A yeast expressed RBD-based SARS-CoV-2 vaccine formulated with 3M-052-alum adjuvant promotes protective efficacy in non-human primates

Ongoing SARS-CoV-2 vaccine development is focused on identifying stable, cost-effective, and accessible candidates for global use, specifically in low and middle-income countries. Here, we report the efficacy of a rapidly scalable, novel yeast expressed SARS-CoV-2 specific receptor-binding domain (RBD) based vaccine in rhesus macaques. We formulated the RBD immunogen in alum, a licensed and an emerging alum adsorbed TLR-7/8 targeted, 3M-052-alum adjuvants. The RBD+3M-052-alum adjuvanted vaccine promoted better RBD binding and effector antibodies, higher CoV-2 neutralizing antibodies, improved Th1 biased CD4+T cell reactions, and increased CD8+ T cell responses when compared to the alum-alone adjuvanted vaccine. RBD+3M-052-alum induced a significant reduction of SARS-CoV-2 virus in respiratory tract upon challenge, accompanied by reduced lung inflammation when compared with unvaccinated controls. Anti-RBD antibody responses in vaccinated animals inversely correlated with viral load in nasal secretions and BAL. RBD+3M-052-alum blocked a post SARS-CoV-2 challenge increase in CD14+CD16++ intermediate blood monocytes, and Fractalkine, MCP-1, and TRAIL in the plasma. Decreased plasma analytes and intermediate monocyte frequencies correlated with reduced nasal and BAL viral loads. Lastly, RBD-specific plasma cells accumulated in the draining lymph nodes and not in the bone marrow, contrary to previous findings. Together, these data show that a yeast expressed, RBD-based vaccine+3M-052-alum provides robust immune responses and protection against SARS-CoV-2, making it a strong and scalable vaccine candidate.

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Protective Vaccine Efficacy of the Complete Form of PPE39 Protein from Mycobacterium tuberculosis Beijing/K Strain in Mice

Clinical and Vaccine Immunology ◽

10.1128/cvi.00219-17 ◽

2017 ◽

Vol 24 (11) ◽

Cited By ~ 4

Author(s):

Ahreum Kim ◽

Yun-Gyoung Hur ◽

Sunwha Gu ◽

Sang-Nae Cho

Keyword(s):

T Cells ◽

Mycobacterium Tuberculosis ◽

T Cell ◽

Vaccine Development ◽

Protective Efficacy ◽

Interleukin 2 ◽

T Cell Epitopes ◽

Content Type ◽

Complete Form ◽

Ifn Γ

ABSTRACT The aim of this study was to evaluate the protective efficacy of MTBK_24820, a complete form of PPE39 protein derived from a predominant Beijing/K strain of Mycobacterium tuberculosis in South Korea. Mice were immunized with MTKB_24820, M. bovis Bacilli Calmette-Guérin (BCG), or adjuvant prior to a high-dosed Beijing/K strain aerosol infection. After 4 and 9 weeks, bacterial loads were determined and histopathologic and immunologic features in the lungs and spleens of the M. tuberculosis-infected mice were analyzed. Putative immunogenic T-cell epitopes were examined using synthetic overlapping peptides. Successful immunization of MTBK_24820 in mice was confirmed by increased IgG responses (P < 0.05) and recalled gamma interferon (IFN-γ), interleukin-2 (IL-2), IL-6, and IL-17 responses (P < 0.05 or P < 0.01) to MTBK_24820. After challenge with the Beijing/K strain, an approximately 0.5 to 1.0 log10 reduction in CFU in lungs and fewer lung inflammation lesions were observed in MTBK_24820-immunized mice compared to those for control mice. Moreover, MTBK_24820 immunization elicited significantly higher numbers of CD4+ T cells producing protective cytokines, such as IFN-γ and IL-17, in lungs and spleens (P < 0.01) and CD4+ multifunctional T cells producing IFN-γ, tumor necrosis factor alpha (TNF-α), and/or IL-17 (P < 0.01) than in control mice, suggesting protection comparable to that of BCG against the hypervirulent Beijing/K strain. The dominant immunogenic T-cell epitopes that induced IFN-γ production were at the N terminus (amino acids 85 to 102 and 217 to 234). Its vaccine potential, along with protective immune responses in vivo, may be informative for vaccine development, particularly in regions where the M. tuberculosis Beijing/K-strain is frequently isolated from TB patients.

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Development and Applications of Viral Vectored Vaccines to Combat Zoonotic and Emerging Public Health Threats

Vaccines ◽

10.3390/vaccines8040680 ◽

2020 ◽

Vol 8 (4) ◽

pp. 680

Author(s):

Sophia M. Vrba ◽

Natalie M. Kirk ◽

Morgan E. Brisse ◽

Yuying Liang ◽

Hinh Ly

Keyword(s):

Public Health ◽

Vaccine Development ◽

Yellow Fever Virus ◽

Protective Efficacy ◽

Cost Effective ◽

Vaccine Vectors ◽

Advantages And Disadvantages ◽

Viral Vaccine ◽

Health Threats ◽

Syncytial Virus

Vaccination is arguably the most cost-effective preventative measure against infectious diseases. While vaccines have been successfully developed against certain viruses (e.g., yellow fever virus, polio virus, and human papilloma virus HPV), those against a number of other important public health threats, such as HIV-1, hepatitis C, and respiratory syncytial virus (RSV), have so far had very limited success. The global pandemic of COVID-19, caused by the SARS-CoV-2 virus, highlights the urgency of vaccine development against this and other constant threats of zoonotic infection. While some traditional methods of producing vaccines have proven to be successful, new concepts have emerged in recent years to produce more cost-effective and less time-consuming vaccines that rely on viral vectors to deliver the desired immunogens. This review discusses the advantages and disadvantages of different viral vaccine vectors and their general strategies and applications in both human and veterinary medicines. A careful review of these issues is necessary as they can provide important insights into how some of these viral vaccine vectors can induce robust and long-lasting immune responses in order to provide protective efficacy against a variety of infectious disease threats to humans and animals, including those with zoonotic potential to cause global pandemics.

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Immunogenicity and Cross-Reactivity of Rhesus Adenoviral Vectors

Journal of Virology ◽

10.1128/jvi.00159-18 ◽

2018 ◽

Vol 92 (11) ◽

Cited By ~ 2

Author(s):

M. Justin Iampietro ◽

Rafael A. Larocca ◽

Nicholas M. Provine ◽

Peter Abbink ◽

Zi Han Kang ◽

...

Keyword(s):

T Cell ◽

Neutralizing Antibodies ◽

Vaccine Development ◽

T Cell Responses ◽

Adenoviral Vectors ◽

Cross Reactivity ◽

Human Populations ◽

Humoral Immune ◽

Cell Responses ◽

The Impact

ABSTRACT Adenovirus (Ad) vectors are being investigated as vaccine candidates, but baseline antivector immunity exists in human populations to both human Ad (HuAd) and chimpanzee Ad (ChAd) vectors. In this study, we investigated the immunogenicity and cross-reactivity of a panel of recently described rhesus adenoviral (RhAd) vectors. RhAd vectors elicited T cells with low exhaustion markers and robust anamnestic potential. Moreover, RhAd vector immunogenicity was unaffected by high levels of preexisting anti-HuAd immunity. Both HuAd/RhAd and RhAd/RhAd prime-boost vaccine regimens were highly immunogenic, despite a degree of cross-reactive neutralizing antibodies (NAbs) between phylogenetically related RhAd vectors. We observed extensive vector-specific cross-reactive CD4 T cell responses and more limited CD8 T cell responses between RhAd and HuAd vectors, but the impact of vector-specific cellular responses was far less than that of vector-specific NAbs. These data suggest the potential utility of RhAd vectors and define novel heterologous prime-boost strategies for vaccine development. IMPORTANCE To date, most adenoviral vectors developed for vaccination have been HuAds from species B, C, D, and E, and human populations display moderate to high levels of preexisting immunity. There is a clinical need for new adenoviral vectors that are not hindered by preexisting immunity. Moreover, the development of RhAd vector vaccines expands our ability to vaccinate against multiple pathogens in a population that may have received other HuAd or ChAd vectors. We evaluated the immunogenicity and cross-reactivity of RhAd vectors, which belong to the poorly described adenovirus species G. These vectors induced robust cellular and humoral immune responses and were not hampered by preexisting anti-HuAd vector immunity. Such properties make RhAd vectors attractive as potential vaccine vectors.

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Expression and Solubilization of Insect Cell-Based Rabies Virus Glycoprotein and Assessment of Its Immunogenicity and Protective Efficacy in Mice

Clinical and Vaccine Immunology ◽

10.1128/cvi.05258-11 ◽

2011 ◽

Vol 18 (10) ◽

pp. 1673-1679 ◽

Cited By ~ 15

Author(s):

R. Ramya ◽

B. Mohana Subramanian ◽

V. Sivakumar ◽

R. L. Senthilkumar ◽

K. R. S. Sambasiva Rao ◽

...

Keyword(s):

Rabies Virus ◽

Insect Cell ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

Vaccine Development ◽

Protective Efficacy ◽

Vector System ◽

Soluble Form ◽

Rabies Virus Glycoprotein ◽

Virus Glycoprotein

ABSTRACTRabies is a fatal zoonotic disease of serious public health and economic significance worldwide. The rabies virus glycoprotein (RVG) has been the major target for subunit vaccine development, since it harbors domains responsible for induction of virus-neutralizing antibodies, infectivity, and neurovirulence. The glycoprotein (G) was cloned using the baculovirus expression vector system (BEVS) and expressed inSpodoptera frugiperda(Sf-9) cells. In order to obtain a soluble form of G suitable for experimentation in mice, 18 different combinations of buffers and detergents were evaluated for their ability to solubilize the insect cell membrane-associated G. The combination that involved 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) detergent in lysis buffer 1, formulated with Tris, NaCl, 10% dimethyl sulfoxide (DMSO), and EDTA, gave the highest yield of soluble G, as evidenced by the experimental data. Subsequently, several other parameters, such as the concentration of CHAPS and the duration and temperature of the treatment for the effective solubilization of G, were optimized. The CHAPS detergent, buffered at a concentration of 0.4% to 0.7% (wt/vol) at room temperature (23 to 25°C) for 30 min to 1 h using buffer 1, containing 10% DMSO, resulted in consistently high yields. The G solubilized using CHAPS detergent was found to be immunogenic when tested in mice, as evidenced by high virus-neutralizing antibody titers in sera and 100% protection upon virulent intracerebral challenge with the challenge virus standard (CVS) strain of rabies virus. The results of the mice study indicated that G solubilized with CHAPS detergent retained the immunologically relevant domains in the native conformation, thereby paving the way for producing a cell-free and efficacious subunit vaccine.

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A Rapid Bead-Based Assay For Screening Of SARS-CoV-2 Neutralising Antibodies

10.1101/2021.10.13.464050 ◽

2021 ◽

Author(s):

Santhik SL ◽

Pramod Darvin ◽

Aneesh Chandrasekharan ◽

Shanakara Narayanan Varadarajan ◽

Soumya Jaya Divakaran ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Fluorescent Protein ◽

Vaccine Development ◽

Neutralizing Antibody ◽

Life Time ◽

Cost Effective ◽

Fluorescent Imaging ◽

Antibody Detection ◽

Screening Assay ◽

Live Virus

Quantitative determination of neutralizing antibodies against SARS CoV2 is of paramount importance in immunodiagnostics, vaccine efficacy testing, and immune response profiling among the vaccinated population. Cost effective, rapid, easy-to-perform assays are essential to support the vaccine development process and immunosurveillance studies. Here, we describe a bead based screening assay for S1 neutralization using recombinant fluorescent proteins of hACE2 and SARS CoV2 S1, immobilized on solid beads employing nanobodies /metal-affinity tags. Nanobody-mediated capture of SARS CoV2 Spike (S1) on agarose beads served as the trap for soluble recombinant ACE2-GFPSpark, inhibited by neutralizing antibody. The first approach demonstrates single color fluorescent imaging of ACE2 GFPspark binding to His tagged S1 Receptor Binding Domain (RBD His) immobilized beads. The second approach is dual color imaging of soluble ACE2 GFPSpark to S1 Orange Fluorescent Protein (S1 OFPSpark) beads. Both methods showed a good correlation with the gold standard pseudovirion assay and can be adapted to any fluorescent platforms for screening. Life time imaging of the ACE2 GFPSpark confirmed the interaction of ACE2 and S1 OFPSpark on beads. The self-renewable source of secreted recombinant proteins from stable cells and its direct use without necessitating purification renders the platform a cost-effective and rapid one than the popular pseudovirion assay and live virus-based assays. Any laboratory with minimum expertise can rapidly perform this bead assay for neutralizing antibody detection using stable engineered cells.

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Control of SARS-CoV-2 infection after Spike DNA or Spike DNA+Protein co-immunization in rhesus macaques

10.1101/2021.06.11.448032 ◽

2021 ◽

Author(s):

Margherita Rosati ◽

Mahesh Agarwal ◽

Xintao Hu ◽

Santhi Devasundaram ◽

Dimitris Stellas ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Protective Efficacy ◽

Rhesus Macaques ◽

Neutralizing Antibody ◽

Anatomical Site ◽

Cell Responses ◽

Cellular Immune Responses ◽

Antibody Titers ◽

Cellular Immune

The speed of development, versatility and efficacy of mRNA-based vaccines have been amply demonstrated in the case of SARS-CoV-2. DNA vaccines represent an important alternative since they induce both humoral and cellular immune responses in animal models and in human trials. We tested the immunogenicity and protective efficacy of DNA-based vaccine regimens expressing different prefusion-stabilized SARS-CoV-2 Spike antigens upon intramuscular injection followed by electroporation in rhesus macaques. Different Spike DNA vaccine regimens induced antibodies that potently neutralized SARS-CoV-2 in vitro and elicited robust T cell responses. The DNA-only vaccine regimens were compared to a regimen that included co-immunization of Spike DNA and protein in the same anatomical site, the latter of which showed significant higher antibody responses. All vaccine regimens led to control of SARS-CoV-2 intranasal/intratracheal challenge and absence of virus dissemination to the lower respiratory tract. Vaccine-induced binding and neutralizing antibody titers and antibody-dependent cellular phagocytosis inversely correlated with transient virus levels in the nasal mucosa. Importantly, the Spike DNA+Protein co-immunization regimen induced the highest binding and neutralizing antibodies and showed the strongest control against SARS-CoV-2 challenge in rhesus macaques.

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Identification and tracking of alloreactive T cell clones in Rhesus Macaques through the RM-scTCR-Seq platform.

10.1101/2021.10.29.466482 ◽

2021 ◽

Author(s):

Ulrike Gerdemann ◽

Ryan A. Fleming ◽

James Kaminski ◽

Connor McGuckin ◽

Xianliang Rui ◽

...

Keyword(s):

T Cell ◽

T Cell Receptor ◽

Vaccine Development ◽

Rhesus Macaques ◽

Single Cells ◽

Cell Receptor ◽

Cytotoxic T Cell ◽

Cell Clones ◽

Alloreactive T Cell

T cell receptor clonotype tracking is a powerful tool for interrogating T cell mediated immune processes. New methods to pair a single cells transcriptional program with its T cell receptor (TCR) identity allow monitoring of T cell clonotype-specific transcriptional dynamics. While these technologies have been available for human and mouse T cells studies, they have not been developed for Rhesus Macaques, a critical translational organism for autoimmune diseases, vaccine development and transplantation. We describe a new pipeline, RM-scTCR-Seq, which, for the first time, enables RM specific single cell TCR amplification, reconstitution and pairing of RM TCRs with their transcriptional profiles. We apply this method to a RM model of GVHD, and identify and track in vitro detected alloreactive clonotypes in GVHD target organs and explore their GVHD driven cytotoxic T cell signature. This novel, state-of-the-art platform fundamentally advances the utility of RM to study protective and pathogenic T cell responses.

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Designing multiepitope-based vaccine against Eimeria from immune mapped protein 1 (IMP-1) antigen using immunoinformatic approach

Scientific Reports ◽

10.1038/s41598-021-97880-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Thabile Madlala ◽

Victoria T. Adeleke ◽

Abiodun J. Fatoba ◽

Moses Okpeku ◽

Adebayo A. Adeniyi ◽

...

Keyword(s):

T Cell ◽

B Cell ◽

Vaccine Development ◽

Cell Epitope ◽

Docking Simulation ◽

Cost Effective ◽

Economic Loss ◽

T Cell Epitopes ◽

Live Vaccines ◽

Physiochemical Parameters

AbstractDrug resistance against coccidiosis has posed a significant threat to chicken welfare and productivity worldwide, putting daunting pressure on the poultry industry to reduce the use of chemoprophylactic drugs and live vaccines in poultry to treat intestinal diseases. Chicken coccidiosis, caused by an apicomplexan parasite of Eimeria spp., is a significant challenge worldwide. Due to the experience of economic loss in production and prevention of the disease, development of cost-effective vaccines or drugs that can stimulate defence against multiple Eimeria species is imperative to control coccidiosis. This study explored Eimeria immune mapped protein-1 (IMP-1) to develop a multiepitope-based vaccine against coccidiosis by identifying antigenic T-cell and B-cell epitope candidates through immunoinformatic techniques. This resulted in the design of 7 CD8+, 21 CD4+ T-cell epitopes and 6 B-cell epitopes, connected using AAY, GPGPG and KK linkers to form a vaccine construct. A Cholera Toxin B (CTB) adjuvant was attached to the N-terminal of the multiepitope construct to improve the immunogenicity of the vaccine. The designed vaccine was assessed for immunogenicity (8.59968), allergenicity and physiochemical parameters, which revealed the construct molecular weight of 73.25 kDa, theoretical pI of 8.23 and instability index of 33.40. Molecular docking simulation of vaccine with TLR-5 with binding affinity of − 151.893 kcal/mol revealed good structural interaction and stability of protein structure of vaccine construct. The designed vaccine predicts the induction of immunity and boosted host's immune system through production of antibodies and cytokines, vital in hindering surface entry of parasites into host. This is a very important step in vaccine development though further experimental study is still required to validate these results.

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SARS-CoV-2 binding and neutralizing antibody levels after vaccination with Ad26.COV2.S predict durable protection in rhesus macaques

10.1101/2021.01.30.428921 ◽

2021 ◽

Author(s):

Ramon Roozendaal ◽

Laura Solforosi ◽

Daniel Stieh ◽

Jan Serroyen ◽

Roel Straetemans ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Protective Efficacy ◽

Rhesus Macaques ◽

Natural Infection ◽

Neutralizing Antibody ◽

Preliminary Evidence ◽

Correlates Of Protection ◽

Antibody Titers ◽

Antibody Levels ◽

The Relationship

The first COVID-19 vaccines have recently gained authorization for emergency use.1,2 At this moment, limited knowledge on duration of immunity and efficacy of these vaccines is available. Data on other coronaviruses after natural infection suggest that immunity to SARS-CoV-2 might be short lived,3,4 and preliminary evidence indicates waning antibody titers following SARS-CoV-2 infection.5 Here we model the relationship between immunogenicity and protective efficacy of a series of Ad26 vectors encoding stabilized variants of the SARS-CoV-2 Spike (S) protein in rhesus macaques6,7,8 and validate the analyses by challenging macaques 6 months after immunization with the Ad26.COV2.S vaccine candidate that has been selected for clinical development. We find that Ad26.COV2.S confers durable protection against replication of SARS-CoV-2 in the lungs that is predicted by the levels of S-binding and neutralizing antibodies. These results suggest that Ad26.COV2.S could confer durable protection in humans and that immunological correlates of protection may enable the prediction of durability of protection.

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CD4+-T-Cell and CD20+-B-Cell Changes Predict Rapid Disease Progression after Simian-Human Immunodeficiency Virus Infection in Macaques

Journal of Virology ◽

10.1128/jvi.72.2.1600-1605.1998 ◽

1998 ◽

Vol 72 (2) ◽

pp. 1600-1605 ◽

Cited By ~ 31

Author(s):

Krista K. Steger ◽

Marta Dykhuizen ◽

Jacque L. Mitchen ◽

Paul W. Hinds ◽

Brenda L. Preuninger ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

T Cells ◽

T Cell ◽

B Cells ◽

Neutralizing Antibodies ◽

Rhesus Macaques ◽

Rapid Progression ◽

Virus Binding ◽

Immunodeficiency Virus ◽

Progression Of Disease

ABSTRACT Simian-human immunodeficiency virus 89.6PD (SHIV89.6PD) was pathogenic after intrarectal inoculation of rhesus macaques. Infection was achieved with a minimum of 2,500 tissue culture infectious doses of cell-free virus stock, and there was no evidence for transient viremia in animals receiving subinfectious doses by the intrarectal route. Some animals experienced rapid progression of disease characterized by loss of greater than 90% of circulating CD4+ T cells, sustained decreases in CD20+ B cells, failure to elicit virus-binding antibodies in plasma, and high levels of antigenemia. Slower-progressing animals had moderate but varying losses of CD4+ T cells; showed increases in circulating CD20+ B cells; mounted vigorous responses to antibodies in plasma, including neutralizing antibodies; and had low or undetectable levels of antigenemia. Rapid progression led to death within 30 weeks after intrarectal inoculation. Plasma antigenemia at 2 weeks after inoculation (P ≤ 0.002), B- and T-cell losses (P ≤ 0.013), and failure to seroconvert (P ≤ 0.005) were correlated statistically with rapid progression. Correlations were evident by 2 to 4 weeks after intrarectal SHIV inoculation, indicating that early events in the host-pathogen interaction determined the clinical outcome.

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