Scientists Isolate Smallest Biological Molecule to Date That Completely and Specifically Neutralizes SARS-CoV-2
By HospiMedica International staff writers Posted on 15 Sep 2020 |
Illustration
Scientists at the University of Pittsburgh School of Medicine (Pittsburgh, PA, USA) have isolated the smallest biological molecule to date that completely and specifically neutralizes the SARS-CoV-2 virus.
The antibody component, which is 10 times smaller than a full-sized antibody, has been used to construct a drug - known as Ab8 - for potential use as a therapeutic and prophylactic against SARS-CoV-2. The tiny antibody component is the variable, heavy chain (VH) domain of an immunoglobulin, which is a type of antibody found in the blood. It was found by “fishing” in a pool of more than 100 billion potential candidates using the SARS-CoV-2 spike protein as bait. Ab8 is created when the VH domain is fused to part of the immunoglobulin tail region, adding the immune functions of a full-size antibody without the bulk.
According to the researchers, Ab8 is highly effective in preventing and treating SARS-CoV-2 infection in mice and hamsters. Its tiny size not only increases its potential for diffusion in tissues to better neutralize the virus, but also makes it possible to administer the drug by alternative routes, including inhalation. Importantly, it does not bind to human cells - a good sign that it will not have negative side-effects in people. The researchers believe that its small size could allow Ab8 to be administered as an inhaled drug or intradermally, rather than intravenously through an IV drip, like most monoclonal antibodies currently in development.
Researchers who tested Ab8 using live SARS-CoV-2 virus found that at very low concentrations, Ab8 completely blocked the virus from entering cells. The tem further tested Ab8 at varying concentrations in mice using a modified version of SARS-CoV-2 and found that even at the lowest dose, Ab8 decreased by 10-fold the amount of infectious virus in those mice compared to their untreated counterparts. Ab8 was also effective in treating and preventing SARS-CoV-2 infection in hamsters.
“Ab8 not only has potential as therapy for COVID-19, but it also could be used to keep people from getting SARS-CoV-2 infections,” said co-author John Mellors, M.D., chief of the Division of Infectious Diseases at UPMC and Pitt. “Antibodies of larger size have worked against other infectious diseases and have been well tolerated, giving us hope that it could be an effective treatment for patients with COVID-19 and for protection of those who have never had the infection and are not immune.”
Related Links:
University of Pittsburgh School of Medicine
The antibody component, which is 10 times smaller than a full-sized antibody, has been used to construct a drug - known as Ab8 - for potential use as a therapeutic and prophylactic against SARS-CoV-2. The tiny antibody component is the variable, heavy chain (VH) domain of an immunoglobulin, which is a type of antibody found in the blood. It was found by “fishing” in a pool of more than 100 billion potential candidates using the SARS-CoV-2 spike protein as bait. Ab8 is created when the VH domain is fused to part of the immunoglobulin tail region, adding the immune functions of a full-size antibody without the bulk.
According to the researchers, Ab8 is highly effective in preventing and treating SARS-CoV-2 infection in mice and hamsters. Its tiny size not only increases its potential for diffusion in tissues to better neutralize the virus, but also makes it possible to administer the drug by alternative routes, including inhalation. Importantly, it does not bind to human cells - a good sign that it will not have negative side-effects in people. The researchers believe that its small size could allow Ab8 to be administered as an inhaled drug or intradermally, rather than intravenously through an IV drip, like most monoclonal antibodies currently in development.
Researchers who tested Ab8 using live SARS-CoV-2 virus found that at very low concentrations, Ab8 completely blocked the virus from entering cells. The tem further tested Ab8 at varying concentrations in mice using a modified version of SARS-CoV-2 and found that even at the lowest dose, Ab8 decreased by 10-fold the amount of infectious virus in those mice compared to their untreated counterparts. Ab8 was also effective in treating and preventing SARS-CoV-2 infection in hamsters.
“Ab8 not only has potential as therapy for COVID-19, but it also could be used to keep people from getting SARS-CoV-2 infections,” said co-author John Mellors, M.D., chief of the Division of Infectious Diseases at UPMC and Pitt. “Antibodies of larger size have worked against other infectious diseases and have been well tolerated, giving us hope that it could be an effective treatment for patients with COVID-19 and for protection of those who have never had the infection and are not immune.”
Related Links:
University of Pittsburgh School of Medicine
Latest COVID-19 News
- Low-Cost System Detects SARS-CoV-2 Virus in Hospital Air Using High-Tech Bubbles
- World's First Inhalable COVID-19 Vaccine Approved in China
- COVID-19 Vaccine Patch Fights SARS-CoV-2 Variants Better than Needles
- Blood Viscosity Testing Can Predict Risk of Death in Hospitalized COVID-19 Patients
- ‘Covid Computer’ Uses AI to Detect COVID-19 from Chest CT Scans
- MRI Lung-Imaging Technique Shows Cause of Long-COVID Symptoms
- Chest CT Scans of COVID-19 Patients Could Help Distinguish Between SARS-CoV-2 Variants
- Specialized MRI Detects Lung Abnormalities in Non-Hospitalized Long COVID Patients
- AI Algorithm Identifies Hospitalized Patients at Highest Risk of Dying From COVID-19
- Sweat Sensor Detects Key Biomarkers That Provide Early Warning of COVID-19 and Flu
- Study Assesses Impact of COVID-19 on Ventilation/Perfusion Scintigraphy
- CT Imaging Study Finds Vaccination Reduces Risk of COVID-19 Associated Pulmonary Embolism
- Third Day in Hospital a ‘Tipping Point’ in Severity of COVID-19 Pneumonia
- Longer Interval Between COVID-19 Vaccines Generates Up to Nine Times as Many Antibodies
- AI Model for Monitoring COVID-19 Predicts Mortality Within First 30 Days of Admission
- AI Predicts COVID Prognosis at Near-Expert Level Based Off CT Scans