Though only in early stages, findings could lead to a ‘therapeutic against current and newly-arising variants,’ say researchers
As SARS-CoV-2 changes and mutates, some therapeutic antibodies that were once highly effective in fighting the virus have lost potency. But now, in a proof-of-concept study, researchers from Boston Children’s Hospital have identified one antibody that neutralizes all known variants of the coronavirus, including the omicron variant. Microbiologists and clinical laboratory managers will find this intriguing, as most medical labs perform serology testing for SARS-CoV-2 antibodies.
The new antibody appears to be robust. It triggers several other types of antibodies as part of the immune response. If validated by further research, this discovery, the researchers state, may lead to new vaccines, better therapies, and improved treatments for COVID-19.
The scientists published their findings in the journal Science Immunology, titled, “An Antibody from Single Human VH-rearranging Mouse Neutralizes All SARS-CoV-2 Variants Through BA.5 by Inhibiting Membrane Fusion.”
“We hope that this humanized antibody will prove to be as effective at neutralizing SARS-CoV-2 in patients as it has proven to be thus far in preclinical evaluations,” said geneticist Frederick Alt, PhD, Director of the Program in Cellular and Molecular Medicine at Boston Children’s Hospital and one of the leaders of the research. Clinical laboratories that perform serology testing for COVID-19 will be intrigued by this new line of research. (Photo copyright: PR Newswire.)
SP1-77 Antibody Outperforms All Others at Neutralizing SARS-CoV-2
To conduct their research, the team used genetically modified mice that basically have built-in human immune systems. These mice were originally utilized for seeking out antibodies to HIV, another virus that tends to mutate. Their immune systems can mimic what human immune systems encounter when a viral invader attacks.
The scientists inserted two human gene segments into the mice, which quickly produced antibodies resembling those made by humans. The mice were then exposed to the SARS-CoV-2 spike protein from the original coronavirus strain. The scientists found that the mice produced nine different families of antibodies that could bind to the spike protein.
The researchers then tested the effectiveness of those antibodies and found that three of the nine antibody families strongly neutralized the original SARS-CoV-2 coronavirus. In addition, one of the antibody families—dubbed SP1-77—was much more powerful and could neutralize the Alpha, Beta, Gamma, Delta, and all known Omicron strains of the SARS-CoV-2 virus.
New Monoclonal Antibody Products and Vaccines
If their findings are validated through further research, SP1-77 “would have potential to be a therapeutic against current and newly-arising variants of concern” according to the Science Immunology study. It also could be useful as part of a cocktail containing other antibody treatments for COVID-19 variants.
“SP1-77 binds the spike protein at a site that so far has not been mutated in any variant, and it neutralizes these variants by a novel mechanism,” said Tomas Kirchhausen, PhD, Senior Investigator, Program in Cellular and Molecular Medicine at Boston Children’s Hospital and one of the authors of the study in a statement announcing the study findings. “These properties may contribute to its broad and potent activity,” he added.
“This is very early-stage proof-of-concept work to illustrate that broadly neutralizing antibodies can be generated using a mouse model,” Amesh Adalja, MD, an infectious disease expert and senior scholar at the Johns Hopkins Center for Health Security, told Prevention. “Such work, if replicated and expanded, could form the basis of new monoclonal antibody products as well as a vaccine.”
The researchers have applied for a patent for the SP1-77 antibody as well as the mouse model they used to create it. Studies on the antibody are ongoing and have only been performed on mice and not humans. The scientists intend to execute further research on the innovative antibody and hope it will someday be used to help fight the COVID-19 virus and all its variants.
“We’d love to have a vaccine that is active against all circulating variants, including those yet to come,” Thomas Russo, MD, Professor and Chief of Infectious Disease, Department of Medicine, University at Buffalo told Prevention. “It’s the holy grail of vaccines.”
Microbiologists and clinical laboratories working with monoclonal antibodies to treat for COVID-19 infections will no doubt want to follow the Boston Children’s Hospital research closely as it may lead to new treatments and vaccines.