T cells DO still hold up against Omicron, study proves

T cells DO still hold up against Omicron, study proves

January 4, 2022

More ‘good news’ in the fight against Omicron: Crucial T cells DO still hold up against ultra-infectious variant, study proves

  • Researchers analysed if T-cells were still able to recognise and attack Omicron
  • Scientists say the findings are positive news for the global fight against Covid
  • T cell response generated by Covid jabs should still target  new Covid variant
  • While Omicron can dodge antibodies, T cells will help prevent serious illness 

Omicron can be thwarted by another part of the immune system, research today confirmed.

Dozens of studies have shown the extremely-infectious variant is better at evading antibodies, which sparked fears the protection offered by vaccines and prior infection would evaporate. 

However, virologists have repeatedly insisted that T cells — a key secondary part of the body’s natural defence — can prevent people becoming from severely ill with Omicron. 

Now laboratory tests have verified the claims, bolstering the the argument Omicron generally only results in a very mild illness thanks to the protection offered by vaccines.

Professor Matthew McKay, a researcher at the University of Melbourne who carried out the research, described it as ‘positive news’.

He said: ‘Even if Omicron — or some other variant for that matter — can potentially escape antibodies, a robust T-cell response can still be expected to offer protection and help to prevent significant illness.

This chart shows how many spike proteins epitopes a type of T-cell called CD8 might be unable to target due to mutations, by Covid strain. While this is higher for Omicron (far right bar) 86 per cent were unaffected meaning a significant and robust T-cell response was likely

Similar findings were found for the spike proteins epitopes another type of T-cell called CD4 might be unable to target due to mutations, by Covid strain. While this is higher for Omicron (far right bar) 72 per cent were unaffected and therefore, a significant and robust T-cell response was likely

There are hopes that the Omicron outbreak in London, the epicentre of the UK’s outbreak has started to peak as hosplisations in the capital have begun to fall

‘Based on our data, we anticipate T-cell responses elicited by vaccines and boosters will continue to help protect against Omicron, as observed for other variants. 

‘We believe this presents some positive news in the global fight against Omicron.’

The findings add to a growing plethora of research supporting how jabs are helping prevent the majority of people becoming severely ill.  

T cells which are more difficult to measure than antibodies, are thought to provide longer-lasting protection.

The cells, which are a type of white blood cell grown in bone marrow work to kill other cells infected by a virus when it is already in the in the body, stopping the infection from spreading. 

How well T cells identify a virus can spell the difference between a mild infection with cold-like symptoms and requiring hospital care.   

In comparison to T cells antibodies work to stop a virus from taking hold in the body in the first place. But if this initial protection fails other parts of the body’s immune system come into play. 

This is particularly important as antibody levels are known to wane over time, be that from getting a vaccine or a prior infection, leading to reinfection or what is known as a breakthrough case. 

Covid vaccines have been designed to generate antibodies in order to stop people getting the virus and passing it on to others, breaking the chains of transmission.  

But studies have shown the antibodies made by the currently available jabs, and those created by non-Omicron Covid are less effective the new variant.  

This is because the strain has an abundance of mutations it its spike protein, the primary target of the vaccines. This spike is what enables the virus to attach and enter cells in humans.

The research, from the University of Melbourne and Hong Kong University of Science and Technology, analysed 1,500 fragments of Covid viral proteins – called epitopes.

When they examined 391 Covid spike protein epitopes which are targeted by the T cells vaccinated or previously infected individuals the study found that only 20 per cent showed mutations associated with Omicron.  

This they argue indicates that the T cells should still provide a strong response against Omicron, or any other variant. 

Hong Kong University of Science and Technology’s Professor Ahmed Abdul Quadeer, study co-author, said: ‘Among T-cell epitopes with Omicron mutations, our analysis revealed more than half are predicted to still be visible to T-cells.

‘This further diminishes the chance that Omicron may escape T-cells’ defenses.’  

Results were published in the peer-reviewed journal Viruses.

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