Development of an enzymatic assay for the detection of neutralizing antibodies against therapeutic angiotensin-converting enzyme 2 (ACE2)

2013 ◽  
Vol 389 (1-2) ◽  
pp. 52-60 ◽  
Author(s):  
Karen Liao ◽  
Daniel Sikkema ◽  
Catherine Wang ◽  
Thomas N. Lee
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Neutralizing Antibodies ◽  
Enzymatic Assay ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme 2

scholarly journals Amino acids 484 and 494 of SARS-CoV-2 spike are hotspots of immune evasion affecting antibody but not ACE2 binding

2021 ◽  
Author(s):  
Marta Alenquer ◽  
Filipe Ferreira ◽  
Diana Lousa ◽  
Mariana Valério ◽  
Mónica Medina-Lopes ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Angiotensin Converting Enzyme ◽  
Immune Evasion ◽  
Neutralizing Antibodies ◽  
Receptor Binding Domain ◽  
Converting Enzyme ◽  
Antibody Neutralization ◽  
Angiotensin Converting Enzyme 2 ◽  
The Core

AbstractUnderstanding SARS-CoV-2 evolution and host immunity is critical to control COVID-19 pandemics. At the core is an arms-race between SARS-CoV-2 antibody and angiotensin-converting enzyme 2 (ACE2) recognition, a function of the viral protein spike and, predominantly, of its receptor-binding-domain (RBD). Mutations in spike impacting antibody or ACE2 binding are known, but the effect of mutation synergy is less explored. We engineered 22 spike-pseudotyped lentiviruses containing individual and combined mutations, and confirmed that E484K evades antibody neutralization elicited by infection or vaccination, a capacity augmented when complemented by K417N and N501Y mutations. In silico analysis provided an explanation for E484K immune evasion. E484 frequently engages in interactions with antibodies but not with ACE2. Importantly, we identified a novel amino acid of concern, S494, which shares a similar pattern. Using the already circulating mutation S494P, we found that it reduces antibody neutralization of convalescent sera. This amino acid emerges as an additional hotspot for immune evasion and a target for therapies, vaccines and diagnostics.One-Sentence SummaryAmino acids in SARS-CoV-2 spike protein implicated in immune evasion are biased for binding to neutralizing antibodies but dispensable for binding the host receptor angiotensin-converting enzyme 2.

scholarly journals Angiotensin-Converting Enzyme 2 (ACE2) in the Pathogenesis of ARDS in COVID-19

2021 ◽  
Vol 12 ◽  
Author(s):  
Keiji Kuba ◽  
Tomokazu Yamaguchi ◽  
Josef M. Penninger
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Neutralizing Antibodies ◽  
Cell Entry ◽  
Converting Enzyme ◽  
Sars Coronavirus ◽  
Angiotensin Converting Enzyme 2 ◽  
Infected People ◽  
Critical Attention ◽  
Novel Coronavirus

Seventeen years after the epidemic of SARS coronavirus, a novel coronavirus SARS-CoV-2-emerged resulting in an unprecedented pandemic. Angiotensin-converting enzyme 2 (ACE2) is an essential receptor for cell entry of SARS-CoV-2 as well as the SARS coronavirus. Despite many similarities to SARS coronavirus, SARS-CoV-2 exhibits a higher affinity to ACE2 and shows higher infectivity and transmissibility, resulting in explosive increase of infected people and COVID-19 patients. Emergence of the variants harboring mutations in the receptor-binding domain of the Spike protein has drawn critical attention to the interaction between ACE2 and Spike and the efficacies of vaccines and neutralizing antibodies. ACE2 is a carboxypeptidase which degrades angiotensin II, B1-bradykinin, or apelin, and thereby is a critical regulator of cardiovascular physiology and pathology. In addition, the enzymatic activity of ACE2 is protective against acute respiratory distress syndrome (ARDS) caused by viral and non-viral pneumonias, aspiration, or sepsis. Upon infection, both SARS-CoV-2 and SARS coronaviruses downregulates ACE2 expression, likely associated with the pathogenesis of ARDS. Thus, ACE2 is not only the SARS-CoV-2 receptor but might also play an important role in multiple aspects of COVID-19 pathogenesis and possibly post-COVID-19 syndromes. Soluble forms of recombinant ACE2 are currently utilized as a pan-variant decoy to neutralize SARS-CoV-2 and a supplementation of ACE2 carboxypeptidase activity. Here, we review the role of ACE2 in the pathology of ARDS in COVID-19 and the potential application of recombinant ACE2 protein for treating COVID-19.

scholarly journals Mutations in two SARS-CoV-2 variants of concern reflect two distinct strategies of antibody escape

2021 ◽  
Author(s):  
Sebastian Fiedler ◽  
Viola Denninger ◽  
Alexey S. Morgunov ◽  
Alison Ilsley ◽  
Roland Worth ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Receptor Binding ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Cell Receptor ◽  
Converting Enzyme ◽  
Wild Type ◽  
Angiotensin Converting Enzyme 2 ◽  
Binding Domains ◽  
Host Cell Receptor

Understanding the factors that contribute to antibody escape of SARS-CoV-2 and its variants is key for the development of drugs and vaccines that provide broad protection against a variety of virus variants. Using microfluidic diffusional sizing, we determined the dissociation constant ((KD)) for the interaction between receptor binding domains (RBDs) of SARS-CoV-2 in its original version (WT) as well as alpha and beta variants with the host-cell receptor angiotensin converting enzyme 2 (ACE2). For RBD-alpha, the ACE2-binding affinity was increased by a factor of ten when compared with RBD-WT, while ACE2-binding of RBD-beta was largely unaffected. However, when challenged with a neutralizing antibody that binds to both RBD-WT and RBD-alpha with low nanomolar (KD) values, RBD-beta displayed no binding, suggesting a substantial epitope change. In SARS-CoV-2 convalescent sera, RBD-binding antibodies showed low nanomolar affinities to both wild-type and variant RBD proteins—strikingly, the concentration of antibodies binding to RBD-beta was half that of RBD-WT and RBD-alpha, again indicating considerable epitope changes in the beta variant. Our data therefore suggests that one factor contributing to the higher transmissibility and antibody evasion of SARS-CoV-2 alpha and beta is a larger fraction of viruses that can form a complex with ACE2. However, the two variants employ different mechanisms to achieve this goal. While SARS-CoV-2 alpha RBD binds with greater affinity to ACE2 and is thus more difficult to displace from the receptor by neutralizing antibodies, RBD-beta is less accessible to antibodies due to epitope changes which increases the chances of ACE2-binding and infection.

scholarly journals Antibodies to SARS-CoV-2 and their potential for therapeutic passive immunization

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
PJ Klasse ◽  
John P Moore
Keyword(s):  
Public Health ◽  
Monoclonal Antibodies ◽  
Antibody Response ◽  
Angiotensin Converting Enzyme ◽  
Causative Agent ◽  
Neutralizing Antibodies ◽  
Passive Immunization ◽  
Converting Enzyme ◽  
S Protein ◽  
Angiotensin Converting Enzyme 2

We review aspects of the antibody response to SARS-CoV-2, the causative agent of the COVID-19 pandemic. The topics we cover are relevant to immunotherapy with plasma from recovered patients, monoclonal antibodies against the viral S-protein, and soluble forms of the receptor for the virus, angiotensin converting enzyme 2. The development of vaccines against SARS-CoV-2, an essential public health tool, will also be informed by an understanding of the antibody response in infected patients. Although virus-neutralizing antibodies are likely to protect, antibodies could potentially trigger immunopathogenic events in SARS-CoV-2-infected patients or enhance infection. An awareness of these possibilities may benefit clinicians and the developers of antibody-based therapies and vaccines.

scholarly journals Structural Analysis of the Novel Variants of SARS-CoV-2 and Forecasting in North America

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 930
Author(s):  
Elena Quinonez ◽  
Majid Vahed ◽  
Abdolrazagh Hashemi Shahraki ◽  
Mehdi Mirsaeidi
Keyword(s):  
North America ◽  
Angiotensin Converting Enzyme ◽  
Neutralizing Antibodies ◽  
Herd Immunity ◽  
Neutralizing Antibody ◽  
The Novel ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme 2 ◽  
Global Database ◽  
Novel Variants

Background: little is known about the forecasting of new variants of SARS-COV-2 in North America and the interaction of variants with vaccine-derived neutralizing antibodies. Methods: the affinity scores of the spike receptor-binding domain (S-RBD) of B.1.1.7, B. 1.351, B.1.617, and P.1 variants in interaction with the neutralizing antibody (CV30 isolated from a patient), and human angiotensin-converting enzyme 2 (hACE2) receptor were predicted using the template-based computational modeling. From the Nextstrain global database, we identified prevalent mutations of S-RBD of SARS-CoV-2 from December 2019 to April 2021. Pre- and post-vaccination time series forecasting models were developed based on the prediction of neutralizing antibody affinity scores for S-RBD of the variants. Results: the proportion of the B.1.1.7 variant in North America is growing rapidly, but the rate will reduce due to high affinity (~90%) to the neutralizing antibody once herd immunity is reached. Currently, the rates of isolation of B. 1.351, B.1.617, and P.1 variants are slowly increasing in North America. Herd immunity is able to relatively control these variants due to their low affinity (~70%) to the neutralizing antibody. The S-RBD of B.1.617 has a 110% increased affinity score to the human angiotensin-converting enzyme 2 (hACE2) in comparison to the wild-type structure, making it highly infectious. Conclusion: The newly emerged B.1.351, B.1.617, and P.1 variants escape from vaccine-induced neutralizing immunity and continue circulating in North America in post- herd immunity era. Our study strongly suggests that a third dose of vaccine is urgently needed to cover novel variants with affinity scores (equal or less than 70%) to eliminate developing viral mutations and reduce transmission rates.

Thermodynamics of the interaction between the spike protein of severe acute respiratory syndrome- coronavirus-2 and the receptor of human angiotensin converting enzyme 2. Effects of possible ligands

2020 ◽  
Author(s):  
Cristina Garcia-Iriepa ◽  
Cecilia Hognon ◽  
Antonio Francés-Monerris ◽  
Isabel Iriepa ◽  
Tom Miclot ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Molecular Mechanisms ◽  
Molecular Design ◽  
Binding Free Energy ◽  
Transmembrane Protein ◽  
Spike Protein ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme 2 ◽  
Rational Molecular Design ◽  
Rational Evaluation

<div><p>Since the end of 2019, the coronavirus SARS-CoV-2 has caused more than 180,000 deaths all over the world, still lacking a medical treatment despite the concerns of the whole scientific community. Human Angiotensin-Converting Enzyme 2 (ACE2) was recently recognized as the transmembrane protein serving as SARS-CoV-2 entry point into cells, thus constituting the first biomolecular event leading to COVID-19 disease. Here, by means of a state-of-the-art computational approach, we propose a rational evaluation of the molecular mechanisms behind the formation of the complex and of the effects of possible ligands. Moreover, binding free energy between ACE2 and the active Receptor Binding Domain (RBD) of the SARS-CoV-2 spike protein is evaluated quantitatively, assessing the molecular mechanisms at the basis of the recognition and the ligand-induced decreased affinity. These results boost the knowledge on the molecular grounds of the SARS-CoV-2 infection and allow to suggest rationales useful for the subsequent rational molecular design to treat severe COVID-19 cases.</p></div>

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