The immune cells of people who received Covid 19 vaccines and also experienced “breakthrough” or repeated infections can build an “immunity wall” against future SARS-CoV-2 infections, according to scientists.
Analysing blood samples, the team at 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 are better at recognising and targeting SARS-CoV-2.
“The virus evolves, but, importantly, so does the immune system. T-cells do not sit idle. Instead, they learn to recognise the parts of the virus that mutate,” said Alessandro Sette, Professor at LJI.
The researchers noted that due to multiple infections, “the cells could recognise multiple features, or antigens, on SARS-CoV-2.” As a result, the volunteers’ T-cells could recognise and target SARS-CoV-2, “even if part of it was mutated.”
The study published in the journal Cell Reports Medicine showed that even asymptomatic breakthrough infections boost T-cell responses, however, the effect was not as significant.