As new research shows, there is another “good news” in the fight against the Omicron coronavirus: key T cells really resist the ultra-infectious variants of COVID-19. Scientists who analyzed whether T cells are able to recognize and attack Omicron claim that the data obtained is positive news for the global fight against COVID.
While Omicron can avoid antibodies, T cells help prevent serious diseases. New research has confirmed that another part of the immune system can interfere with the new variant of COVID.
As he writes Daily Mail, dozens of studies have shown that the extremely contagious variant of coronavirus avoids antibodies better – and this has raised fears that the protection provided by vaccines and previous infection will disappear. However, virologists have repeatedly insisted that T-cells (a key secondary part of the body’s natural defense) can prevent people from becoming seriously ill due to Omicron, even if people are still infected.
Now laboratory tests have confirmed the claims that Omicron tends to cause only very mild diseases.
Professor Matthew McKay, a researcher at the University of Melbourne who conducted the study, called it “positive news.” He says: “Even if Omicron – or some other option for that matter – could potentially elude antibodies, a sustained T-cell response could be expected to provide protection and help prevent serious diseases. Based on our data, we expect that T-cell responses induced by vaccines and boosters will continue to contribute to protection against Omicron, as is observed for other variants. We believe that this provides some positive news in the global fight against Omicron.”
The findings complement a growing body of research confirming how vaccinations help prevent severe illness in most people.
It is believed that T cells, which are harder to measure than antibodies, provide longer-lasting protection. The cells, which are a type of white blood cells grown in the bone marrow, prevent infection from multiplying, causing severe disease in the body. They can mean the difference between a person suffering from cold symptoms and needing hospital treatment.
Compared to T cells, antibodies primarily prevent the spread of the virus. But if this initial defense fails, other parts of the immune system may come into play. This is especially important because it is known that antibody levels decrease over time, whether as a result of vaccination or a previous infection leading to re-infection or a so-called “breakthrough” case.
COVID vaccines were developed to produce antibodies so that people could not get the virus and not pass it on to others by breaking the transmission chains. But studies have shown that antibodies produced by currently available vaccinations and antibodies created by other COVID variants (not Omicron) are less effective with the new variant. This is due to the fact that this strain has many mutations in its spike protein, which is the main target of vaccines. This spike allows the virus to attach and penetrate into human cells.
In a study conducted by the University of Melbourne and the Hong Kong University of Science and Technology, 1,500 fragments of COVID viral proteins, called epitopes, were analyzed. Only 20 percent of the epitopes targeted by T cells showed mutations associated with Omicron.
This, according to scientists, indicates that T cells still need to provide a strong response against Omicron or any other variant of COVID.
Ahmed Abdul Quadir, a professor at the Hong Kong University of Science and Technology, co-author of the study, says: “Among the T-cell epitopes with Omicron mutations, our analysis showed that more than half, according to forecasts, are still visible to T cells. This further reduces the likelihood that Omicron will be able to avoid protection from T cells.”
