Vaccine comprising anti-idiotype antibody conjugate; induces production of neutralizing antibody (human monoclonal antibody, chimeric antibody or FAb, F(Ab′) 2 or Fv fragment) against HIV virus-1

ABSTRACTHuman parechovirus 3 (HPeV3) infection is associated with sepsis characterized by significant immune activation and subsequent tissue damage in neonates. Strategies to limit infection have been unsuccessful due to inadequate molecular diagnostic tools for early detection and the lack of a vaccine or specific antiviral therapy. Toward the latter, we present a 2.8-Å-resolution structure of HPeV3 in complex with fragments from a neutralizing human monoclonal antibody, AT12-015, using cryo-electron microscopy (cryo-EM) and image reconstruction. Modeling revealed that the epitope extends across neighboring asymmetric units with contributions from capsid proteins VP0, VP1, and VP3. Antibody decoration was found to block binding of HPeV3 to cultured cells. Additionally, at high resolution, it was possible to model a stretch of RNA inside the virion and, from this, identify the key features that drive and stabilize protein-RNA association during assembly.IMPORTANCEHuman parechovirus 3 (HPeV3) is receiving increasing attention as a prevalent cause of sepsis-like symptoms in neonates, for which, despite the severity of disease, there are no effective treatments available. Structural and molecular insights into virus neutralization are urgently needed, especially as clinical cases are on the rise. Toward this goal, we present the first structure of HPeV3 in complex with fragments from a neutralizing monoclonal antibody. At high resolution, it was possible to precisely define the epitope that, when targeted, prevents virions from binding to cells. Such an atomic-level description is useful for understanding host-pathogen interactions and viral pathogenesis mechanisms and for finding potential cures for infection and disease.

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Development and characterization of a pre-treatment procedure to eliminate human monoclonal antibody therapeutic drug and matrix interference in cell-based functional neutralizing antibody assays

Journal of Immunological Methods ◽

10.1016/j.jim.2014.11.005 ◽

2015 ◽

Vol 416 ◽

pp. 94-104 ◽

Cited By ~ 15

Author(s):

Weifeng Xu ◽

Hao Jiang ◽

Craig Titsch ◽

Jonathan R. Haulenbeek ◽

Renuka C. Pillutla ◽

...

Keyword(s):

Monoclonal Antibody ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

Therapeutic Drug ◽

Matrix Interference ◽

Treatment Procedure ◽

Antibody Assays ◽

Pre Treatment

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Generation and Activity Evaluation of a Mouse-Human Immunoglobulin G1 Chimeric Antibody to Histoplasma capsulatum HSP60

10.20944/preprints202104.0101.v1 ◽

2021 ◽

Author(s):

Ágata Nogueira D'Áurea Moura ◽

Scott J. Garforth ◽

Leandro Buffoni Roque da Silva ◽

Darien Woodley ◽

Filipe Vieira Barbalho ◽

...

Keyword(s):

Monoclonal Antibody ◽

Histoplasma Capsulatum ◽

Physiological Stress ◽

Human Monoclonal Antibody ◽

Current Treatment ◽

Chimeric Antibody ◽

Human Antibody ◽

Chimeric Mouse ◽

Dimorphic Fungi

Heat shock proteins (Hsps) are highly conserved molecules that are constitutively expressed and upregulated in response to physiological stress conditions. These immunogenic chaperones can have essential functions in fungi, particularly in dimorphic pathogens. Histoplasma capsulatum and Paracoccidioides species are dimorphic fungi that are the causative agents of histoplasmosis and paracoccidioidomycosis, respectively, which are systemic mycoses with significant rates of morbidity and mortality. Current treatment consists of long-term antifungal agents, and there is an urgent need for new therapeutic approaches with higher efficacy, lower toxicity, better biodistribution and improved selectivity. We engineered an immunoglobulin G1 (IgG1) isotype chimeric mouse-human monoclonal antibody, titled ch-MAb 4E12, from the parental IgG2a MAb 4E12, a monoclonal antibody to H. capsulatum Hsp60 that is protective in experimental histoplasmosis and paracoccidioidomycosis models elicited by H. capsulatum var. capsulatum and Paracoccidioides lutzii, respectively. The ch-MAb 4E12 increased phagolysosomal fusion and enhanced the yeasts uptake by PMA differentiated human THP1 macrophage cells in vitro. At low concentrations, the chimeric antibody significantly reduced the pulmonary and splenic fungal burden compared to an irrelevant antibody or no treatment. These results are the first to show that a chimeric mouse-human antibody can modify infection caused by dimorphic fungi.

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A human monoclonal antibody blocking SARS-CoV-2 infection

10.1101/2020.03.11.987958 ◽

2020 ◽

Cited By ~ 43

Author(s):

Chunyan Wang ◽

Wentao Li ◽

Dubravka Drabek ◽

Nisreen M.A. Okba ◽

Rien van Haperen ◽

...

Keyword(s):

Monoclonal Antibody ◽

Respiratory Disease ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

The Novel ◽

Targeted Therapeutics ◽

Human Coronavirus ◽

Prevention And Treatment

AbstractThe emergence of the novel human coronavirus SARS-CoV-2 in Wuhan, China has caused a worldwide epidemic of respiratory disease (COVID-19). Vaccines and targeted therapeutics for treatment of this disease are currently lacking. Here we report a human monoclonal antibody that neutralizes SARS-CoV-2 (and SARS-CoV). This cross-neutralizing antibody targets a communal epitope on these viruses and offers potential for prevention and treatment of COVID-19.

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Evaluation of Human Monoclonal Antibody 80R for Immunoprophylaxis of Severe Acute Respiratory Syndrome by an Animal Study, Epitope Mapping, and Analysis of Spike Variants

Journal of Virology ◽

10.1128/jvi.79.10.5900-5906.2005 ◽

2005 ◽

Vol 79 (10) ◽

pp. 5900-5906 ◽

Cited By ~ 100

Author(s):

Jianhua Sui ◽

Wenhui Li ◽

Anjeanette Roberts ◽

Leslie J. Matthews ◽

Akikazu Murakami ◽

...

Keyword(s):

Monoclonal Antibody ◽

Amino Acid ◽

Severe Acute Respiratory Syndrome ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

Index Patient ◽

Binding Domain ◽

S Protein

ABSTRACT In this report, the antiviral activity of 80R immunoglobulin G1 (IgG1), a human monoclonal antibody against severe acute respiratory syndrome coronavirus (SARS-CoV) spike (S) protein that acts as a viral entry inhibitor in vitro, was investigated in vivo in a mouse model. When 80R IgG1 was given prophylactically to mice at doses therapeutically achievable in humans, viral replication was reduced by more than 4 orders of magnitude to below assay limits. The essential core region of S protein required for 80R binding was identified as a conformationally sensitive fragment (residues 324 to 503) that overlaps the receptor ACE2-binding domain. Amino acids critical for 80R binding were identified. In addition, the effects of various 80R-binding domain amino acid substitutions which occur in SARS-like-CoV from civet cats, and which evolved during the 2002/2003 outbreak and in a 2003/2004 Guangdong index patient, were analyzed. The results demonstrated that the vast majority of SARS-CoVs are sensitive to 80R. We propose that by establishing the susceptibility and resistance profiles of newly emerging SARS-CoVs through early S1 genotyping of the core 180-amino-acid neutralizing epitope of 80R, an effective immunoprophylaxis strategy with 80R should be possible in an outbreak setting. Our study also cautions that for any prophylaxis strategy based on neutralizing antibody responses, whether by passive or active immunization, a genotyping monitor will be necessary for effective use.

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2.8 Å resolution cryo-EM structure of human parechovirus 3 in complex with Fab from a neutralizing antibody

10.1101/410217 ◽

2018 ◽

Cited By ~ 1

Author(s):

Aušra Domanska ◽

Justin W. Flatt ◽

Joonas J.J. Jukonen ◽

James A. Geraets ◽

Sarah J. Butcher

Keyword(s):

Monoclonal Antibody ◽

High Resolution ◽

Cultured Cells ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Human Parechovirus ◽

Neutralizing Monoclonal Antibody ◽

Specific Antiviral Therapy

AbstractHuman parechovirus 3 (HPeV3) infection is associated with sepsis in neonates characterized by significant immune activation and subsequent tissue damage. Strategies to limit infection have been unsuccessful due to inadequate molecular diagnostic tools for early detection and lack of a vaccine or specific antiviral therapy. Towards the latter, we present a 2.8 Å-resolution structure of HPeV3 in complex with fragments from a neutralizing human monoclonal antibody AT12-015 using cryo-EM and image reconstruction. Modeling revealed that the epitope extends across neighboring asymmetric units with contributions from capsid proteins VP0, VP1, and VP3. Antibody decoration was found to block binding of HPeV3 to cultured cells. Additionally at high-resolution, it was possible to model a stretch of RNA inside the virion and from this identify the key features that drive and stabilize protein-RNA association during assembly.ImportanceHPeV3 is receiving increasing attention as a prevalent cause of sepsis-like symptoms in neonates, which despite the severity of disease, there are no effective treatments available. Structural and molecular insights into virus neutralization are urgently needed, especially as clinical cases are on the rise. Towards this goal, we present the first structure of HPeV3 in complex with fragments from a neutralizing monoclonal antibody. At high-resolution it was possible to precisely define the epitope that when targeted, prevents virions from binding to cells. Such an atomic-level description is useful for understanding host-pathogen interaction, viral pathogenesis mechanisms, and for finding potential cures for infection and disease.

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Analysis of Individuals from a Dengue-Endemic Region Helps Define the Footprint and Repertoire of Antibodies Targeting Dengue Virus 3 Type-Specific Epitopes

mBio ◽

10.1128/mbio.01205-17 ◽

2017 ◽

Vol 8 (5) ◽

Cited By ~ 9

Author(s):

Daniela V. Andrade ◽

Leah C. Katzelnick ◽

Doug G. Widman ◽

Angel Balmaseda ◽

Aravinda M. de Silva ◽

...

Keyword(s):

Public Health ◽

Monoclonal Antibody ◽

Antibody Response ◽

Dengue Virus ◽

Vaccine Development ◽

Human Monoclonal Antibody ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Kinetics Of

ABSTRACT The four dengue virus serotypes (DENV1 to 4) cause dengue, a major public health problem worldwide. Individuals exposed to primary DENV infections develop serotype-specific neutralizing antibodies, including strongly neutralizing antibodies targeting quaternary epitopes. To date, no studies have measured the levels and kinetics of serum antibodies directed to such epitopes among populations in regions where dengue is endemic. Here, we use a recombinant DENV4 (rDENV4/3-M14) displaying a major DENV3 type-specific quaternary epitope recognized by human monoclonal antibody 5J7 to measure the proportion, magnitude, and kinetics of DENV3 type-specific neutralizing antibody responses targeting this epitope. Primary DENV3 sera from 30 individuals in a dengue hospital-based study in Nicaragua were studied 3, 6, 12, and 18 months post-infection, alongside samples collected annually 1 to 4 years post-primary DENV3 infection from 10 individuals in a cohort study in Nicaragua. We found substantial individual variation in the proportion of DENV3 type-specific neutralizing antibody titers attributed to the 5J7 epitope (range, 0 to 100%), with the mean significantly increasing from 22.6% to 41.4% from 3 to 18 months. We extended the transplanted DENV3 5J7 epitope on the virion (rDENV4/3-M16), resulting in increased recognition in several individuals, helping define the footprint of the epitope. However, 37% and 13% of the subjects still showed little to no recognition of the 5J7 epitope at 3 and 18 months, respectively, indicating that one or more additional DENV3 type-specific epitopes exist. Overall, this study demonstrates how DENV-immune plasma from populations from areas of endemicity, when coupled with structurally guided recombinant viruses, can help characterize the epitope-specific neutralizing antibody response in natural DENV infections, with direct implications for design and evaluation of dengue vaccines. IMPORTANCE The four serotypes of dengue virus cause dengue, a major public health burden worldwide, yet it has been challenging to develop a vaccine that is safe and equally effective against all four serotypes. More in-depth characterization of natural human neutralizing antibody responses is needed to identify determinants of protective antibody responses to all DENV serotypes. Here, we use hospital and cohort studies in a region where dengue is endemic to assess the proportion and kinetics of the DENV3 neutralizing antibody response directed to a quaternary epitope on DENV3 recognized by strongly neutralizing human monoclonal antibody 5J7, which was transplanted into a DENV4 backbone. We show that many individuals recognized the 5J7 epitope, but to various degrees over time, suggesting that additional DENV3-specific epitopes likely exist. Thus, characterization of epitope-specific neutralizing antibody responses in natural DENV infections can help define the footprint and repertoire of antibodies directed to DENV3 type-specific epitopes, with implications for dengue vaccine development. IMPORTANCE The four serotypes of dengue virus cause dengue, a major public health burden worldwide, yet it has been challenging to develop a vaccine that is safe and equally effective against all four serotypes. More in-depth characterization of natural human neutralizing antibody responses is needed to identify determinants of protective antibody responses to all DENV serotypes. Here, we use hospital and cohort studies in a region where dengue is endemic to assess the proportion and kinetics of the DENV3 neutralizing antibody response directed to a quaternary epitope on DENV3 recognized by strongly neutralizing human monoclonal antibody 5J7, which was transplanted into a DENV4 backbone. We show that many individuals recognized the 5J7 epitope, but to various degrees over time, suggesting that additional DENV3-specific epitopes likely exist. Thus, characterization of epitope-specific neutralizing antibody responses in natural DENV infections can help define the footprint and repertoire of antibodies directed to DENV3 type-specific epitopes, with implications for dengue vaccine development.

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