The strong reaction caused by innate immunity does not last long
Children can easily defeat the novel coronavirus infection (Corona 19) by generating a strong initial response through their natural innate immunity, that is, the innate immune system, to quickly eliminate the virus.
However, researchers from the Australian Institute of Gastronomy found that this strong initial response is quickly halted, leaving the child’s immune system unable to remember the virus and prepare for future infections.
Dr. Trypan, who heads the biomicroscopy and gene expression lab, said: “Children are adept at getting rid of the virus the first time they are exposed to it, but when they are exposed to the virus a second time, they have adaptations that can act as protection. It turns out there is no chance of getting immunity.”
Everyone’s immune system has two modes: the innate system and the adaptive system. The innate immune system, which is naturally innate from parents, mainly consists of barriers such as skin and mucosal surfaces that physically block viruses from entering the body. It also cannot distinguish specific pathogens, but detecting foreign invaders such as viruses or bacteria can trigger a general immune response.
On the other hand, the adaptive immune system includes B and T cells that act as ‘memory’ cells. The system can learn to recognize and discriminate between different parts of a particular virus, and generate rapid, targeted responses to infection.
A baby’s immune system starts off blank and relies on the innate immune system to fight infection. And as they grow and are exposed to more viruses, memory T cells learn how to respond to those viruses.
Dr. Philip Britton (Pediatric Infectious Diseases) at Westmead Children’s Hospital Sydney, Australia, who participated in the study, said: “The child’s immune system moves from relying primarily on the innate system to one that needs reinforcements as it ages, adapting to needing reinforcements. It cannot be removed,” he said.
The research team genetically analyzed white blood cell samples and analyzed the T-cell response of children and adults at the time of corona infection and a month later. The subjects were 7 children and 5 adult contacts after mild or asymptomatic corona infection. Two additional unrelated adults hospitalized with COVID-19 were included in the study.
The research team found that the children successfully fought off COVID-19 through an immune response in the upper respiratory tract that relies on physical barriers such as mucus and innate immune cells that attack all viruses. “However, after recovery, the children’s memory T-cell response to COVID-19 was poor, indicating that the immune system did not learn how to specifically target the coronavirus,” the research team said. “In essence, a strong innate immune response weakens the adaptive response. do it,” he explained.
Adults, on the other hand, were the exact opposite. Although there were few uncontacted T cells, T cell responses with excellent memory were shown after infection and recovery. “If these results hold, vaccination against COVID-19 in children provides additional support,” the research team said. said.
“These findings may explain why the elderly’s immune system overreacts to COVID-19, causing severe and life-threatening symptoms,” Dr. Pan added. The results of this study (Tracking the clonal dynamics of SARS-CoV-2-specific T cells in children and adults with mild/asymptomatic COVID-19) were published in the journal Clinical Immunology.
