As the Omicron COVID-19 variant continues to push a rise in cases across Canada, scientists at the University of British Columbia (UBC) have revealed the first in-depth analysis of the structure of the variant鈥檚 spike protein.
In a study currently in pre-print and under peer-review, researchers used cryo-electron microscopy to analyze the variant at near atomic resolution, according to a news release, which shows how the 鈥渉eavily mutated鈥 Omicron variant infects human cells and is 鈥渉ighly evasive of immunity.鈥
Cryo-electron microscopy involves flash-freezing the study subject and then bombarding them with electrons to produce microscope images of individual molecules. Those are then used to reconstruct the structure of the subject in minute detail.
鈥淭he Omicron variant is unprecedented for having 37 spike protein mutations, that鈥檚 three to five times more mutations than any other variant we鈥檝e seen,鈥 said UBC department of biochemistry and molecular biology professor Dr. Sriram Subramaniam
Subramaniam said analysis of the spike protein was important because the spike is how the virus attaches and infects human cells, and is also where antibodies attach to neutralize the virus.
鈥淪mall mutations on the spike protein have potentially big implications for how the virus is transmitted, how our body fights it off and the effectiveness of treatments,鈥 he said.
The study results show that several mutations in the spike protein have created new 鈥渟alt bridges鈥 and hydrogen bonds between the Omicron spike protein and the human cell receptor known as ACE2. These mutations appear to increase the binding strength of the virus.
Researcher鈥檚 findings show that Omicron has a much greater binding affinity than the original SARS-CoV-2 virus, with levels more comparable to the Delta variant.
Characteristics of the Omicron mutations likely contribute to the increased transmissibility of the variant, researchers wrote.
Subramaniam said the study confirms what other scientists are detecting in real-time worldwide, that the Omicron spike protein is 鈥渇ar better鈥 than other COVID-19 variants at evading monoclonal antibodies, as well as evading immunity produced by both vaccines and natural infection.
鈥淣otably, Omicron was less evasive of the immunity created by vaccines compared to the immunity stemming from natural infection in unvaccinated COVID-19 patients,鈥 he said. 鈥淭his suggests that vaccination remains our best defence against the Omicron variant.鈥
Subramaniam said the study shows the path forward on how to develop more effective treatments against the Omicron variant and any others that develop in the future.
鈥淯nderstanding how the virus attaches to and infects human cells means we can develop treatments that disrupt that process and neutralize the virus,鈥 he said.
