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

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

Science Advances ◽

10.1126/sciadv.aba5068 ◽

2020 ◽

Vol 6 (32) ◽

pp. eaba5068 ◽

Cited By ~ 1

Author(s):

Kate Luisi ◽

Kaitlyn M. Morabito ◽

Katherine E. Burgomaster ◽

Mayuri Sharma ◽

Wing-Pui Kong ◽

...

Keyword(s):

Zika Virus ◽

Messenger Rna ◽

Protective Immunity ◽

Nonhuman Primates ◽

Neutralizing Antibody ◽

Effective Vaccine ◽

Proof Of Concept ◽

Zikv Infection ◽

Vaccine Candidates ◽

Rapid Responses

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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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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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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Protective efficacy of rhesus adenovirus COVID-19 vaccines against mouse-adapted SARS-CoV-2

Journal of Virology ◽

10.1128/jvi.00974-21 ◽

2021 ◽

Author(s):

Lisa H. Tostanoski ◽

Lisa E. Gralinski ◽

David R. Martinez ◽

Alexandra Schaefer ◽

Shant H. Mahrokhian ◽

...

Keyword(s):

Viral Replication ◽

Protective Efficacy ◽

Neutralizing Antibody ◽

Wild Type ◽

Adenovirus Serotype ◽

Vaccine Candidates ◽

Correlates Of Protection ◽

Immune Correlates ◽

Antibody Titers ◽

Adenovirus Vectors

The global COVID-19 pandemic has sparked intense interest in the rapid development of vaccines as well as animal models to evaluate vaccine candidates and to define immune correlates of protection. We recently reported a mouse-adapted SARS-CoV-2 virus strain (MA10) with the potential to infect wild-type laboratory mice, driving high levels of viral replication in respiratory tract tissues as well as severe clinical and respiratory symptoms, aspects of COVID-19 disease in humans that are important to capture in model systems. We evaluated the immunogenicity and protective efficacy of novel rhesus adenovirus serotype 52 (RhAd52) vaccines against MA10 challenge in mice. Baseline seroprevalence is lower for rhesus adenovirus vectors than for human or chimpanzee adenovirus vectors, making these vectors attractive candidates for vaccine development. We observed that RhAd52 vaccines elicited robust binding and neutralizing antibody titers, which inversely correlated with viral replication after challenge. These data support the development of RhAd52 vaccines and the use of the MA10 challenge virus to screen novel vaccine candidates and to study the immunologic mechanisms that underscore protection from SARS-CoV-2 challenge in wild-type mice. Importance We have developed a series of SARS-CoV-2 vaccines using rhesus adenovirus serotype 52 (RhAd52) vectors, which exhibits a lower seroprevalence than human and chimpanzee vectors, supporting their development as novel vaccine vectors or as an alternative Ad vector for boosting. We sought to test these vaccines using a recently reported mouse-adapted SARS-CoV-2 (MA10) virus to i) evaluate the protective efficacy of RhAd52 vaccines and ii) further characterize this mouse-adapted challenge model and probe immune correlates of protection. We demonstrate RhAd52 vaccines elicit robust SARS-CoV-2-specific antibody responses and protect against clinical disease and viral replication in the lungs. Further, binding and neutralizing antibody titers correlated with protective efficacy. These data validate the MA10 mouse model as a useful tool to screen and study novel vaccine candidates, as well as the development of RhAd52 vaccines for COVID-19.

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Host-Directed Antivirals: a Realistic Alternative to Fight Zika Virus

10.20944/preprints201807.0359.v1 ◽

2018 ◽

Author(s):

Juan-Carlos Saiz ◽

Nereida Jiménez de Oya ◽

Ana-Belén Blázquez ◽

Estela Escribano-Romero ◽

Miguel A. Martín-Acebes

Keyword(s):

Global Health ◽

Antiviral Activity ◽

Zika Virus ◽

Current Knowledge ◽

Structural Proteins ◽

Great Effort ◽

Zikv Infection ◽

Rapid Spread ◽

Viral Components ◽

Specific Antiviral Therapy

Zika virus (ZIKV), a mosquito-borne flavivirus, was an almost neglected pathogen until its introduction in the Americas in 2015, where it has been responsible for a threat to global health, causing a great social and sanitary alarm due to its increased virulence, rapid spread, and an association with severe neurological and ophthalmological complications. Currently, no specific antiviral therapy against ZIKV is available, and treatments are palliative and mainly directed to symptoms relief, such as fever and rash, by administering antipyretics, anti-histamines, and fluids for dehydration. Nevertheless, lately, a great effort has been made to search for antiviral candidates using different approaches and methodologies, ranging from repurposing of specific compounds with known antiviral activity to the screening of libraries and of natural compounds. The identified antiviral candidates include drugs targeting viral components (structural proteins and enzymes), as well as cellular ones. Here, we present an updated review of current knowledge about anti-ZIKV strategies, focusing on host-directed antivirals as a realistic alternative to combat ZIKV infection.

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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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Network of Interactions between ZIKA Virus Non-structural Proteins and Human Host Proteins

10.20944/preprints201909.0078.v1 ◽

2019 ◽

Author(s):

Volha A. Golubeva ◽

Thales C. Nepomuceno ◽

Giuliana de Gregoriis ◽

Rafael D. Mesquita ◽

Xueli Li ◽

...

Keyword(s):

Zika Virus ◽

Neural Progenitor Cells ◽

Affinity Purification ◽

Genetic Disorders ◽

Interaction Network ◽

Human Interaction ◽

Structural Proteins ◽

Infected Mosquito ◽

Zikv Infection ◽

Human Proteins

The Zika virus (ZIKV) is a mosquito-borne Flavivirus and can be transmitted through an infected mosquito bite or through human-to-human interaction by sexual activity, blood transfusion, breastfeeding or perinatal exposure. After the 2015-2016 outbreak in Brazil, a strong link between ZIKV infection and microcephaly emerged. ZIKV specifically targets human neural progenitor cells, suggesting that proteins encoded by ZIKV bind and inactivate host cell proteins leading to microcephaly. Here, we present a systematic annotation of interactions between human proteins and the seven non-structural ZIKV proteins corresponding to a Brazilian isolate. The interaction network was generated by combining tandem-affinity purification followed by mass spectrometry with yeast two-hybrid screens. We identified 150 human proteins, involved in distinct biological processes, as interactors to ZIKV non-structural proteins. Our interacting network is composed of proteins that have been previously associated with microcephaly in human genetic disorders and/or animal models. This study builds on previously published interacting networks of ZIKV and genes related to autosomal recessive primary microcephaly to generate a catalog of human cellular targets of ZIKV proteins implicated in processes related to microcephaly in humans. Collectively, this data can be used as a resource for future characterization of ZIKV infection biology and help create a basis for the discovery of drugs which may disrupt the interaction and reduce the health damage to the fetus.

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Host-Directed Antivirals: A Realistic Alternative to Fight Zika Virus

Viruses ◽

10.3390/v10090453 ◽

2018 ◽

Vol 10 (9) ◽

pp. 453 ◽

Cited By ~ 20

Author(s):

Juan-Carlos Saiz ◽

Nereida Oya ◽

Ana-Belén Blázquez ◽

Estela Escribano-Romero ◽

Miguel Martín-Acebes

Keyword(s):

Global Health ◽

Antiviral Activity ◽

Zika Virus ◽

Current Knowledge ◽

Structural Proteins ◽

Zikv Infection ◽

Rapid Spread ◽

Different Sources ◽

Specific Antiviral Therapy ◽

Do So

Zika virus (ZIKV), a mosquito-borne flavivirus, was an almost neglected pathogen until its introduction in the Americas in 2015, where it has been responsible for a threat to global health, causing a great social and sanitary alarm due to its increased virulence, rapid spread, and an association with severe neurological and ophthalmological complications. Currently, no specific antiviral therapy against ZIKV is available, and treatments are palliative and mainly directed toward the relief of symptoms, such as fever and rash, by administering antipyretics, anti-histamines, and fluids for dehydration. Nevertheless, lately, search for antivirals has been a major aim in ZIKV investigations. To do so, screening of libraries from different sources, testing of natural compounds, and repurposing of drugs with known antiviral activity have allowed the identification of several antiviral candidates directed to both viral (structural proteins and enzymes) and cellular elements. Here, we present an updated review of current knowledge about anti-ZIKV strategies, focusing on host-directed antivirals as a realistic alternative to combat ZIKV infection.

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Molecularly barcoded Zika virus libraries to probe in vivo evolutionary dynamics

10.1101/221564 ◽

2017 ◽

Author(s):

Matthew T. Aliota ◽

Dawn M. Dudley ◽

Christina M. Newman ◽

James Weger-Lucarelli ◽

Laurel M. Stewart ◽

...

Keyword(s):

Immune Evasion ◽

Zika Virus ◽

Nonhuman Primates ◽

Evolutionary Dynamics ◽

Complex Dynamics ◽

Virus Population ◽

Zikv Infection ◽

Infection Transmission ◽

Mosquito Infection

AbstractDefining the complex dynamics of Zika virus (ZIKV) infection in pregnancy and during transmission between vertebrate hosts and mosquito vectors is critical for a thorough understanding of viral transmission, pathogenesis, immune evasion, and potential reservoir establishment. Within-host viral diversity in ZIKV infection is low, which makes it difficult to evaluate infection dynamics. To overcome this biological hurdle, we constructed a molecularly barcoded ZIKV. This virus stock consists of a “synthetic swarm” whose members are genetically identical except for a run of eight consecutive degenerate codons, which creates approximately 64,000 theoretical nucleotide combinations that all encode the same amino acids. Deep sequencing this region of the ZIKV genome enables counting of individual barcode clonotypes to quantify the number and relative proportions of viral lineages present within a host. Here we used these molecularly barcoded ZIKV variants to study the dynamics of ZIKV infection in pregnant and non-pregnant macaques as well as during mosquito infection/transmission. The barcoded virus had no discernible fitness defects in vivo, and the proportions of individual barcoded virus templates remained stable throughout the duration of acute plasma viremia. ZIKV RNA also was detected in maternal plasma from a pregnant animal infected with barcoded virus for 64 days. The complexity of the virus population declined precipitously 8 days following infection of the dam, consistent with the timing of typical resolution of ZIKV in non-pregnant macaques, and remained low for the subsequent duration of viremia. Our approach showed that synthetic swarm viruses can be used to probe the composition of ZIKV populations over time in vivo to understand vertical transmission, persistent reservoirs, bottlenecks, and evolutionary dynamics.Author summaryUnderstanding the complex dynamics of Zika virus (ZIKV) infection during pregnancy and during transmission to and from vertebrate host and mosquito vector is critical for a thorough understanding of viral transmission, pathogenesis, immune evasion, and reservoir establishment. We sought to develop a virus model system for use in nonhuman primates and mosquitoes that allows for the genetic discrimination of molecularly cloned viruses. This “synthetic swarm” of viruses incorporates a molecular barcode that allows for tracking and monitoring individual viral lineages during infection. Here we infected rhesus macaques with this virus to study the dynamics of ZIKV infection in nonhuman primates as well as during mosquito infection/transmission. We found that the proportions of individual barcoded viruses remained relatively stable during acute infection in pregnant and nonpregnant animals. However, in a pregnant animal, the complexity of the virus population declined precipitously 8 days following infection, consistent with the timing of typical resolution of ZIKV in non-pregnant macaques, and remained low for the subsequent duration of viremia.

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