Identification of a Critical and Conformational Neutralizing Epitope in Human Adenovirus Type 4 Hexon

ABSTRACTHuman adenovirus type 4 (HAdV-4) is an epidemic virus that contributes to serious acute respiratory disease (ARD) in both pediatric and adult patients. However, no licensed drug or vaccine is currently available to the civilian population. The identification of neutralizing epitopes of HAdV-4 should allow the development of a novel antiviral vaccine and a novel gene transfer vector, and an effective neutralizing monoclonal antibody (MAb) will be useful in developing appropriate antiviral drugs. In this study, we report that MAb MN4b shows strong neutralizing activity against HAdV-4. MN4b recognizes a conformational epitope (418AGSEK422) within hypervariable region 7 (HVR7). Mutations within this site permitted HAdV-4 mutants to escape neutralization by MN4b and to resist neutralization by animal and human anti-HAdV-4 sera. A recombinant virus, rAd3-A4R7-1, containing the identified neutralizing epitope in the HVR7 region of HAdV-3 hexon, successfully induced antiserum that inhibited HAdV-4 infection. These results indicate that a small surface loop of HAdV-4 hexon is a critical neutralization epitope for this virus. The generation of MN4b and the identification of this neutralizing epitope may be useful in developing therapeutic treatment, a subunit vaccine, and a novel vector that can escape preexisting neutralization for HAdV-4.IMPORTANCENeutralizing antibodies are considered good tools for the prevention of human adenovirus type 4 (HAdV-4) infections. The identification of the epitopes recognized by such neutralizing antibodies is important for the generation of recombinant antiviral vaccines. However, until now, no neutralizing epitope has been reported for HAdV-4. Here, we developed a serotype-specific neutralizing MAb directed against HAdV-4, MN4b. We provide evidence that MN4b recognizes a conformational epitope within HVR7 of HAdV-4 hexon. Antisera generated to this conformational epitope displayed on HAdV-3 hexon inhibited infection of AD293 cells by HAdV-4. Our findings are very important for the development of therapeutic treatment, a subunit vaccine, and a novel vector for HAdV-4.

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Hexon Hypervariable Region-Modified Adenovirus Type 5 (Ad5) Vectors Display Reduced Hepatotoxicity but Induce T Lymphocyte Phenotypes Similar to Ad5 Vectors

Clinical and Vaccine Immunology ◽

10.1128/cvi.00207-14 ◽

2014 ◽

Vol 21 (8) ◽

pp. 1137-1144 ◽

Cited By ~ 7

Author(s):

Jeffrey E. Teigler ◽

Pablo Penaloza-MacMaster ◽

Rebecca Obeng ◽

Nicholas M. Provine ◽

Rafael A. Larocca ◽

...

Keyword(s):

Immune Responses ◽

Neutralizing Antibodies ◽

Hypervariable Region ◽

Adenovirus Type ◽

Adaptive Immune Responses ◽

Adaptive Immune ◽

Cytokines And Chemokines ◽

Programmed Death 1 ◽

Lymphocyte Phenotypes ◽

Adenovirus Type 5

ABSTRACTHexon modification of adenovirus type 5 (Ad5) vectors with the hypervariable regions (HVRs) of Ad48 has been shown to allow Ad5HVR48 vectors to circumvent the majority of the preexisting Ad5-neutralizing antibodies. However, it remains unclear whether modifying hexon HVRs impacts innate or adaptive immune responses elicited by this vector. In this study, we investigated the influence of the HVR substitution of Ad5 on innate and adaptive immune responses following vaccination. Ad5HVR48 displayed an intermediate level of innate immune cytokines and chemokines relative to those of Ad5 and Ad48, consistent with its chimeric nature. Hepatotoxicity was observed after Ad5 immunization but not after Ad5HVR48 or Ad48 immunization. However, the CD8+T-cell responses elicited by Ad5HVR48 vectors displayed a partially exhausted phenotype, as evidenced by the sustained expression of programmed death 1 (PD-1), decreased effector-to-central memory conversion, and reduced memory recall responses, similar to those elicited by Ad5 vectors and in contrast to those induced by Ad48 vectors. Taken together, these results indicate that although Ad5HVR48 largely bypasses preexisting Ad5 neutralizing antibodies and shows reduced hepatotoxicity compared to that of Ad5, it induces adaptive immune phenotypes that are functionally exhausted similar to those elicited by Ad5.

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Mucosal Targeting of a BoNT/A Subunit Vaccine Adjuvanted with a Mast Cell Activator Enhances Induction of BoNT/A Neutralizing Antibodies in Rabbits

PLoS ONE ◽

10.1371/journal.pone.0016532 ◽

2011 ◽

Vol 6 (1) ◽

pp. e16532 ◽

Cited By ~ 31

Author(s):

Herman F. Staats ◽

Jeffrey R. Fielhauer ◽

Afton L. Thompson ◽

Alice A. Tripp ◽

Ashley E. Sobel ◽

...

Keyword(s):

Mast Cell ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

A Subunit ◽

Cell Activator ◽

Mast Cell Activator

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Construction and immunogenic studies of a mFc fusion receptor binding domain (RBD) of spike protein as a subunit vaccine against SARS-CoV-2 infection

Chemical Communications ◽

10.1039/d0cc03263h ◽

2020 ◽

Vol 56 (61) ◽

pp. 8683-8686 ◽

Cited By ~ 5

Author(s):

Xiaoxiao Qi ◽

Bixia Ke ◽

Qian Feng ◽

Deying Yang ◽

Qinghai Lian ◽

...

Keyword(s):

Amino Acid ◽

Fusion Protein ◽

Receptor Binding ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

Binding Domain ◽

Spike Protein ◽

Receptor Binding Domain ◽

Humoral And Cellular Immunity ◽

A Subunit

Herein, we report that a recombinant fusion protein, containing a 457 amino acid SARS-CoV-2 receptor binding domain and a mouse IgG1 Fc domain, could induce highly potent neutralizing antibodies and stimulate humoral and cellular immunity in mice.

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Seroprevalence of Neutralizing Antibodies to Human Adenovirus Type 4 and 7 in Healthy Populations From Southern China

Frontiers in Microbiology ◽

10.3389/fmicb.2018.03040 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 4

Author(s):

Xianmiao Ye ◽

Lijun Xiao ◽

Xuehua Zheng ◽

Jinlin Wang ◽

Tao Shu ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Southern China ◽

Human Adenovirus ◽

Adenovirus Type

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Seroprevalence of neutralizing antibodies against human adenovirus type 55 in the South Korean military, 2018-2019

PLoS ONE ◽

10.1371/journal.pone.0236040 ◽

2020 ◽

Vol 15 (7) ◽

pp. e0236040

Author(s):

So Yun Park ◽

Jae-Hoon Ko ◽

Sezim Monoldorova ◽

Jonguk Jeong ◽

Bo-Young Jeon ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Human Adenovirus ◽

Adenovirus Type ◽

The South ◽

South Korean

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Immunogenicity of an E1-deleted recombinant human adenovirus against rabies by different routes of administration

Journal of General Virology ◽

10.1099/0022-1317-82-9-2191 ◽

2001 ◽

Vol 82 (9) ◽

pp. 2191-2197 ◽

Cited By ~ 32

Author(s):

Ad Vos ◽

Andreas Neubert ◽

Elke Pommerening ◽

Thomas Müller ◽

Leopold Döhner ◽

...

Keyword(s):

Immune Response ◽

Oral Administration ◽

Neutralizing Antibodies ◽

Direct Injection ◽

Human Adenovirus ◽

Adenovirus Type ◽

Vaccine Virus ◽

Strong Immune Response ◽

Routes Of Administration ◽

Immunogenic Properties

The immunogenic properties of an E1-deleted, human adenovirus type 5 (Ad5) vaccine virus with activity against rabies were examined in mice, foxes and dogs using different routes of administration. NMRI mice received 105·8, 105·3, 104·3, 103·3 and 102·3 TCID50 by peroral or intramuscular (i.m.) administration. Furthermore, six mice received 105·8 TCID50 intracerebrally (i.c.). The construct elicited marked seroconversion in mice after oral administration. Immunoreactivity in mice was even more pronounced i.m. and i.c. After direct oral administration (108·0 TCID50) in foxes, six of eight animals developed rabies virus-neutralizing antibodies (VNA). All foxes immunized by direct injection (107·7 TCID50) in the membrane of the jejunum were shown to seroconvert. Pre-existing immunity against canine adenovirus did not hinder the development of rabies VNA after oral application of the construct (108·0 TCID50). Fox cubs (24–29 days old) born from rabies-immune vixens were shown to develop very high levels of rabies VNA after i.m. administration (108·0 TCID50), indicating that the immunogenicity of the construct could surpass maternally transferred immunity. In dogs, the construct (108·0 TCID50) induced a very strong immune response after i.m. administration. However, no immune response was detectable in dogs after direct oral administration (108·3 TCID50) or after endoscopic deposition in the smaller intestine (108·0 TCID50). Hence, it must be concluded that the construct is not suitable for oral vaccination of dogs against rabies.

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Biochemical and Immunological Evaluation of Recombinant CS6-Derived Subunit EnterotoxigenicEscherichia coliVaccine Candidates

Infection and Immunity ◽

10.1128/iai.00788-18 ◽

2019 ◽

Vol 87 (3) ◽

Cited By ~ 4

Author(s):

Steven T. Poole ◽

Milton Maciel ◽

Premkumar Dinadayala ◽

Kathleen E. Dori ◽

Annette L. McVeigh ◽

...

Keyword(s):

Immune Responses ◽

Recombinant Proteins ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

Vaccine Strategy ◽

Content Type ◽

A Subunit ◽

Folded Proteins ◽

Immunological Evaluation

ABSTRACTCS6, a prevalent surface antigen expressed in nearly 20% of clinical enterotoxigenicEscherichia coli(ETEC) isolates, is comprised of two major subunit proteins, CssA and CssB. Using donor strand complementation, we constructed a panel of recombinant proteins of 1 to 3 subunits that contained combinations of CssA and/or CssB subunits and a donor strand, a C-terminal extension of 16 amino acids that was derived from the N terminus of either CssA or CssB. While the entire panel of recombinant proteins could be obtained as soluble, folded proteins, it was observed that the proteins possessing a heterologous donor strand, derived from the CS6 subunit different from the C-terminal subunit, had the highest degree of physical and thermal stability. Immunological characterization of the proteins, using a murine model, demonstrated that robust anti-CS6 immune responses were generated from fusions containing both CssA and CssB. Proteins containing only CssA were weakly immunogenic. Heterodimers, i.e., CssBA and CssAB, were sufficient to recapitulate the anti-CS6 immune response elicited by immunization with CS6, including the generation of functional neutralizing antibodies, as no further enhancement of the response was obtained with the addition of a third CS6 subunit. Our findings here demonstrate the feasibility of including a recombinant CS6 subunit protein in a subunit vaccine strategy against ETEC.

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Development and Assessment of Human Adenovirus Type 11 as a Gene Transfer Vector

Journal of Virology ◽

10.1128/jvi.79.8.5090-5104.2005 ◽

2005 ◽

Vol 79 (8) ◽

pp. 5090-5104 ◽

Cited By ~ 80

Author(s):

Daniel Stone ◽

Shaoheng Ni ◽

Zong-Yi Li ◽

Anuj Gaggar ◽

Nelson DiPaolo ◽

...

Keyword(s):

Gene Transfer ◽

Neutralizing Antibodies ◽

Human Adenovirus ◽

Adenovirus Type ◽

Cell Types ◽

Widespread Application ◽

Human Cd34 ◽

Immature Dendritic Cells

ABSTRACT Adenovirus vectors based on human serotype 5 (Ad5) have successfully been used as gene transfer vectors in many gene therapy-based approaches to treat disease. Despite their widespread application, many potential therapeutic applications are limited by the widespread prevalence of vector-neutralizing antibodies within the human population and the inability of Ad5-based vectors to transduce important therapeutic target cell types. In an attempt to circumvent these problems, we have developed Ad vectors based on human Ad serotype 11 (Ad11), since the prevalence of neutralizing antibodies to Ad11 in humans is low. E1-deleted Ad11 vector genomes were generated by homologous recombination in 293 cells expressing the Ad11-E1B55K protein or by recombination in Escherichia coli. E1-deleted Ad11 genomes did not display transforming activity in rodent cells. Transduction of primary human CD34+ hematopoietic progenitor cells and immature dendritic cells was more efficient with Ad11 vectors than with Ad5 vectors. Thirty minutes after intravenous injection into mice that express one of the Ad11 receptors (CD46), we found, in a pattern and at a level comparable to what is found in humans, Ad11 vector genomes in all analyzed organs, with the highest amounts in liver, lung, kidney, and spleen. Neither Ad11 genomes nor Ad11 vector-mediated transgene expression were, however, detected at 72 h postinfusion. A large number of Ad11 particles were also found to be associated with circulating blood cells. We also discovered differences in in vitro transduction efficiencies and in vivo biodistributions between Ad11 vectors and chimeric Ad5 vectors possessing Ad11 fibers, indicating that Ad11 capsid proteins other than fibers influence viral infectivity and tropism. Overall, our study provides a basis for the application of Ad11 vectors for in vitro and in vivo gene transfer and for gaining an understanding of the factors that determine Ad tropism.

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Replication-Defective Vector Based on a Chimpanzee Adenovirus

Journal of Virology ◽

10.1128/jvi.75.23.11603-11613.2001 ◽

2001 ◽

Vol 75 (23) ◽

pp. 11603-11613 ◽

Cited By ~ 189

Author(s):

Steven F. Farina ◽

Guang-ping Gao ◽

Z. Q. Xiang ◽

John J. Rux ◽

Roger M. Burnett ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Human Adenovirus ◽

Adenovirus Type ◽

Open Reading Frames ◽

Hypervariable Regions ◽

293 Cells ◽

Coxsackievirus And Adenovirus Receptor ◽

Cross Neutralization ◽

Adenovirus Receptor ◽

Adenovirus Type 5

ABSTRACT An adenovirus previously isolated from a mesenteric lymph node from a chimpanzee was fully sequenced and found to be similar in overall structure to human adenoviruses. The genome of this virus, called C68, is 36,521 bp in length and is most similar to subgroup E of human adenovirus, with 90% identity in most adenovirus type 4 open reading frames that have been sequenced. Substantial differences in the hexon hypervariable regions were noted between C68 and other known adenoviruses, including adenovirus type 4. Neutralizing antibodies to C68 were highly prevalent in sera from a population of chimpanzees, while sera from humans and rhesus monkeys failed to neutralize C68. Furthermore, infection with C68 was not neutralized from sera of mice immunized with human adenovirus serotypes 2, 4, 5, 7, and 12. A replication-defective version of C68 was created by replacing the E1a and E1b genes with a minigene cassette; this vector was efficiently transcomplemented by the E1 region of human adenovirus type 5. C68 vector transduced a number of human and murine cell lines. This nonhuman adenoviral vector is sufficiently similar to human serotypes to allow growth in 293 cells and transduction of cells expressing the coxsackievirus and adenovirus receptor. As it is dissimilar in regions such as the hexon hypervariable domains, C68 vector avoids significant cross-neutralization by sera directed against human serotypes.

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