A Surrogate Cell-Based Corona Virus Spike Protein Blocking Assay

Simple SummaryContent extracted from patent full text and abstract with AI.

This patent describes a cell-based assay system for quickly, safely, and affordably measuring the ability of antibodies or other compounds to block the interaction between the SARS-CoV-2 (coronavirus) spike protein and its human cell receptor (ACE-2). The method uses human cells engineered to express the spike protein in its native form, which are then allowed to bind to surfaces coated with ACE-2. If a tested antibody or compound successfully blocks this binding, it can be detected using a simple dye stain measured with standard lab equipment. This system is designed to work under basic laboratory safety conditions and can be rapidly adapted to new virus variants or other viruses.

Use CasesContent extracted from patent full text and abstract with AI.

• Screening and validating neutralizing antibodies for COVID-19 therapies or vaccines.
• Testing blood samples from patients or vaccinated individuals to assess their immune response and presence of blocking antibodies.
• Studying the effectiveness of antibodies or compounds against emerging SARS-CoV-2 variants.
• Developing and optimizing new therapeutic anti-viral antibodies or small molecules.
• Use in diagnostic laboratories for rapid, large-scale antibody testing and surveillance.
• Testing patient sera to monitor immunity longevity after infection or vaccination.
• Adapting the system to other viruses with known surface protein and receptor interactions (e.g., HIV, MERS) for similar antibody or compound screening.

BenefitsContent extracted from patent full text and abstract with AI.

• Does not require the use of live virus or high-containment biosafety laboratories (BSL2/BSL3), significantly increasing safety and accessibility.
• Fast and inexpensive compared to traditional neutralization tests, enabling large-scale or routine testing.
• Detects blocking antibodies against the native form of the spike protein, increasing accuracy and biological relevance.
• Flexible and rapidly adaptable to test antibodies or sera against emerging viral variants or other viruses.
• Uses common laboratory equipment and inexpensive reagents, facilitating widespread adoption, including in resource-limited settings.
• Enables high comparability between laboratories due to standardized reagents and protocols.
• Can be used to pre-screen and validate the effectiveness of new therapeutic antibodies before clinical application.

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Inventors & Applicants

Patent Abstract

To monitor infection by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and successful vaccination against coronavirus disease 2019 (COVID-19), the kinetics of neutralizing or blocking anti-SARS-CoV-2 antibody titers need to be assessed. Here, we report the development of a quick and inexpensive surrogate SARS-CoV-2 blocking assay (SUBA) using immobilized recombinant human ACE-2 (hACE-2, ACE-2) and human cells expressing the native form of surface SARS-CoV-2 spike protein. Spike protein-expressing cells bound to hACE-2 in the absence or presence of blocking antibodies were quantified by measuring the optical density of cell-associated crystal violet in a spectrophotometer. The advantages are that SUBA is a fast and inexpensive assay which does not require biosafety level 2- or 3-approved laboratories. Most importantly, SUBA detects blocking antibodies against the native trimeric cell-bound SARS-CoV-2 spike protein and can quickly be adjusted to quickly pre-screen already approved therapeutic antibodies or sera from vaccinated individuals for their ACE-2 blocking activities against any emerging SARS-CoV-2 variants.