Omicron COVID-19 Variant: Why Antibodies Become Ineffective Against The New Strain Of Coronavirus?

The Omicron variant has become the dominant variant around the world, primarily so because it escapes antibodies. Know why antibodies become ineffective against the new COVID variant.

Omicron, the new variant of COVID-19, has become the dominant strain around the world. The new variant of COVID-19, which was first discovered in South Africa, is the virus's most mutated version, with over 50 changes, 30 of which are in its spike protein, allowing it to bypass vaccine-induced immunity. Omicron has begun infecting people across India. At a time when the country is still reeling from the trauma caused by the second wave of coronavirus that ravaged the world throughout 2021, the arrival of this new variant serves as a stark reminder that COVID-19 is still here. What's more concerning is that the variant is more transmissible than the previous variants. However, it is milder in nature.

Why Antibodies Become Ineffective Against Omicron?

Antibodies against the Omicron variant of Covid-19 are ineffective due to the existence of a huge number of mutations, including more than 30 on its spike protein, according to a study published in the Journal of Autoimmunity. An extraordinary number of mutations, particularly in the Spike (S) protein of the Omicron strain, have been linked to its high transmissibility and infectivity.

These modifications also enable it to resist pre-existing antibodies in the human body, which contributes to an increasing number of re-infections and breakthrough cases. The University of Missouri researchers wanted to learn more about the alterations detected in the Omicron variant's S-protein.

The study detected 46 hallmark changes within the Omicron variant using full sequences, 23 of which were wholly new and had not been identified in any of the previous variants of the virus. Two of the mutations were discovered in the Delta or Delta Plus variant first. Thirty of the 46 changes were found in the S-protein, while the rest were found elsewhere in the viral cell. Furthermore, the researchers employed a pre-existing S-protein structure to see if the Omicron mutations would damage the Covid-19 S-protein in the same way, rendering antibodies ineffective.

Certain Mutations May Affect Protection Against Omicron

According to the paper, certain mutations cause interference on the virus's surface, preventing antibodies from adhering to it, while others result in a complete loss of interaction between the antibodies and the virus, rendering the antibodies useless against the highly modified variety. According to the researchers, this shows that pre-existing immunity (whether from vaccination or past infection) may no longer be able to give adequate protection against the Omicron form of the virus, allowing it to evade antibodies and penetrate the immune system.

Kamlendra Singh, a professor at the university's College of Veterinary Medicine said, "The purpose of antibodies is to recognise the virus and stop the binding, which prevents infection."

"However, we found many of the mutations in the Omicron variant are located right where the antibodies are supposed to bind, so we are showing how the virus continues to evolve in a way that it can potentially escape or evade the existing antibodies, and therefore continue to infect so many people," he added.

(with inputs from agencies)