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14 result(s) for "Lemus, Nicholas"
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A Newcastle disease virus expressing a stabilized spike protein of SARS-CoV-2 induces protective immune responses
Rapid development of COVID-19 vaccines has helped mitigating SARS-CoV-2 spread, but more equitable allocation of vaccines is necessary to limit the global impact of the COVID-19 pandemic and the emergence of additional variants of concern. We have developed a COVID-19 vaccine candidate based on Newcastle disease virus (NDV) that can be manufactured at high yields in embryonated eggs. Here, we show that the NDV vector expressing an optimized spike antigen (NDV-HXP-S) is a versatile vaccine inducing protective antibody responses. NDV-HXP-S can be administered intramuscularly as inactivated vaccine or intranasally as live vaccine. We show that NDV-HXP-S GMP-produced in Vietnam, Thailand and Brazil is effective in the hamster model. Furthermore, we show that intramuscular vaccination with NDV-HXP-S reduces replication of tested variants of concerns in mice. The immunity conferred by NDV-HXP-S effectively counteracts SARS-CoV-2 infection in mice and hamsters. Here the authors show that a Newcastle disease virus based COVID-19 vaccine expressing a stabilized spike protein induces protective immunity in small animal models and reduces replication of variants of concerns. This vaccine candidate can be produced by influenza virus vaccine manufactures around the world.
Mucosal multivalent NDV-based vaccine provides cross-reactive immune responses against SARS-CoV-2 variants in animal models
A new generation of mucosal vaccine against the ever-evolving SARS-CoV-2 is of great value to fight COVID-19. In previous studies, our groups developed a viral vector vaccine based on an avirulent Newcastle disease virus (NDV) expressing the prefusion-stabilized spike protein of SARS-CoV-2 (NDV-HXP-S). Here we characterized the biodistribution and immunogenicity of a live mucosal NDV-HXP-S vaccine in animal models. NDV showed restricted replication in mice and hamsters. Despite limited replication, intranasal live NDV-HXP-S provided protection against SARS-CoV-2 challenge and direct-contact transmission in hamsters. Importantly, a trivalent live NDV-HXP-S vaccine (Wuhan, Beta, Delta) induced more cross-reactive antibody responses against the phylogenetically distant Omicron variant than the ancestral vaccine. Furthermore, intranasal trivalent live NDV-HXP-S boosted systemic and mucosal immunity in mice pre-immunized with mRNA vaccine. Overall, a mucosal multivalent live NDV-HXP-S vaccine shows great promise as a safe, next-generation vaccine conferring broad mucosal and systemic immunity against future SARS-CoV-2 variants.
Preclinical evaluation of a universal inactivated influenza B vaccine based on the mosaic hemagglutinin-approach
We have developed a new universal influenza B vaccination strategy based on inactivated influenza B viruses displaying mosaic hemagglutinins (mHAs). Recombinant mHA viruses were constructed by replacing the four major antigenic sites of influenza B virus HAs, with those from exotic avian influenza A virus HAs. Sequential vaccination of naïve mice with mHA-based vaccines elicited higher immune responses towards the immuno-subdominant conserved epitopes of the HA than vaccination with wildtype viruses. Among the different preparations tested, mHA split vaccines were less immunogenic than their whole inactivated virus counterparts. This lower immunogenicity was overcome by the combination with adjuvants. mHA split vaccines adjuvanted with a Toll-like receptor-9 agonist (CpG 1018) increased Th1 immunity and in vivo cross-protection, whereas adjuvanting with an MF59-like oil-in-water nano-emulsion (AddaVax) enhanced and broadened humoral immune responses and antibody-mediated cross-protection. The mHA vaccines with or without adjuvant were subsequently evaluated in mice that were previously immunized to closely mimic human pre-existing immunity to influenza B viruses and the contribution of innate and cellular immunity was evaluated in this model. We believe these preclinical studies using the mHA strategy represent a major step toward the evaluation of a universal influenza B virus vaccine in clinical trials.
Immunogenicity and efficacy of homologous and heterologous NDV and MVA SARS-CoV-2 vaccines in mice and hamsters
Effective vaccination strategies adaptable to emerging viruses like SARS-CoV-2 and capable of inducing robust protective immunity are needed. We evaluated the immunogenicity and protective efficacy of homologous and heterologous prime/boost regimens against SARS-CoV-2 in K18-hACE2 mice and Syrian hamsters using Newcastle disease virus (NDV-HXP-S, intranasal) and modified vaccinia virus Ankara (MVA-S(3P), intramuscular) vectors encoding a prefusion-stabilized SARS-CoV-2 spike (S) protein. All regimens protected against weight loss and markedly reduced viral replication and lung pathology. Vaccination induced serum anti-S and anti-receptor binding domain IgGs and neutralizing antibodies against ancestral virus and variants. In mice, mucosal anti-S IgA and IgG were detected after NDV-HXP-S immunization. Homologous MVA-S(3P)/MVA-S(3P) and heterologous NDV-HXP-S/MVA-S(3P) elicited higher polyfunctional systemic T-cell responses, while homologous NDV-HXP-S/NDV-HXP-S induced stronger pulmonary CD8 + T cells. Hamsters vaccinated with NDV-HXP-S exhibited protection of the upper respiratory tract, with the NDV-HXP-S/MVA-S(3P) regimen showing a trend toward reduced direct contact transmission of SARS-CoV-2. These findings demonstrate the capacity of NDV and MVA vector platforms to induce robust systemic and mucosal antigen-specific humoral and T-cell responses against SARS-CoV-2, contributing to protection against both disease and transmission, and support further exploration of these vector platforms for vaccination against SARS-CoV-2 and potentially other pathogens.
A single immunization with intranasal Newcastle disease virus (NDV)-based XBB.1.5 variant vaccine reduces disease and transmission in animals against matched-variant challenge
The rapid development of coronavirus disease 2019 (COVID-19) vaccines has helped mitigate the initial impact of the pandemic. However, in order to reduce transmission rates and protect more vulnerable and immunocompromised individuals unable to mount an effective immune response, development of a next-generation of mucosal vaccines is necessary. Here, we developed an intranasal Newcastle disease virus (NDV)-based vaccine expressing the spike of the XBB.1.5 variant stabilized in its pre-fusion conformation (NDV-HXP-S). We demonstrated that one or two intranasal immunizations with live NDV-HXP-S expressing the XBB.1.5 spike induces systemic and mucosal antibody responses in mice and protects them from a challenge with the XBB.1.5 variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Furthermore, one or two intranasal vaccinations with NDV-HXP-S XBB.1.5 protected hamsters from variant matched infection and reduced virus emission, thereby providing complete protection to naïve animals in a direct contact transmission study. The data shown in this study supports the notion that intranasal vaccination with variant-adapted NDV-HXP-S induces protective mucosal immunity and reduces transmission rates, highlighting the robust protective efficacy of a single mucosal vaccination in mice and hamsters. •An intranasal SARS-CoV-2 Newcastle disease virus (NDV)-based vaccine for the XBB.1.5 variant of concern was developed.•One or two immunizations induced mucosal and systemic antibodies in mice and hamsters•Serum antibodies neutralized XBB.1.5, EG.5.1, BA.2.86, JN.1 and KP.2 pseudotyped virus.•Vaccinated mice and hamsters were protected from a SARS-CoV-2 XB.1.5 challenge.•Vaccination reduced virus emission in hamsters, thereby completely protecting naïve animals in a transmission study.
The immunodominance of antigenic site Sb on the H1 influenza virus hemagglutinin increases with high immunoglobulin titers of the cohorts and with young age, but not sex
The head domain of the hemagglutinin of influenza viruses plays a dominant role in the antibody response due to the presence of immunodominant antigenic sites that are the main targets of host neutralizing antibodies. For the H1 hemagglutinin, five major antigenic sites defined as Sa, Sb, Ca1, Ca2, and Cb have been described. Although previous studies have focused on defining the hierarchy of the antigenic sites of the hemagglutinin in different human cohorts, it is still unclear if the immunodominance profile of the antigenic sites might change with the antibody levels of individuals or if other demographic factors (such as exposure history, sex, or age) could also influence the importance of the antigenic sites. The major antigenic sites of influenza viruses hemagglutinins are responsible for eliciting most of the hemagglutination inhibition antibodies in the host. To determine the antibody prevalence towards each major antigenic site, we evaluated the hemagglutination inhibition against a panel of mutant H1 viruses, each one lacking one of the “classic” antigenic sites. Our results showed that the individuals from the Stop Flu NYU cohort had an immunodominant response towards the sites Sb and Ca2 of H1 hemagglutinin. A simple logistic regression analysis of the immunodominance profiles and the hemagglutination inhibition titers displayed by each donor revealed that individuals with high hemagglutination inhibition titers against the wild-type influenza virus exhibited higher probabilities of displaying an immunodominance profile dominated by Sb, followed by Ca2 (Sb > Ca2 profile), while individuals with low hemagglutination inhibition titers presented a higher chance of displaying an immunodominance profile in which Sb and Ca2 presented the same level of immunodominance (Sb = Ca2 profile). Finally, while age exhibited an influence on the immunodominance of the antigenic sites, biological sex was not related to displaying a specific immunodominance profile.
Trivalent NDV-HXP-S vaccine protects against phylogenetically distant SARS-CoV-2 variants of concern in mice
Equitable access to vaccines is necessary to limit the global impact of the coronavirus disease 2019 (COVID-19) pandemic and the emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. In previous studies, we described the development of a low-cost vaccine based on a Newcastle Disease virus (NDV) expressing the prefusion stabilized spike protein from SARS-CoV-2, named NDV-HXP-S. Here, we present the development of next-generation NDV-HXP-S variant vaccines, which express the stabilized spike protein of the Beta, Gamma and Delta variants of concerns (VOC). Combinations of variant vaccines in bivalent, trivalent and tetravalent formulations were tested for immunogenicity and protection in mice. We show that the trivalent preparation, composed of the ancestral Wuhan, Beta and Delta vaccines, substantially increases the levels of protection and of cross-neutralizing antibodies against mismatched, phylogenetically distant variants, including the currently circulating Omicron variant.
Genome editing in the mouse brain with minimally immunogenic Cas9 RNPs
Transient delivery of CRISPR-Cas9 ribonucleoproteins (RNPs) into the central nervous system (CNS) for therapeutic genome editing could avoid limitations of viral vector-based delivery including cargo capacity, immunogenicity, and cost. Here we tested the ability of cell penetrant Cas9 RNPs to edit the mouse striatum when introduced using a convection enhanced delivery system. These transient Cas9 RNPs showed comparable editing of neurons and reduced adaptive immune responses relative to one formulation of Cas9 delivered using AAV serotype 9. The production of ultra-low-endotoxin Cas9 protein manufactured at scale further improved innate immunity. We conclude that injection-based delivery of minimally immunogenic CRISPR genome editing RNPs into the CNS provides a valuable alternative to virus-mediated genome editing.
A Newcastle disease virus-vector expressing a prefusion-stabilized spike protein of SARS-CoV-2 induces protective immune responses against prototype virus and variants of concern in mice and hamsters
Rapid development of coronavirus disease 2019 (COVID-19) vaccines and expedited authorization for use and approval has been proven beneficial to mitigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread and given hope in this desperate situation. It is believed that sufficient supplies and equitable allocations of vaccines are necessary to limit the global impact of the COVID-19 pandemic and the emergence of additional variants of concern. We have developed a COVID-19 vaccine based on Newcastle disease virus (NDV) that can be manufactured at high yields in embryonated eggs. Here we provide evidence that the NDV vector expressing an optimized spike antigen (NDV-HXP-S), upgraded from our previous construct, is a versatile vaccine that can be used live or inactivated to induce strong antibody responses and to also cross-neutralize variants of concern. The immunity conferred by NDV-HXP-S effectively counteracts SARS-CoV-2 infection in mice and hamsters. It is noteworthy that vaccine lots produced by existing egg-based influenza virus vaccine manufacturers in Vietnam, Thailand and Brazil exhibited excellent immunogenicity and efficacy in hamsters, demonstrating that NDV-HXP-S vaccines can be quickly produced at large-scale to meet global demands. Competing Interest Statement The Icahn School of Medicine at Mount Sinai has filed patent applications entitled RECOMBINANT NEWCASTLE DISEASE VIRUS EXPRESSING SARS-COV-2 SPIKE PROTEIN AND USES THEREOF which names PP, FK, WS and AG-S. as inventors. The AG-S laboratory has received research support from Pfizer, Senhwa Biosciences, Kenall Manufacturing, Avimex, Johnson & Johnson, Dynavax, 7Hills Pharma, Pharmamar, ImmunityBio, Accurius, Merck and Nanocomposix, and AG-S has consulting agreements for the following companies involving cash and/or stock: Vivaldi Biosciences, Contrafect, 7Hills Pharma, Avimex, Vaxalto, Pagoda, Accurius, Esperovax, Farmak, Applied Biological Laboratories and Pfizer.
MU variability in CBCT‐guided online adaptive radiation therapy
Purpose CBCT‐guided online‐adaptive radiotherapy (oART) systems have been made possible by using artificial intelligence and automation to substantially reduce treatment planning time during on‐couch adaptive sessions. Evaluating plans generated during an adaptive session presents significant challenges to the clinical team as the planning process gets compressed into a shorter window than offline planning. We identified MU variations up to 30% difference between the adaptive plan and the reference plan in several oART sessions that caused the clinical team to question the accuracy of the oART dose calculation. We investigated the cause of MU variation and the overall accuracy of the dose delivered when MU variations appear unnecessarily large. Methods Dosimetric and adaptive plan data from 604 adaptive sessions of 19 patients undergoing CBCT‐guided oART were collected. The analysis included total MU per fraction, planning target volume (PTV) and organs at risk (OAR) volumes, changes in PTV‐OAR overlap, and DVH curves. Sessions with MU greater than two standard deviations from the mean were reoptimized offline, verified by an independent calculation system, and measured using a detector array. Results MU variations relative to the reference plan were normally distributed with a mean of −1.0% and a standard deviation of 11.0%. No significant correlation was found between MU variation and anatomic changes. Offline reoptimization did not reliably reproduce either reference or on‐couch total MUs, suggesting that stochastic effects within the oART optimizer are likely causing the variations. Independent dose calculation and detector array measurements resulted in acceptable agreement with the planned dose. Conclusions MU variations observed between oART plans were not caused by any errors within the oART workflow. Providers should refrain from using MU variability as a way to express their confidence in the treatment planning accuracy. Clinical decisions during on‐couch adaptive sessions should rely on validated secondary dose calculations to ensure optimal plan selection.