An unsung arm of the immune system appears to protect against serious illness with the omicron variant, even when antibodies are depleted, which helps explain why a record wave of infections has not engulfed hospitals so far.
T cells, the body’s weapon against virus-infected cells, were primed enough by vaccination to defend against the omicron in separate studies from the University of Erasmus in the Netherlands and the University of Cape Town in South Africa.
The results may help explain why the wave of omicron cases has not so far caused an increase in mortality from South Africa to the United States and the United Kingdom. the highly mutated omicron.
The Dutch researchers examined 60 vaccinated healthcare professionals and found that while their antibody responses to omicron were lower or non-existent compared to the beta and delta variants, T cell responses were largely unchanged, “potentially balancing the lack of neutralizing antibodies to prevent or severely limit Covid-19. “
The study from the University of Cape Town’s Institute of Infectious Disease and Molecular Medicine looked at patients who had recovered from Covid or had been vaccinated with shots from Pfizer Inc. and partner BioNTech SE or Johnson & Johnson. They found that 70% to 80% of the T cell responses they assessed were up against omicron.
Our T cells appear to be clear, willing and able to defend vs Omicron https://t.co/VA2AZW3Jhl CD4 + and CD8 + cells hold up well in people who have been vaccinated or previously Covid pic.twitter.com/nK9l63vDSA
– Eric Topol (@EricTopol) December 29, 2021
Recent weeks have brought evidence that the new strain can erode vaccine protection, prompting governments to push for booster shots to raise the level of antibodies that can combat the variant.
But immune protection has several layers. While antibodies block infection, T cells kill infected cells, preventing the virus from spreading and causing worse disease, wrote Wendy Burgens, one of the study authors at the University of Cape Town, on her Twitter account Virus Monologues. “They can not prevent you from getting infected, but they can minimize the damage that comes afterwards,” she said.
T cells are white blood cells that can remember previous diseases, kill virus-infected cells, and evoke antibodies against marshal defense. For example, humans infected with another coronavirus responsible for the SARS outbreak in 2003 were found to still have a T cell response to the disease 17 years later.
Another study showed that booster shots increased the production of T cells in light of an omicron infection. Giving J & J’s vaccine to people who had previously received a messenger RNA shot gave better results, although a third dose of Pfizer and BioNTech’s immunization also led to higher levels of cellular immunity and neutralizing antibodies after one month, according to results from Beth Israel Deaconess Medical Center.
(With the exception of the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)