Omicron: Explainer: T-cells guard against Omicron as antibodies fail

New Delhi: Amid rising cases Covid-19 And its new types, OmicronAround the world, experts warn that the newer and more widely considered infectious variant is likely to soon replace Delta as the dominant global type, which has a virus fitter and has reproductive benefits.
While the delta is still the most common type on all continents except Africa, Omicron spreads very quickly. Even people with a complete vaccine without a travel history have tested positive for Omicron, which casts doubt on the effectiveness of the existing Covid-19 vaccine, discusses the need for a booster dose, and speculates on a third wave.
As mutations in omikron are said to be able to help the body’s first line of defense, antibodies, survive, studies have highlighted a major role that T-cells, the second line of defense of the immune system, may play. T cells, the body’s weapon against virus-infected cells, were primed enough by vaccination that they protect against omicron, a separate study found.
What are T-cells?
T-cells are white blood cells that can remember past diseases, attack virus-infected cells, or help produce antibodies to fight them. Unlike antibodies, T-cells can target the spike protein of the whole virus, which remains largely the same even in highly mutated omikron.
T cells are extremely effective in identifying and attacking the omicron variant, which prevents most infections from progressing to serious illness, a study shows.
‘T’ stands for thymus, the organ in which the final stage of cell development takes place.

Take the researchers

A study by the Institute of Infectious Diseases and Molecular Medicine at the University of Cape Town, which looked at patients who had recovered from covid or had been vaccinated, found that they evaluated 70% to 80% of T-cell responses against omicron.
“Most T-cell responses, induced by vaccination or natural infection, recognize diversity, despite extensive mutations in omicron and reduced susceptibility to inactivation of antibodies,” the researchers said.
In another study, researchers Erasmus University In the Netherlands, 60 vaccinated healthcare workers were observed and found that while their antibody responses to Omicron were low or non-existent compared to beta and delta variants, T-cell responses were largely unchanged, “inhibiting antibodies to inhibit or inactivate antibodies.” Limit the serious Covid-19. ”
In test tube experiments, in researchers South Africa Volunteers receiving vaccines from Johnson & Johnson or Pfizer / Bioentech exposed copies of the virus in T-cells or who were not vaccinated but developed their own T-cells after infection with an earlier version of the coronavirus.
“Most T-cell responses, induced by vaccination or natural infection, recognize diversity, despite extensive mutations in omicron and reduced sensitivity to inactivating antibodies,” the researchers say.
“The well-preserved T-cell immunity for Omicron is likely to contribute to protection against severe Covid-19,” said South African doctors, who initially suspected that most patients with Omicron infection were not seriously ill.


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