Development of a potent Zika virus vaccine using self-amplifying messenger RNA

Zika virus (ZIKV) is the cause of a pandemic associated with microcephaly in newborns and Guillain-Barre syndrome in adults. Currently, there are no available treatments or vaccines for ZIKV, and the development of a safe and effective vaccine is a high priority for many global health organizations. We describe the development of ZIKV vaccine candidates using the self-amplifying messenger RNA (SAM) platform technology delivered by cationic nanoemulsion (CNE) that allows bedside mixing and is particularly useful for rapid responses to pandemic outbreaks. Two immunizations of either of the two lead SAM (CNE) vaccine candidates elicited potent neutralizing antibody responses to ZIKV in mice and nonhuman primates. Both SAM (CNE) vaccines protected these animals from ZIKV challenge, with one candidate providing complete protection against ZIKV infection in nonhuman primates. The data provide a preclinical proof of concept that a SAM (CNE) vaccine candidate can rapidly elicit protective immunity against ZIKV.

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Distinct neutralizing antibody correlates of protection among related Zika virus vaccines identify a role for antibody quality

Science Translational Medicine ◽

10.1126/scitranslmed.aaw9066 ◽

2020 ◽

Vol 12 (547) ◽

pp. eaaw9066

Author(s):

Sonia Maciejewski ◽

Tracy J. Ruckwardt ◽

Kaitlyn M. Morabito ◽

Bryant M. Foreman ◽

Katherine E. Burgomaster ◽

...

Keyword(s):

Zika Virus ◽

Nonhuman Primates ◽

Neutralizing Antibody ◽

Structural Proteins ◽

Zikv Infection ◽

Vaccine Candidates ◽

Correlates Of Protection ◽

Vaccine Antigens ◽

Maturation State ◽

Induced Immunity

The emergence of Zika virus (ZIKV) in the Americas stimulated the development of multiple ZIKV vaccine candidates. We previously developed two related DNA vaccine candidates encoding ZIKV structural proteins that were immunogenic in animal models and humans. We sought to identify neutralizing antibody (NAb) properties induced by each vaccine that correlated with protection in nonhuman primates (NHPs). Despite eliciting equivalent NAb titers in NHPs, these vaccines were not equally protective. The transfer of equivalent titers of vaccine-elicited NAb into AG129 mice also revealed nonequivalent protection, indicating qualitative differences among antibodies (Abs) elicited by these vaccines. Both vaccines elicited Abs with similar binding titers against envelope protein monomers and those incorporated into virus-like particles, as well as a comparable capacity to orchestrate phagocytosis. Functional analysis of vaccine-elicited NAbs from NHPs and humans revealed a capacity to neutralize the structurally mature form of the ZIKV virion that varied in magnitude among vaccine candidates. Conversely, sensitivity to the virion maturation state was not a characteristic of NAbs induced by natural or experimental infection. Passive transfer experiments in mice revealed that neutralization of mature ZIKV virions more accurately predicts protection from ZIKV infection. These findings demonstrate that NAb correlates of protection may differ among vaccine antigens when assayed using standard neutralization platforms and suggest that measurements of Ab quality, including the capacity to neutralize mature virions, will be critical for defining correlates of ZIKV vaccine-induced immunity.

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Maternal vaccination and protective immunity against Zika virus vertical transmission

Nature Communications ◽

10.1038/s41467-019-13589-1 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 9

Author(s):

Chao Shan ◽

Xuping Xie ◽

Huanle Luo ◽

Antonio E. Muruato ◽

Yang Liu ◽

...

Keyword(s):

Zika Virus ◽

Protective Immunity ◽

Neutralizing Antibody ◽

In Utero ◽

Pregnant Mouse ◽

T Cell Response ◽

Zikv Infection ◽

Maternal Immunization ◽

Maternal Vaccination ◽

Pregnant Mice

AbstractAn important goal of the Zika virus (ZIKV) vaccine is to prevent a congenital syndrome in fetuses of pregnant women, but studies directly evaluating maternal vaccination for ZIKV are lacking. Here we report maternal vaccination using a live-attenuated ZIKV vaccine (3ʹUTR-∆10-LAV) in a pregnant mouse model. Maternal immunization with 3ʹUTR-∆10-LAV does not cause any adverse effects on pregnancy, fetal development, or offspring behavior. One maternal immunization fully protects dams against ZIKV infection and in utero transmission. Although neutralizing antibody alone is sufficient to prevent in utero transmission, a higher neutralizing titer is required to protect pregnant mice against in utero transmission than that required to protect non-pregnant mice against viral infection. The immunized dams transfer maternal antibodies to pups, which protect neonates against ZIKV infection. Notably, pregnancy weakens maternal T cell response to 3ʹUTR-∆10-LAV vaccination. Our results suggest that, besides vaccinating non-pregnant individuals, 3ʹUTR-∆10-LAV may also be considered for maternal vaccination.

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A Chimeric Zika Virus between Viral Strains MR766 and BeH819015 Highlights a Role for E-glycan Loop in Antibody-mediated Virus Neutralization

Vaccines ◽

10.3390/vaccines7020055 ◽

2019 ◽

Vol 7 (2) ◽

pp. 55 ◽

Cited By ~ 10

Author(s):

Etienne Frumence ◽

Wildriss Viranaicken ◽

Sandra Bos ◽

Maria-Teresa Alvarez-Martinez ◽

Marjolaine Roche ◽

...

Keyword(s):

Zika Virus ◽

Protective Immunity ◽

Neutralizing Antibody ◽

Health Concern ◽

Zikv Infection ◽

Humoral Immune ◽

African Strain ◽

Antibody Titers ◽

Antibody Epitopes ◽

Viral Clone

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus which is of major public health concern. ZIKV infection is recognized as the cause of congenital Zika disease and other neurological defects, with no specific prophylactic or therapeutic treatments. As the humoral immune response is an essential component of protective immunity, there is an urgent need for effective vaccines that confer protection against ZIKV infection. In the present study, we evaluate the immunogenicity of chimeric viral clone ZIKBeHMR-2, in which the region encoding the structural proteins of the African strain MR766 backbone was replaced with its counterpart from the epidemic strain BeH819015. Three amino-acid substitutions I152T, T156I, and H158Y were introduced in the glycan loop of the E protein (E-GL) making ZIKBeHMR-2 a non-glycosylated virus. Adult BALB/c mice inoculated intraperitoneally with ZIKBeHMR-2 developed anti-ZIKV antibodies directed against viral proteins E and NS1 and a booster dose increased antibody titers. Immunization with ZIKBeHMR-2 resulted in a rapid production of neutralizing anti-ZIKV antibodies. Antibody-mediated ZIKV neutralization was effective against viral strain MR766, whereas epidemic ZIKV strains were poorly sensitive to neutralization by anti-ZIKBeHMR-2 immune sera. From our data, we propose that the three E-GL residues at positions E-152, E-156, and E-158 greatly influence the accessibility of neutralizing antibody epitopes on ZIKV.

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A Whole Virion Vaccine for COVID-19 Produced via a Novel Inactivation Method and Preliminary Demonstration of Efficacy in an Animal Challenge Model

Vaccines ◽

10.3390/vaccines9040340 ◽

2021 ◽

Vol 9 (4) ◽

pp. 340

Author(s):

Izabela K Ragan ◽

Lindsay M Hartson ◽

Taru S Dutt ◽

Andres Obregon-Henao ◽

Rachel M Maison ◽

...

Keyword(s):

Vaccine Candidate ◽

Rapid Development ◽

Neutralizing Antibody ◽

Emerging Diseases ◽

Effective Vaccine ◽

Preliminary Evaluation ◽

Sequencing Data ◽

Post Challenge ◽

Vaccine Candidates ◽

The Impact

The COVID-19 pandemic has generated intense interest in the rapid development and evaluation of vaccine candidates for this disease and other emerging diseases. Several novel methods for preparing vaccine candidates are currently undergoing clinical evaluation in response to the urgent need to prevent the spread of COVID-19. In many cases, these methods rely on new approaches for vaccine production and immune stimulation. We report on the use of a novel method (SolaVAX) for production of an inactivated vaccine candidate and the testing of that candidate in a hamster animal model for its ability to prevent infection upon challenge with SARS-CoV-2 virus. The studies employed in this work included an evaluation of the levels of neutralizing antibody produced post-vaccination, levels of specific antibody sub-types to RBD and spike protein that were generated, evaluation of viral shedding post-challenge, flow cytometric and single cell sequencing data on cellular fractions and histopathological evaluation of tissues post-challenge. The results from this preliminary evaluation provide insight into the immunological responses occurring as a result of vaccination with the proposed vaccine candidate and the impact that adjuvant formulations, specifically developed to promote Th1 type immune responses, have on vaccine efficacy and protection against infection following challenge with live SARS-CoV-2. This data may have utility in the development of effective vaccine candidates broadly. Furthermore, the results of this preliminary evaluation suggest that preparation of a whole virion vaccine for COVID-19 using this specific photochemical method may have potential utility in the preparation of one such vaccine candidate.

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Immunization with RBD-P2 and N protects against SARS-CoV-2 in nonhuman primates

Science Advances ◽

10.1126/sciadv.abg7156 ◽

2021 ◽

Vol 7 (22) ◽

pp. eabg7156

Author(s):

So-Hee Hong ◽

Hanseul Oh ◽

Yong Wook Park ◽

Hye Won Kwak ◽

Eun Young Oh ◽

...

Keyword(s):

Nucleocapsid Protein ◽

Nonhuman Primates ◽

Vaccine Candidate ◽

Statistical Significance ◽

Neutralizing Antibody ◽

Spike Protein ◽

Vaccine Candidates ◽

Cell Responses ◽

Antibody Levels ◽

Further Development

Since the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), various vaccines are being developed, with most vaccine candidates focusing on the viral spike protein. Here, we developed a previously unknown subunit vaccine comprising the receptor binding domain (RBD) of the spike protein fused with the tetanus toxoid epitope P2 (RBD-P2) and tested its efficacy in rodents and nonhuman primates (NHPs). We also investigated whether the SARS-CoV-2 nucleocapsid protein (N) could increase vaccine efficacy. Immunization with N and RBD-P2 (RBDP2/N) + alum increased T cell responses in mice and neutralizing antibody levels in rats compared with those obtained using RBD-P2 + alum. Furthermore, in NHPs, RBD-P2/N + alum induced slightly faster SARS-CoV-2 clearance than that induced by RBD-P2 + alum, albeit without statistical significance. Our study supports further development of RBD-P2 as a vaccine candidate against SARS-CoV-2. Also, it provides insights regarding the use of N in protein-based vaccines against SARS-CoV-2.

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Current Status of Zika Virus Vaccines: Successes and Challenges

Vaccines ◽

10.3390/vaccines8020266 ◽

2020 ◽

Vol 8 (2) ◽

pp. 266 ◽

Cited By ~ 6

Author(s):

Aryamav Pattnaik ◽

Bikash R. Sahoo ◽

Asit K. Pattnaik

Keyword(s):

Zika Virus ◽

Viral Infections ◽

Current Status ◽

Effective Vaccine ◽

Congenital Diseases ◽

Vaccine Candidates ◽

Efficacy Trials ◽

Nucleic Acid Vaccines ◽

Funding Agencies ◽

Inactivated Vaccines

The recently emerged Zika virus (ZIKV) spread to the Americas, causing a spectrum of congenital diseases including microcephaly in newborn and Guillain-Barré syndrome (GBS) in adults. The unprecedented nature of the epidemic and serious diseases associated with the viral infections prompted the global research community to understand the immunopathogenic mechanisms of the virus and rapidly develop safe and efficacious vaccines. This has led to a number of ZIKV vaccine candidates that have shown significant promise in human clinical trials. These candidates include nucleic acid vaccines, inactivated vaccines, viral-vectored vaccines, and attenuated vaccines. Additionally, a number of vaccine candidates have been shown to protect animals in preclinical studies. However, as the epidemic has waned in the last three years, further development of the most promising vaccine candidates faces challenges in clinical efficacy trials, which is needed before a vaccine is brought to licensure. It is important that a coalition of government funding agencies and private sector companies is established to move forward with a safe and effective vaccine ready for deployment when the next ZIKV epidemic occurs.

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Distinct cellular immune signatures in acute Zika virus infection are associated with high or low persisting neutralizing antibody titers

10.1101/2021.05.27.446054 ◽

2021 ◽

Author(s):

Elizabeth E. McCarthy ◽

Pamela M. Odorizzi ◽

Emma Lutz ◽

Carolyn P. Smullin ◽

Iliana Tenvooren ◽

...

Keyword(s):

Zika Virus ◽

Neutralizing Antibodies ◽

Viral Infections ◽

Immune Cell ◽

Acute Infection ◽

Neutralizing Antibody ◽

Natural Immunity ◽

Zikv Infection ◽

Antibody Titers ◽

Cellular Immune

Although the formation of a durable neutralizing antibody response after an acute viral infection is a key component of protective immunity, little is known about why some individuals generate high versus low neutralizing antibody titers to infection or vaccination. Infection with Zika virus (ZIKV) during pregnancy can cause devastating fetal outcomes, and efforts to understand natural immunity to this infection are essential for optimizing vaccine design. In this study, we leveraged the high-dimensional single-cell profiling capacity of mass cytometry (CyTOF) to deeply characterize the cellular immune response to acute and convalescent ZIKV infection in a cohort of blood donors in Puerto Rico incidentally found to be viremic during the 2015-2016 epidemic in the Americas. During acute ZIKV infection, we identified widely coordinated responses across innate and adaptive immune cell lineages. High frequencies of multiple activated innate immune subsets, as well as activated follicular helper CD4+ T cells and proliferating CD27-IgD- B cells, during acute infection were associated with high titers of ZIKV neutralizing antibodies at 6 months post-infection. On the other hand, low titers of ZIKV neutralizing antibodies were associated with immune features that suggested a cytotoxic-skewed immune "set-point." Our study offers insight into the cellular coordination of immune responses and identifies candidate cellular biomarkers that may offer predictive value in vaccine efficacy trials for ZIKV and other acute viral infections aimed at inducing high titers of neutralizing antibodies.

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Zika virus is transmitted in neural progenitor cells via cell-to-cell spread and infection is inhibited by the autophagy inducer trehalose

Journal of Virology ◽

10.1128/jvi.02024-20 ◽

2020 ◽

pp. JVI.02024-20

Author(s):

Alex E Clark ◽

Zhe Zhu ◽

Florian Krach ◽

Jeremy N Rich ◽

Gene W. Yeo ◽

...

Keyword(s):

Viral Replication ◽

Progenitor Cells ◽

Zika Virus ◽

Neural Progenitor Cells ◽

Neutralizing Antibody ◽

Neural Progenitor ◽

Health Concern ◽

Free Virus ◽

Zikv Infection ◽

Infected Cells

Zika virus (ZIKV) is a mosquito-borne human pathogen that causes congenital Zika syndrome and neurological symptoms in some adults. There are currently no approved treatments or vaccines for ZIKV, and exploration of therapies targeting host processes could avoid viral development of drug resistance. The purpose of our study was to determine if the non-toxic and widely used disaccharide trehalose, which showed antiviral activity against Human Cytomegalovirus (HCMV) in our previous work, could restrict ZIKV infection in clinically relevant neural progenitor cells (NPCs). Trehalose is known to induce autophagy, the degradation and recycling of cellular components. Whether autophagy is proviral or antiviral for ZIKV is controversial and depends on cell type and specific conditions used to activate or inhibit autophagy. We show here that trehalose treatment of NPCs infected with recent ZIKV isolates from Panama and Puerto Rico significantly reduces viral replication and spread. In addition, we demonstrate that ZIKV infection in NPCs spreads primarily cell-to-cell as an expanding infectious center, and NPCs are infected via contact with infected cells far more efficiently than by cell-free virus. Importantly, ZIKV was able to spread in NPCs in the presence of neutralizing antibody.Importance Zika virus causes birth defects and can lead to neurological disease in adults. While infection rates are currently low, ZIKV remains a public health concern with no treatment or vaccine available. Targeting a cellular pathway to inhibit viral replication is a potential treatment strategy that avoids development of antiviral resistance. We demonstrate in this study that the non-toxic autophagy-inducing disaccharide trehalose reduces spread and output of ZIKV in infected neural progenitor cells (NPCs), the major cells infected in the fetus. We show that ZIKV spreads cell-to-cell in NPCs as an infectious center and that NPCs are more permissive to infection by contact with infected cells than by cell-free virus. We find that neutralizing antibody does not prevent the spread of the infection in NPCs. These results are significant in demonstrating anti-ZIKV activity of trehalose and in clarifying the primary means of Zika virus spread in clinically relevant target cells.

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Cross-Protection Against Zika Virus Infection Conferred by a Live Attenuated Japanese Encephalitis SA14-14-2 Vaccine

10.1101/2020.02.14.950352 ◽

2020 ◽

Cited By ~ 1

Author(s):

Ran Wang ◽

Zida Zhen ◽

Lance Turtle ◽

Baohua Hou ◽

Yueqi Li ◽

...

Keyword(s):

Japanese Encephalitis Virus ◽

Japanese Encephalitis ◽

Cellular Immunity ◽

Zika Virus ◽

T Cell Response ◽

Encephalitis Virus ◽

Cross Protection ◽

World Health ◽

Effective Vaccine ◽

Zikv Infection

AbstractZika virus (ZIKV) and Japanese encephalitis virus (JEV) are closely related mosquito-borne flaviviruses. Japanese encephalitis (JE) vaccine SA14-14-2 has been in the Chinese national Expanded Program on Immunization since 2007. The recent recognition of severe disease syndromes associated with ZIKV, and the identification of ZIKV from mosquitoes in China, prompts an urgent need to investigate the potential interaction between the two. In this study, we showed that SA14-14-2 is protective against ZIKV infection in mice. JE vaccine SA14-14-2 triggered both Th1 and Th2 cross-reactive immune responses to ZIKV; however, it was cellular immunity that predominantly mediated cross-protection against ZIKV infection. Passive transfer of immune sera did not result in significant cross-protection, but did mediate antibody dependent enhancement in vitro, though this did not have an adverse impact on survival. This study suggests that SA14-14-2 vaccine can protect against ZIKV through a cross-reactive T cell response. This is vital information in terms of ZIKV prevention or precaution in those ZIKV-affected regions where JEV circulates or SA14-14-2 is in widespread use, and opens a promising avenue into developing a novel bivalent vaccine against both ZIKV and JEV.ImportanceJapanese encephalitis is a controllable disease in many countries in Asia, especially in China, where many people have Japanese encephalitis virus (JEV) immunity due to extensive JEV vaccination campaigns or natural exposure. Live-attenuated SA14-14-2 strain is a safe and effective vaccine recommended by the World Health Organization and has been vaccinated more than 600 million doses since 1989. As the prevalence of Zika virus (ZIKV) and rising risk in above regions, the cross-reactive immune response between these two antigenically closely related flaviviruses, JEV and ZIKV, should also be fully recognized, which is presumed to be based on those ambiguous cross-reactive immunity between dengue virus and ZIKV. In this study, we found that JEV SA14-14-2 vaccine conferred cross-protection against ZIKV challenge in mice, which is mainly due to cellular immunity rather than neutralizing antibody response. However, specific protective components or cooperation between components warrant to be explored in subsequent experiments. In conclusion, this study can provide important evidence for those who live in JEV-endemic areas and are at risk for ZIKV infection.

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Current Progress in the Development of Zika Virus Vaccines

Vaccines ◽

10.3390/vaccines9091004 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1004

Author(s):

Kehui Zhou ◽

Chaoqun Li ◽

Wen Shi ◽

Xiaodan Hu ◽

Kutty Selva Nandakumar ◽

...

Keyword(s):

Zika Virus ◽

Large Scale ◽

Vaccine Development ◽

Clinical Symptoms ◽

Effective Vaccine ◽

Zikv Infection ◽

Teratogenic Effects ◽

Subunit Vaccines ◽

Live Attenuated Vaccines ◽

Inactivated Vaccines

Zika virus (ZIKV) is an arbovirus first discovered in the Americas. ZIKV infection is insidious based on its mild clinical symptoms observed after infection. In Brazil, after 2015, ZIKV infection broke out on a large scale, and many infected pregnant women gave birth to babies with microcephaly. The teratogenic effects of the virus on the fetus and its effects on nerves and the immune system have attracted great attention. Currently, no specific prophylactics or therapeutics are clinically available to treat ZIKV infection. Development of a safe and effective vaccine is essential to prevent the rise of any potential pandemic. In this review, we summarize the latest research on Zika vaccine development based on different strategies, including DNA vaccines, subunit vaccines, live-attenuated vaccines, virus-vector-based vaccines, inactivated vaccines, virus-like particles (VLPs), mRNA-based vaccines, and others. We anticipate that this review will facilitate further progress toward the development of effective and safe vaccines against ZIKV infection.

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