A new study has revealed that the high amount of antibodies in the body of patients who survived the Corona virus infection may mistakenly attack healthy organs and tissues. According to the research, this may also apply to those who have mildly recovered from the Covid-19 disease.
The research conducted on 177 healthcare workers who were infected with the Corona virus and recovered before the vaccines came out, found that all of these people had resistant autoantibodies, and some of these autoantibodies caused chronic inflammation; revealed that it causes damage to the joint, skin and nervous system. “We wouldn’t normally expect such a wide range of autoantibodies to remain at such high levels in people who recover within six months of full clinical recovery,” said Susan Cheng of Cedars-Sinai Smidt Heart Institute in Los Angeles.
“We don’t yet know how long the antibodies will remain in the body at high levels beyond six months, or whether they will cause any significant clinical symptoms. It will be important to keep people under follow-up,” Cheng said.
Cheng and his team are investigating whether elevated autoantibody levels are linked to persistent symptoms in people with long Covid survivors. The team also plans to investigate the levels of autoantibodies in people infected with the new variants of the Corona virus.
Omicron weakens B-cells, but cannot succumb
Researchers think that the effect of antibodies developed by the “memory B cells” of the immune system against the Omicron variant of the Corona virus is weakened, but this effect is still important.
After the human body learns to recognize the Corona virus through infection or vaccination, B cells develop fresh antibodies if there is not enough antibodies in the blood to neutralize the virus. In a study published ahead of independent science board review in bioRxiv, a repository that provides free access to studies in biology, experts analyzed the potency of more than 300 antibodies produced by memory B cells from vaccinated volunteers. Among these volunteers, there are also those who have previously had Corona infection.
“Omicron appeared to have succeeded in eliminating most of the memory B-cell pool,” said two experts at the University of Paris, Matthieu Mahevas and Pascal Chappert, and that Omicron “was absorbed by 30 percent of all antibodies and close to 10 percent of virus-inactivating antibodies.” effectively recognized”. Experts speculate that the ability of memory B cells to proliferate and form antibodies “in less than two days” may compensate for the reduced effectiveness of antibodies.
Experts say the effect of B cells, along with other components of the immune system, especially T cells, explains why most people who are vaccinated but infected do not suffer from severe illness requiring hospitalization.
The activity of virus variants in cells makes these variants more effective.
According to experts, mutations in the spike protein that allows the Corona virus to enter the cell, as well as other mutations that change the behavior of the virus after it enters the cell, help explain why some variants are more contagious.
Nevan Krogan of the University of California at San Francisco of the findings, published in the journal Nature, said experts “should start looking at mutations outside of the spike protein as well.” The spike protein, which forms the protrusions on the outer surface of the Corona virus, is the main focus of vaccine and antibody drugs. Krogan’s team investigating the Alpha variant revealed that a mutation outside of the spike protein causes virus-infected cells to increase production of a protein called Orf9B. Orf9B disables TOM70, a protein that sends signals to cells’ immune system. Elevated levels of Orf9B prevent the immune system from responding adequately to the infection, causing the virus to overpower the immune system.
Referring to the elevated level of the Orf9B protein, Krogan said, “It is rare for mutations to ‘make out’ a protein. This is a very insidious behavior exhibited by the virus.” Stating that the same mutation also occurred in the Delta variant, the expert said that almost the same mutation is also present in Omicron, which may mean that virus variants have similar effects in the immune system. Recent findings may lead to the development of drugs that can target the interaction between Orf9B and TOM70 proteins.