As experts continue to warn that ignoring COVID-19 and the 15,000 deaths a day it is causing is a grave mistake, it has become clear a lasting solution to the virus will require something that neutralizes all coronavirus variants, else we risk constantly trailing behind. Now, Harvard researchers believe they have found just that – a single antibody that neutralizes all known SARS-CoV-2 variants in their laboratory tests.
The antibody could be used within existing vaccination strategies to finally put an end to the constant cycle, should the results transfer well to human trials. The findings were published in Science Immunology.
“We hope this antibody will prove to be as effective in patients as it has been in preclinical evaluations thus far,” said Frederick Alt, the HMS Charles A. Janeway Professor of Pediatrics at Boston Children’s and a senior investigator on the study, in a statement.
“If it does, it might provide a new therapeutic and also contribute to new vaccine strategies.”
To create a broad-spectrum antibody across multiple variants, the researchers turned to mouse models that were previously created for HIV research. These mice have been turned into models of our own immune system, identifying foreign pathogens and going through the same trial-and-error motions to create antibodies that neutralize them. This way, the mice are essentially mini machines that can efficiently provide new antibodies for use in therapeutics.
When exposed to the original SARS-CoV-2 strain first identified in Wuhan, the mouse models created nine different types of antibodies that could bind to the virus, though not all neutralized it. Further tests identified three of these were able to strongly neutralize the original strain, but one, called SP1-77, was even more impressive – it could also neutralize alpha, beta, delta, gamma, and most importantly, omicron variants.
But how is it able to stop the virus when its spike proteins look different due to their various mutations? SP1-77 doesn’t act on the same regions as many other antibodies, instead opting for a region that has not yet mutated in any SARS-CoV-2.
“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, professor of cell biology at the Blavatnik Institute at HMS.
“These properties may contribute to its broad and potent activity.”
The researchers have now applied for patents and hope the work can be produced commercially, once the results are verified in human trials.