Analyzing blood samples, the team from the La Jolla Institute for Immunology (LJI) in California, US, found that people who experienced symptomatic breakthrough infections from the Delta and Omicron variants developed T-cells that fight SARS-CoV-2. Are better able to identify and target. -2.
Professor Alessandro Sette of LJI said, "The virus evolves, but importantly, the immune system also evolves. T-cells do not sit idle. Instead, they learn to recognize parts of the virus that mutate. Are."
The researchers noted that due to multiple infections, "cells can recognize multiple features, or antigens, on SARS-CoV-2." As a result, the volunteers' T-cells could recognize and target SARS-CoV-2, "even if some part of me was mutated."
The study, published in the journal Cell Reports Medicine, showed that prior asymptomatic infections boosted T-cell responses, however, the effect was not as significant.
Additionally, successful infections also induced B-cells to produce cross-reactive antibodies against SARS-CoV-2. Most of these antibodies targeted the new virus variants and the original vaccine antigens.
“New B-cell responses that are specific only to the infected variant, but not the vaccine, are very rare,” said LJI instructor Parham Ramezani-Rad.,
Importantly, the researchers discovered that successful infections add more layers of protection to a person “on top of the vaccine.”
Covid vaccines are given in the upper arm, which means virus-fighting immune cells develop far away from the upper respiratory system.
But, SARS-CoV-2 first infects the upper respiratory tract, which means there may be a delay in getting the right immune cells to the site of infection, preventing infection, the researchers explained.
The researchers found no evidence of harmful “T-cell exhaustion,” where T-cells lose their ability to target the pathogen after repeated infections.
Professor Alessandro Sette of LJI said, "The virus evolves, but importantly, the immune system also evolves. T-cells do not sit idle. Instead, they learn to recognize parts of the virus that mutate. Are."
The researchers noted that due to multiple infections, "cells can recognize multiple features, or antigens, on SARS-CoV-2." As a result, the volunteers' T-cells could recognize and target SARS-CoV-2, "even if some part of me was mutated."
The study, published in the journal Cell Reports Medicine, showed that prior asymptomatic infections boosted T-cell responses, however, the effect was not as significant.
Additionally, successful infections also induced B-cells to produce cross-reactive antibodies against SARS-CoV-2. Most of these antibodies targeted the new virus variants and the original vaccine antigens.
“New B-cell responses that are specific only to the infected variant, but not the vaccine, are very rare,” said LJI instructor Parham Ramezani-Rad.,
Importantly, the researchers discovered that successful infections add more layers of protection to a person “on top of the vaccine.”
Covid vaccines are given in the upper arm, which means virus-fighting immune cells develop far away from the upper respiratory system.
But, SARS-CoV-2 first infects the upper respiratory tract, which means there may be a delay in getting the right immune cells to the site of infection, preventing infection, the researchers explained.
The researchers found no evidence of harmful “T-cell exhaustion,” where T-cells lose their ability to target the pathogen after repeated infections.
