mediate pathogen clearance. Tem recruitment coincides with rapid transcriptional upregulation of inflammatory genes in Plasmodium-infected livers. Recruitment requires CD8 T cell-intrinsic LFA-1 expression and the presence of liver phagocytes. Rapid Tem liver infiltration is distinct from recruitment to other non-lymphoid tissues in that it occurs both in the absence of liver tissue resident memory "sensing-and-alarm" function and ∼42 hours earlier than in lung infection by influenza virus. These data demonstrate relevance for Tem in protection against malaria and provide generalizable mechanistic insights germane to control of liver infections.
Collapse
Affiliation(s)
- Mitchell N Lefebvre
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Medical Scientist Training Program, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA
| | - Fionna A Surette
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA; Department of Microbiology and Immunology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Scott M Anthony
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Rahul Vijay
- Department of Microbiology and Immunology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Isaac J Jensen
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA
| | - Lecia L Pewe
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Lisa S Hancox
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | | | - Stephanie van de Wall
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Stina L Urban
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Madison R Mix
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Medical Scientist Training Program, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA
| | - Samarchith P Kurup
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Vladimir P Badovinac
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA; Department of Microbiology and Immunology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - Noah S Butler
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA; Department of Microbiology and Immunology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA
| | - John T Harty
- Department of Pathology, University of Iowa, Carver College of Medicine, Iowa City, IA 52246, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52246, USA.
| |
Collapse
|
7
|
Chemoprophylaxis under sporozoites-lumefantrine (CPS-LMF) immunization induce protective immune responses against Plasmodium yoelii sporozoites infection in mice. 3 Biotech 2021; 11:465. [PMID: 34745816 DOI: 10.1007/s13205-021-03022-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/06/2021] [Indexed: 01/16/2023] Open
Abstract
Malaria represents one of the major life-threatening diseases that poses a huge socio-economic impact, worldwide. Chemoprophylaxis vaccination using a relatively low number of wild-type infectious sporozoites represents an attractive and effective vaccine strategy against malaria. However, the role of immune responses to pre-erythrocytic versus blood-stage parasites in protection against different antimalarial drugs remains unclear. Here, in the present study, we explored the immune responses against the repetitive inoculation of live Plasmodium yoelii (P. yoelii) sporozoites in an experimental Swiss mouse model under antimalarial drug lumefantrine chemoprophylaxis (CPS-LMF). We monitored the liver stage parasitic load, pro/anti-inflammatory cytokines expression, and erythrocytic stage patency, following repetitive cycles of sporozoites inoculations. It was found that repetitive sporozoites inoculation under CPS-LMF results in delayed blood-stage infection during the fourth sporozoites challenge, while sterile protection was produced in mice following the fifth cycle of sporozoites challenge. Intriguingly, we observed a significant up-regulation of pro-inflammatory cytokines (IFN-γ, TNF-α and IL-12) and iNOS response and down-regulation of anti-inflammatory cytokines (IL-4, IL-10 and TGF-β) in the liver HMNC (hepatic mononuclear cells) and spleen cells after 4th and 5th cycle of sporozoites challenge in the CPS-LMF mice. Meanwhile, we also noticed that the liver stage parasites load under CPS-LMF immunization has gradually reduced after 2nd, 3rd, 4th and 5th sporozoites challenge. Overall, our study suggests that chemoprophylaxis vaccination under LMF drug cover develops strong immune responses and confer superior long-lasting protection against P. yoelii sporozoites. Furthermore, this vaccination strategy can be used to study the protective and stage-specific immunity against new protective antigens. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-03022-0.
Collapse
|
8
|
Reeder SM, Bah MA, Tursi NJ, Brooks RC, Patel A, Esquivel R, Eaton A, Jhun H, Chu J, Kim K, Xu Z, Zavala F, Weiner DB. Strategic Variants of CSP Delivered as SynDNA Vaccines Demonstrate Heterogeneity of Immunogenicity and Protection from Plasmodium Infection in a Murine Model. Infect Immun 2021; 89:e0072820. [PMID: 34152830 PMCID: PMC8445182 DOI: 10.1128/iai.00728-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 05/27/2021] [Indexed: 11/20/2022] Open
Abstract
Malaria infects millions of people every year, and despite recent advances in controlling disease spread, such as vaccination, it remains a global health concern. The circumsporozoite protein (CSP) has long been acknowledged as a key target in antimalarial immunity. Leveraging the DNA vaccine platform against this formidable pathogen, the following five synthetic DNA vaccines encoding variations of CSP were designed and studied: 3D7, GPI1, ΔGPI, TM, and DD2. Among the single CSP antigen constructs, a range of immunogenicity was observed with ΔGPI generating the most robust immunity. In an intravenous (i.v.) sporozoite challenge, the best protection among vaccinated mice was achieved by ΔGPI, which performed almost as well as the monoclonal antibody 311 (MAb 311) antibody control. Further analyses revealed that ΔGPI develops high-molecular-weight multimers in addition to monomeric CSP. We then compared the immunity generated by ΔGPI versus synDNA mimics for the antimalaria vaccines RTS,S and R21. The anti-CSP antibody responses induced were similar among these three immunogens. T cell responses demonstrated that ΔGPI induced a more focused anti-CSP response. In an infectious mosquito challenge, all three of these constructs generated inhibition of liver-stage infection as well as immunity from blood-stage parasitemia. This study demonstrates that synDNA mimics of complex malaria immunogens can provide substantial protection as can a novel synDNA vaccine ΔGPI.
Collapse
Affiliation(s)
- Sophia M. Reeder
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Mamadou A. Bah
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Nicholas J. Tursi
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Rebekah C. Brooks
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Ami Patel
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Rianne Esquivel
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Alison Eaton
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Hugo Jhun
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Jacqueline Chu
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Kevin Kim
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Ziyang Xu
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - David B. Weiner
- The Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- The Vaccine Center, Wistar Institute, Philadelphia, Pennsylvania, USA
| |
Collapse
|
9
|
Importance of the Immunodominant CD8 + T Cell Epitope of Plasmodium berghei Circumsporozoite Protein in Parasite- and Vaccine-Induced Protection. Infect Immun 2020; 88:IAI.00383-20. [PMID: 32719159 DOI: 10.1128/iai.00383-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 07/22/2020] [Indexed: 12/15/2022] Open
Abstract
The circumsporozoite protein (CSP) builds up the surface coat of sporozoites and is the leading malaria pre-erythrocytic-stage vaccine candidate. CSP has been shown to induce robust CD8+ T cell responses that are capable of eliminating developing parasites in hepatocytes, resulting in protective immunity. In this study, we characterized the importance of the immunodominant CSP-derived epitope SYIPSAEKI of Plasmodium berghei in both sporozoite- and vaccine-induced protection in murine infection models. In BALB/c mice, where SYIPSAEKI is efficiently presented in the context of the major histocompatibility complex class I (MHC-I) molecule H-2-Kd, we established that epitope-specific CD8+ T cell responses contribute to parasite killing following sporozoite immunization. Yet, sterile protection was achieved in the absence of this epitope, substantiating the concept that other antigens can be sufficient for parasite-induced protective immunity. Furthermore, we demonstrated that SYIPSAEKI-specific CD8+ T cell responses elicited by viral-vectored CSP-expressing vaccines effectively targeted parasites in hepatocytes. The resulting sterile protection strictly relied on the expression of SYIPSAEKI. In C57BL/6 mice, which are unable to present the immunodominant epitope, CSP-based vaccines did not confer complete protection, despite the induction of high levels of CSP-specific antibodies. These findings underscore the significance of CSP in protection against malaria pre-erythrocytic stages and demonstrate that a significant proportion of the protection against the parasite is mediated by CD8+ T cells specific for the immunodominant CSP-derived epitope.
Collapse
|
10
|
Lefebvre MN, Harty JT. You Shall Not Pass: Memory CD8 T Cells in Liver-Stage Malaria. Trends Parasitol 2019; 36:147-157. [PMID: 31843536 DOI: 10.1016/j.pt.2019.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 12/15/2022]
Abstract
Each year over 200 million malaria infections occur, with over 400 000 associated deaths. Vaccines formed with attenuated whole parasites can induce protective memory CD8 T cell responses against liver-stage malaria; however, widespread administration of such vaccines is logistically challenging. Recent scientific findings are delineating how protective memory CD8 T cell populations are primed and maintained and how such cells mediate immunity to liver-stage malaria. Memory CD8 T cell anatomic localization and expression of transcription factors, homing receptors, and signaling molecules appear to play integral roles in protective immunity to liver-stage malaria. Further investigation of how such factors contribute to optimal protective memory CD8 T cell generation and maintenance in humans will inform efforts for improved vaccines.
Collapse
Affiliation(s)
- Mitchell N Lefebvre
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA
| | - John T Harty
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA; Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, USA; Department of Pathology, University of Iowa, Iowa City, IA, USA.
| |
Collapse
|
11
|
Plotkin SA. Updates on immunologic correlates of vaccine-induced protection. Vaccine 2019; 38:2250-2257. [PMID: 31767462 DOI: 10.1016/j.vaccine.2019.10.046] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 02/06/2023]
Abstract
Correlates of protection (CoPs) are increasingly important in the development and licensure of vaccines. Although the study of CoPs was initially directed at identifying a single immune function that could explain vaccine efficacy, it has become increasingly clear that there are often multiple functions responsible for efficacy. This review is meant to supplement prior articles on the subject, illustrating both simple and complex CoPs.
Collapse
Affiliation(s)
- Stanley A Plotkin
- Emeritus Professor of Pediatrics, University of Pennsylvania, Vaxconsult, 4650 Wismer Rd., Doylestown, PA 18902, United States.
| |
Collapse
|
12
|
Narula AK, Azad CS, Nainwal LM. New dimensions in the field of antimalarial research against malaria resurgence. Eur J Med Chem 2019; 181:111353. [DOI: 10.1016/j.ejmech.2019.05.043] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/16/2019] [Accepted: 05/15/2019] [Indexed: 12/20/2022]
|
13
|
Odorizzi PM, Jagannathan P, McIntyre TI, Budker R, Prahl M, Auma A, Burt TD, Nankya F, Nalubega M, Sikyomu E, Musinguzi K, Naluwu K, Kakuru A, Dorsey G, Kamya MR, Feeney ME. In utero priming of highly functional effector T cell responses to human malaria. Sci Transl Med 2019; 10:10/463/eaat6176. [PMID: 30333241 DOI: 10.1126/scitranslmed.aat6176] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/10/2018] [Accepted: 09/17/2018] [Indexed: 12/14/2022]
Abstract
Malaria remains a significant cause of morbidity and mortality worldwide, particularly in infants and children. Some studies have reported that exposure to malaria antigens in utero results in the development of tolerance, which could contribute to poor immunity to malaria in early life. However, the effector T cell response to pathogen-derived antigens encountered in utero, including malaria, has not been well characterized. Here, we assessed the frequency, phenotype, and function of cord blood T cells from Ugandan infants born to mothers with and without placental malaria. We found that infants born to mothers with active placental malaria had elevated frequencies of proliferating effector memory fetal CD4+ T cells and higher frequencies of CD4+ and CD8+ T cells that produced inflammatory cytokines. Fetal CD4+ and CD8+ T cells from placental malaria-exposed infants exhibited greater in vitro proliferation to malaria antigens. Malaria-specific CD4+ T cell proliferation correlated with prospective protection from malaria during childhood. These data demonstrate that placental malaria is associated with the generation of proinflammatory malaria-responsive fetal T cells. These findings add to our current understanding of fetal immunity and indicate that a functional and protective pathogen-specific T cell response can be generated in utero.
Collapse
Affiliation(s)
- Pamela M Odorizzi
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | | | - Tara I McIntyre
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Rachel Budker
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Mary Prahl
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Ann Auma
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Trevor D Burt
- Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA.,Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143, USA
| | | | | | - Esther Sikyomu
- Infectious Disease Research Collaboration, Kampala, Uganda
| | | | - Kate Naluwu
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Abel Kakuru
- Infectious Disease Research Collaboration, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA
| | - Moses R Kamya
- School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Margaret E Feeney
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110 USA. .,Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA
| |
Collapse
|
14
|
Sanasam BD, Kumar S. PRE-binding protein of Plasmodium falciparum is a potential candidate for vaccine design and development: An in silico evaluation of the hypothesis. Med Hypotheses 2019; 125:119-123. [DOI: 10.1016/j.mehy.2019.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 12/14/2018] [Accepted: 01/10/2019] [Indexed: 11/29/2022]
|
15
|
Cooper MM, Loiseau C, McCarthy JS, Doolan DL. Human challenge models: tools to accelerate the development of malaria vaccines. Expert Rev Vaccines 2019; 18:241-251. [PMID: 30732492 DOI: 10.1080/14760584.2019.1580577] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Malaria challenge models, where healthy human volunteers are intentionally infected with Plasmodium species parasites under controlled conditions, can be undertaken in several well-defined ways. These challenge models enable evaluation of the kinetics of parasite growth and clearance, host-pathogen interactions and the host immune response. They can facilitate discovery of candidate diagnostic biomarkers and novel vaccine targets. As translational tools they can facilitate testing of candidate vaccines and drugs and evaluation of diagnostic tests. AREAS COVERED Until recently, malaria human challenge models have been limited to only a few Plasmodium falciparum strains and used exclusively in malaria-naïve volunteers in non-endemic regions. Several recent advances include the use of alternate P. falciparum strains and other species of Plasmodia, as well as strains attenuated by chemical, radiation or genetic modification, and the conduct of studies in pre-exposed individuals. Herein, we discuss how this diversification is enabling more thorough vaccine efficacy testing and informing rational vaccine development. EXPERT OPINION The ability to comprehensively evaluate vaccine efficacy in controlled settings will continue to accelerate the translation of candidate malaria vaccines to the clinic, and inform the development and optimisation of potential vaccines that would be effective against multiple strains in geographically and demographically diverse settings.
Collapse
Affiliation(s)
- Martha M Cooper
- a Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine , James Cook University , Cairns , Australia
| | - Claire Loiseau
- a Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine , James Cook University , Cairns , Australia
| | - James S McCarthy
- b Infectious Diseases Programme , QIMR Berghofer Medical Research Institute , Brisbane , Australia
| | - Denise L Doolan
- a Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine , James Cook University , Cairns , Australia
| |
Collapse
|
16
|
Abstract
The development of highly effective and durable vaccines against the human malaria parasites Plasmodium falciparum and P. vivax remains a key priority. Decades of endeavor have taught that achieving this goal will be challenging; however, recent innovation in malaria vaccine research and a diverse pipeline of novel vaccine candidates for clinical assessment provides optimism. With first-generation pre-erythrocytic vaccines aiming for licensure in the coming years, it is important to reflect on how next-generation approaches can improve on their success. Here we review the latest vaccine approaches that seek to prevent malaria infection, disease, and transmission and highlight some of the major underlying immunological and molecular mechanisms of protection. The synthesis of rational antigen selection, immunogen design, and immunization strategies to induce quantitatively and qualitatively improved immune effector mechanisms offers promise for achieving sustained high-level protection.
Collapse
|
17
|
Itsara LS, Zhou Y, Do J, Grieser AM, Vaughan AM, Ghosh AK. The Development of Whole Sporozoite Vaccines for Plasmodium falciparum Malaria. Front Immunol 2018; 9:2748. [PMID: 30619241 PMCID: PMC6297750 DOI: 10.3389/fimmu.2018.02748] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 11/08/2018] [Indexed: 12/20/2022] Open
Abstract
Each year malaria kills hundreds of thousands of people and infects hundreds of millions of people despite current control measures. An effective malaria vaccine will likely be necessary to aid in malaria eradication. Vaccination using whole sporozoites provides an increased repertoire of immunogens compared to subunit vaccines across at least two life cycle stages of the parasite, the extracellular sporozoite, and intracellular liver stage. Three potential whole sporozoite vaccine approaches are under development and include genetically attenuated parasites, radiation attenuated sporozoites, and wild-type sporozoites administered in combination with chemoprophylaxis. Pre-clinical and clinical studies have demonstrated whole sporozoite vaccine immunogenicity, including humoral and cellular immunity and a range of vaccine efficacy that depends on the pre-exposure of vaccinated individuals. While whole sporozoite vaccines can provide protection against malaria in some cases, more recent studies in malaria-endemic regions demonstrate the need for improvements. Moreover, challenges remain in manufacturing large quantities of sporozoites for vaccine commercialization. A promising solution to the whole sporozoite manufacturing challenge is in vitro culturing methodology, which has been described for several Plasmodium species, including the major disease-causing human malaria parasite, Plasmodium falciparum. Here, we review whole sporozoite vaccine immunogenicity and in vitro culturing platforms for sporozoite production.
Collapse
Affiliation(s)
| | | | - Julie Do
- MalarVx, Inc., Seattle, WA, United States
| | | | - Ashley M Vaughan
- Seattle Children's Research Institute, Seattle, WA, United States
| | | |
Collapse
|
18
|
Othman AS, Franke-Fayard BM, Imai T, van der Gracht ETI, Redeker A, Salman AM, Marin-Mogollon C, Ramesar J, Chevalley-Maurel S, Janse CJ, Arens R, Khan SM. OX40 Stimulation Enhances Protective Immune Responses Induced After Vaccination With Attenuated Malaria Parasites. Front Cell Infect Microbiol 2018; 8:247. [PMID: 30073152 PMCID: PMC6060232 DOI: 10.3389/fcimb.2018.00247] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/28/2018] [Indexed: 01/15/2023] Open
Abstract
Protection against a malaria infection can be achieved by immunization with live-attenuated Plasmodium sporozoites and while the precise mechanisms of protection remain unknown, T cell responses are thought to be critical in the elimination of infected liver cells. In cancer immunotherapies, agonistic antibodies that target T cell surface proteins, such as CD27, OX40 (CD134), and 4-1BB (CD137), have been used to enhance T cell function by increasing co-stimulation. In this study, we have analyzed the effect of agonistic OX40 monoclonal antibody treatment on protective immunity induced in mice immunized with genetically attenuated parasites (GAPs). OX40 stimulation enhanced protective immunity after vaccination as shown by an increase in the number of protected mice and delay to blood-stage infection after challenge with wild-type sporozoites. Consistent with the enhanced protective immunity enforced OX40 stimulation resulted in an increased expansion of antigen-experienced effector (CD11ahiCD44hi) CD8+ and CD4+ T cells in the liver and spleen and also increased IFN-γ and TNF producing CD4+ T cells in the liver and spleen. In addition, GAP immunization plus α-OX40 treatment significantly increased sporozoite-specific IgG responses. Thus, we demonstrate that targeting T cell costimulatory receptors can improve sporozoite-based vaccine efficacy.
Collapse
Affiliation(s)
- Ahmad Syibli Othman
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands.,Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Terengganu, Malaysia
| | - Blandine M Franke-Fayard
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Takashi Imai
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Esmé T I van der Gracht
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, Netherlands
| | - Anke Redeker
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, Netherlands
| | - Ahmed M Salman
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands.,The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Catherin Marin-Mogollon
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Jai Ramesar
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | | | - Chris J Janse
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Ramon Arens
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, Netherlands
| | - Shahid M Khan
- Leiden Malaria Research Group, Parasitology, Leiden University Medical Center, Leiden, Netherlands
| |
Collapse
|
19
|
Dhume K, McKinstry KK. Early programming and late-acting checkpoints governing the development of CD4 T-cell memory. Immunology 2018; 155:53-62. [PMID: 29701246 DOI: 10.1111/imm.12942] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 12/25/2022] Open
Abstract
CD4 T cells contribute to protection against pathogens through numerous mechanisms. Incorporating the goal of memory CD4 T-cell generation into vaccine strategies therefore offers a powerful approach to improve their efficacy, especially in situations where humoral responses alone cannot confer long-term immunity. These threats include viruses such as influenza that mutate coat proteins to avoid neutralizing antibodies, but that are targeted by T cells that recognize more conserved protein epitopes shared by different strains. A major barrier in the design of such vaccines is that the mechanisms controlling the efficiency with which memory cells form remain incompletely understood. Here, we discuss recent insights into fate decisions controlling memory generation. We focus on the importance of three general cues: interleukin-2, antigen and co-stimulatory interactions. It is increasingly clear that these signals have a powerful influence on the capacity of CD4 T cells to form memory during two distinct phases of the immune response. First, through 'programming' that occurs during initial priming, and second, through 'checkpoints' that operate later during the effector stage. These findings indicate that novel vaccine strategies must seek to optimize cognate interactions, during which interleukin-2-, antigen- and co-stimulation-dependent signals are tightly linked, well beyond initial antigen encounter to induce robust memory CD4 T cells.
Collapse
Affiliation(s)
- Kunal Dhume
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Karl Kai McKinstry
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| |
Collapse
|
20
|
Modeling the effect of boost timing in murine irradiated sporozoite prime-boost vaccines. PLoS One 2018; 13:e0190940. [PMID: 29329308 PMCID: PMC5766151 DOI: 10.1371/journal.pone.0190940] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 12/22/2017] [Indexed: 11/29/2022] Open
Abstract
Vaccination with radiation-attenuated sporozoites has been shown to induce CD8+ T cell-mediated protection against pre-erythrocytic stages of malaria. Empirical evidence suggests that successive inoculations often improve the efficacy of this type of vaccines. An initial dose (prime) triggers a specific cellular response, and subsequent inoculations (boost) amplify this response to create a robust CD8+ T cell memory. In this work we propose a model to analyze the effect of T cell dynamics on the performance of prime-boost vaccines. This model suggests that boost doses and timings should be selected according to the T cell response elicited by priming. Specifically, boosting during late stages of clonal contraction would maximize T cell memory production for vaccines using lower doses of irradiated sporozoites. In contrast, single-dose inoculations would be indicated for higher vaccine doses. Experimental data have been obtained that support theoretical predictions of the model.
Collapse
|
21
|
Sack BK, Mikolajczak SA, Fishbaugher M, Vaughan AM, Flannery EL, Nguyen T, Betz W, Jane Navarro M, Foquet L, Steel RWJ, Billman ZP, Murphy SC, Hoffman SL, Chakravarty S, Sim BKL, Behet M, Reuling IJ, Walk J, Scholzen A, Sauerwein RW, Ishizuka AS, Flynn B, Seder RA, Kappe SHI. Humoral protection against mosquito bite-transmitted Plasmodium falciparum infection in humanized mice. NPJ Vaccines 2017; 2:27. [PMID: 29263882 PMCID: PMC5634440 DOI: 10.1038/s41541-017-0028-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 07/25/2017] [Accepted: 09/07/2017] [Indexed: 01/05/2023] Open
Abstract
A malaria vaccine that prevents infection will be an important new tool in continued efforts of malaria elimination, and such vaccines are under intense development for the major human malaria parasite Plasmodium falciparum (Pf). Antibodies elicited by vaccines can block the initial phases of parasite infection when sporozoites are deposited into the skin by mosquito bite and then target the liver for further development. However, there are currently no standardized in vivo preclinical models that can measure the inhibitory activity of antibody specificities against Pf sporozoite infection via mosquito bite. Here, we use human liver-chimeric mice as a challenge model to assess prevention of natural Pf sporozoite infection by antibodies. We demonstrate that these mice are consistently infected with Pf by mosquito bite and that this challenge can be combined with passive transfer of either monoclonal antibodies or polyclonal human IgG from immune serum to measure antibody-mediated blocking of parasite infection using bioluminescent imaging. This methodology is useful to down-select functional antibodies and to investigate mechanisms or immune correlates of protection in clinical trials, thereby informing rational vaccine optimization.
Collapse
Affiliation(s)
| | | | | | | | | | - Thao Nguyen
- Center for Infectious Disease Research, Seattle, WA USA
| | - Will Betz
- Center for Infectious Disease Research, Seattle, WA USA
| | | | - Lander Foquet
- Center for Infectious Disease Research, Seattle, WA USA
| | | | - Zachary P. Billman
- Departments of Laboratory Medicine and Microbiology and the Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA USA
| | - Sean C. Murphy
- Center for Infectious Disease Research, Seattle, WA USA
- Departments of Laboratory Medicine and Microbiology and the Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA USA
| | | | | | | | | | | | - Jona Walk
- Radboud University, Nijmegen, The Netherlands
| | | | | | | | | | | | - Stefan H. I. Kappe
- Center for Infectious Disease Research, Seattle, WA USA
- Department of Global Health, University of Washington, Seattle, WA USA
| |
Collapse
|
22
|
Vaughan AM, Kappe SHI. Malaria Parasite Liver Infection and Exoerythrocytic Biology. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a025486. [PMID: 28242785 DOI: 10.1101/cshperspect.a025486] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In their infection cycle, malaria parasites undergo replication and population expansions within the vertebrate host and the mosquito vector. Host infection initiates with sporozoite invasion of hepatocytes, followed by a dramatic parasite amplification event during liver stage parasite growth and replication within hepatocytes. Each liver stage forms up to 90,000 exoerythrocytic merozoites, which are in turn capable of initiating a blood stage infection. Liver stages not only exploit host hepatocyte resources for nutritional needs but also endeavor to prevent hepatocyte cell death and detection by the host's immune system. Research over the past decade has identified numerous parasite factors that play a critical role during liver infection and has started to delineate a complex web of parasite-host interactions that sustain successful parasite colonization of the mammalian host. Targeting the parasites' obligatory infection of the liver as a gateway to the blood, with drugs and vaccines, constitutes the most effective strategy for malaria eradication, as it would prevent clinical disease and onward transmission of the parasite.
Collapse
Affiliation(s)
- Ashley M Vaughan
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington 98109
| | - Stefan H I Kappe
- Center for Infectious Disease Research, formerly Seattle Biomedical Research Institute, Seattle, Washington 98109.,Department of Global Health, University of Washington, Seattle, Washington 98195
| |
Collapse
|
23
|
Zhang M, Kaneko I, Tsao T, Mitchell R, Nardin EH, Iwanaga S, Yuda M, Tsuji M. A highly infectious Plasmodium yoelii parasite, bearing Plasmodium falciparum circumsporozoite protein. Malar J 2016; 15:201. [PMID: 27068454 PMCID: PMC4828769 DOI: 10.1186/s12936-016-1248-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/30/2016] [Indexed: 12/31/2022] Open
Abstract
Background Plasmodium circumsporozoite protein (CSP) is a major surface antigen present in the sporozoite (Spz) stage of a malaria parasite. RTS, S vaccine, the most clinically advanced malaria vaccine, consists of a large portion of Plasmodium falciparum CSP (PfCSP). A highly infectious, recombinant rodent malaria, Plasmodium yoelii parasite bearing a full-length PfCSP, PfCSP/Py Spz, was needed as a tool to evaluate the role of PfCSP in mediating, protective, anti-malaria immunity in a mouse model. Methods A transgenic parasite, PfCSP/Py Spz, was generated by inserting a construct expressing the PfCSP at the locus of the P. yoelii CSP gene by double cross-over homologous recombination. Then the biological and protective properties of PfCSP/Py Spz were determined. Results This PfCSP/Py parasite produced up to 30,000 Spz in mosquito salivary glands, which is equal or even higher than the number of Spz produced by wild-type P. yoelii parasites. Five bites of PfCSP/Py-infected mosquitoes could induce blood infection in BALB/c mice. Conclusions The current study has demonstrated a successful establishment of a transgenic P. yoelii parasite clone that is able to express a full-length PfCSP, PfCSP/Py parasite. Importantly, this PfCSP/Py parasite can be as infectious as the wild-type P. yoelii parasite both in mosquito vector and in mouse, a mammalian host. A new transgenic parasite that expresses a full-length PfCSP may become a useful tool for researchers to investigate immunity against PfCSP in a mouse model.
Collapse
Affiliation(s)
- Min Zhang
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA.,Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Izumi Kaneko
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Tiffany Tsao
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA
| | - Robert Mitchell
- Division of Parasitology, Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Elizabeth H Nardin
- Division of Parasitology, Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Shiroh Iwanaga
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
| | - Masao Yuda
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
| | - Moriya Tsuji
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA.
| |
Collapse
|
24
|
Abstract
With increasing malaria control and goals of malaria elimination, many endemic areas are transitioning from high-to-low-to-no malaria transmission. Reductions in transmission will impact on the development of naturally acquired immunity to malaria, which develops after repeated exposure to Plasmodium spp. However, it is currently unclear how declining transmission and malaria exposure will affect the development and maintenance of naturally acquired immunity. Here we review the key processes which underpin this knowledge; the amount of Plasmodium spp. exposure required to generate effective immune responses, the longevity of antibody responses and the ability to mount an effective response upon re-exposure through memory responses. Lastly we identify research priorities which will increase our understanding of how changing transmission will impact on malarial immunity.
Collapse
|
25
|
Martins KAO, Cooper CL, Stronsky SM, Norris SLW, Kwilas SA, Steffens JT, Benko JG, van Tongeren SA, Bavari S. Adjuvant-enhanced CD4 T Cell Responses are Critical to Durable Vaccine Immunity. EBioMedicine 2015; 3:67-78. [PMID: 26870818 PMCID: PMC4739439 DOI: 10.1016/j.ebiom.2015.11.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/23/2015] [Accepted: 11/24/2015] [Indexed: 01/08/2023] Open
Abstract
Protein-based vaccines offer a safer alternative to live-attenuated or inactivated vaccines but have limited immunogenicity. The identification of adjuvants that augment immunogenicity, specifically in a manner that is durable and antigen-specific, is therefore critical for advanced development. In this study, we use the filovirus virus-like particle (VLP) as a model protein-based vaccine in order to evaluate the impact of four candidate vaccine adjuvants on enhancing long term protection from Ebola virus challenge. Adjuvants tested include poly-ICLC (Hiltonol), MPLA, CpG 2395, and alhydrogel. We compared and contrasted antibody responses, neutralizing antibody responses, effector T cell responses, and T follicular helper (Tfh) cell frequencies with each adjuvant's impact on durable protection. We demonstrate that in this system, the most effective adjuvant elicits a Th1-skewed antibody response and strong CD4 T cell responses, including an increase in Tfh frequency. Using immune-deficient animals and adoptive transfer of serum and cells from vaccinated animals into naïve animals, we further demonstrate that serum and CD4 T cells play a critical role in conferring protection within effective vaccination regimens. These studies inform on the requirements of long term immune protection, which can potentially be used to guide screening of clinical-grade adjuvants for vaccine clinical development. Adjuvants can prolong the protection afforded by protein-based vaccines and impact adaptive immune responses Enhanced CD4 T cell responses, helper and effector, correlate with duration of protection Durable protection from ma-EBOV is associated with Tfh frequency, Th1 antibody titers, and effector CD4 T cells
Protein-based vaccines are extremely safe, but they sometimes require the addition of adjuvants to enhance immunogenicity. In this study, we compared the impact of multiple adjuvants on immunogenicity, focusing on the duration of vaccine-mediated protection in mice. We then looked at how each adjuvant impacted the immune response in order to identify correlates of that long lasting immunity. The most effective adjuvant/vaccine combinations elicited multifunctional CD4 T cell responses and a Th1-skewed antibody response. By transferring antigen-experienced CD4 T cells and serum into naïve animals, we demonstrated that both CD4 T cells and serum were critical for durable vaccine-mediated protection.
Collapse
Key Words
- Adjuvant
- BME, beta mercaptoethanol
- CD, cluster of differentiation
- DSCF, Dwass, Steel, Critchlow-Fligner
- Durable protection
- ELISA, Enzyme linked immunosorbent assay
- ELISPOT, enzyme-linked immunospot assay
- Ebola virus
- FACS, fluorescence activated cell sorting
- FBS, fetal bovine serum
- GP, glycoprotein
- IACUC, Institutional Animal Care and Use Committee
- IM, intramuscular
- IP, intraperitoneal
- IQR, interquartile range
- Immune correlates
- LN, lymph node
- MPLA, monophosphoryl lipid A
- NAb, neutralizing antibody
- Ns, not significant
- PBS, phosphate buffered saline
- PRR, pattern recognition receptor
- Pfu, plaque forming unit
- PsVNA, pseudovirion neutralization assay
- TLR, Toll-like receptor
- USAMRIID, United States Army Medical Research Institute of Infectious Diseases
- VLP, virus-like particle
- Vaccine
- ma-EBOV, mouse-adapted Ebola virus
Collapse
Affiliation(s)
- Karen A O Martins
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Christopher L Cooper
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Sabrina M Stronsky
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Sarah L W Norris
- Research Support Division, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Steven A Kwilas
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Jesse T Steffens
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Jacqueline G Benko
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Sean A van Tongeren
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA
| | - Sina Bavari
- Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, USA.
| |
Collapse
|
26
|
Parra M, Liu X, Derrick SC, Yang A, Molina-Cruz A, Barillas-Mury C, Zheng H, Thao Pham P, Sedegah M, Belmonte A, Litilit DD, Waldmann TA, Kumar S, Morris SL, Perera LP. Co-expression of Interleukin-15 Enhances the Protective Immune Responses Induced by Immunization with a Murine Malaria MVA-Based Vaccine Encoding the Circumsporozoite Protein. PLoS One 2015; 10:e0141141. [PMID: 26505634 PMCID: PMC4624717 DOI: 10.1371/journal.pone.0141141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 10/04/2015] [Indexed: 01/01/2023] Open
Abstract
Malaria remains a major global public health problem with an estimated 200 million cases detected in 2012. Although the most advanced candidate malaria vaccine (RTS,S) has shown promise in clinical trials, its modest efficacy and durability have created uncertainty about the impact of RTS,S immunization (when used alone) on global malaria transmission. Here we describe the development and characterization of a novel modified vaccinia virus Ankara (MVA)–based malaria vaccine which co-expresses the Plasmodium yoelii circumsporozoite protein (CSP) and IL-15. Vaccination/challenge studies showed that C57BL/6 mice immunized with the MVA-CSP/IL15 vaccine were protected significantly better against a P. yoelii 17XNL sporozoite challenge than either mice immunized with an MVA vaccine expressing only CSP or naïve controls. Importantly, the levels of total anti-CSP IgG were elevated about 100-fold for the MVA-CSP/IL15 immunized group compared to mice immunized with the MVA-CSP construct that does not express IL-15. Among the IgG subtypes, the IL-15 expressing MVA-CSP vaccine induced levels of IgG1 (8 fold) and IgG2b (80 fold) higher than the MVA-CSP construct. The significantly enhanced humoral responses and protection detected after immunization with the MVA-CSP/IL15 vaccine suggest that this IL-15 expressing MVA construct could be considered in the development of future malaria immunization strategies.
Collapse
Affiliation(s)
- Marcela Parra
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Xia Liu
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Steven C. Derrick
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Amy Yang
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Alvaro Molina-Cruz
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD, 20852, United States of America
| | - Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD, 20852, United States of America
| | - Hong Zheng
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Phuong Thao Pham
- Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Martha Sedegah
- Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Arnel Belmonte
- Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Dianne D. Litilit
- Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Thomas A. Waldmann
- National Cancer Institute, Bethesda, MD, 20892, United States of America
| | - Sanjai Kumar
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Sheldon L. Morris
- Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, 20993, United States of America
| | - Liyanage P. Perera
- National Cancer Institute, Bethesda, MD, 20892, United States of America
- * E-mail:
| |
Collapse
|
27
|
Bijker EM, Borrmann S, Kappe SH, Mordmüller B, Sack BK, Khan SM. Novel approaches to whole sporozoite vaccination against malaria. Vaccine 2015; 33:7462-8. [PMID: 26469716 PMCID: PMC6858867 DOI: 10.1016/j.vaccine.2015.09.095] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 08/22/2015] [Accepted: 09/22/2015] [Indexed: 12/15/2022]
Abstract
The parasitic disease malaria threatens more than 3 billion people worldwide, resulting in more than 200 million clinical cases and almost 600,000 deaths annually. Vaccines remain crucial for prevention and ultimately eradication of infectious diseases and, for malaria, whole sporozoite based immunization has been shown to be the most effective in experimental settings. In addition to immunization with radiation-attenuated sporozoites, chemoprophylaxis and sporozoites (CPS) is a highly efficient strategy to induce sterile protection in humans. Genetically attenuated parasites (GAP) have demonstrated significant protection in rodent studies, and are now being advanced into clinical testing. This review describes the existing pre-clinical and clinical data on CPS and GAP, discusses recent developments and examines how to transform these immunization approaches into vaccine candidates for clinical development.
Collapse
Affiliation(s)
- Else M Bijker
- Radboud University Medical Center, Department of Medical Microbiology, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany; German Centre for Infection Research, University of Tübingen, Tübingen, Germany; Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Stefan H Kappe
- Seattle Biomedical Research Institute, Seattle, WA, USA; Department of Global Health, University of Washington, Seattle, WA, USA
| | - Benjamin Mordmüller
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany; German Centre for Infection Research, University of Tübingen, Tübingen, Germany; Centre de Recherches Médicales de Lambaréné, Alberts Schweitzer Hospital, BP 118 Lambaréné, Gabon
| | | | - Shahid M Khan
- Leiden University Medical Center, Department of Parasitology, PO Box 9600, 2300 RC Leiden, The Netherlands
| |
Collapse
|
28
|
McLEAN ARD, ATAIDE R, SIMPSON JA, BEESON JG, FOWKES FJI. Malaria and immunity during pregnancy and postpartum: a tale of two species. Parasitology 2015; 142:999-1015. [PMID: 25731914 PMCID: PMC4453920 DOI: 10.1017/s0031182015000074] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 12/19/2014] [Accepted: 01/16/2015] [Indexed: 11/07/2022]
Abstract
It is well established that pregnant women are at an increased risk of Plasmodium falciparum infection when compared to non-pregnant individuals and limited epidemiological data suggest Plasmodium vivax risk also increases with pregnancy. The risk of P. falciparum declines with successive pregnancies due to the acquisition of immunity to pregnancy-specific P. falciparum variants. However, despite similar declines in P. vivax risk with successive pregnancies, there is a paucity of evidence P. vivax-specific immunity. Cross-species immunity, as well as immunological and physiological changes that occur during pregnancy may influence the susceptibility to both P. vivax and P. falciparum. The period following delivery, the postpartum period, is relatively understudied and available epidemiological data suggests that it may also be a period of increased risk of infection to Plasmodium spp. Here we review the literature and directly compare and contrast the epidemiology, clinical pathogenesis and immunological features of P. vivax and P. falciparum in pregnancy, with a particular focus on studies performed in areas co-endemic for both species. Furthermore, we review the intriguing epidemiology literature of both P. falciparum and P. vivax postpartum and relate observations to the growing literature pertaining to malaria immunology in the postpartum period.
Collapse
Affiliation(s)
- A. R. D. McLEAN
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - R. ATAIDE
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
| | - J. A. SIMPSON
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - J. G. BEESON
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - F. J. I. FOWKES
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Epidemiology and Preventive Medicine and Department of Infectious Diseases, Monash University, Commercial Road, Melbourne, Victoria 3004, Australia
| |
Collapse
|
29
|
Sack BK, Keitany GJ, Vaughan AM, Miller JL, Wang R, Kappe SHI. Mechanisms of stage-transcending protection following immunization of mice with late liver stage-arresting genetically attenuated malaria parasites. PLoS Pathog 2015; 11:e1004855. [PMID: 25974076 PMCID: PMC4431720 DOI: 10.1371/journal.ppat.1004855] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 04/06/2015] [Indexed: 11/19/2022] Open
Abstract
Malaria, caused by Plasmodium parasite infection, continues to be one of the leading causes of worldwide morbidity and mortality. Development of an effective vaccine has been encumbered by the complex life cycle of the parasite that has distinct pre-erythrocytic and erythrocytic stages of infection in the mammalian host. Historically, malaria vaccine development efforts have targeted each stage in isolation. An ideal vaccine, however, would target multiple life cycle stages with multiple arms of the immune system and be capable of eliminating initial infection in the liver, the subsequent blood stage infection, and would prevent further parasite transmission. We have previously shown that immunization of mice with Plasmodium yoelii genetically attenuated parasites (GAP) that arrest late in liver stage development elicits stage-transcending protection against both a sporozoite challenge and a direct blood stage challenge. Here, we show that this immunization strategy engenders both T- and B-cell responses that are essential for stage-transcending protection, but the relative importance of each is determined by the host genetic background. Furthermore, potent anti-blood stage antibodies elicited after GAP immunization rely heavily on FC-mediated functions including complement fixation and FC receptor binding. These protective antibodies recognize the merozoite surface but do not appear to recognize the immunodominant merozoite surface protein-1. The antigen(s) targeted by stage-transcending immunity are present in both the late liver stages and blood stage parasites. The data clearly show that GAP-engendered protective immune responses can target shared antigens of pre-erythrocytic and erythrocytic parasite life cycle stages. As such, this model constitutes a powerful tool to identify novel, protective and stage-transcending T and B cell targets for incorporation into a multi-stage subunit vaccine.
Collapse
Affiliation(s)
- Brandon K. Sack
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Gladys J. Keitany
- Department of Immunology, University of Washington, Seattle, Washington, United States of America
| | - Ashley M. Vaughan
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Jessica L. Miller
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Ruobing Wang
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Stefan H. I. Kappe
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
- * E-mail:
| |
Collapse
|
30
|
Abstract
The development of a highly effective malaria vaccine remains a key goal to aid in the control and eventual eradication of this devastating parasitic disease. The field has made huge strides in recent years, with the first-generation vaccine RTS,S showing modest efficacy in a Phase III clinical trial. The updated 2030 Malaria Vaccine Technology Roadmap calls for a second generation vaccine to achieve 75% efficacy over two years for both Plasmodium falciparum and Plasmodium vivax, and for a vaccine that can prevent malaria transmission. Whole-parasite immunisation approaches and combinations of pre-erythrocytic subunit vaccines are now reporting high-level efficacy, whilst exciting new approaches to the development of blood-stage and transmission-blocking vaccine subunit components are entering clinical development. The development of a highly effective multi-component multi-stage subunit vaccine now appears to be a realistic ambition. This review will cover these recent developments in malaria vaccinology.
Collapse
|