Washington:
People infected with the original strain of the virus that causes COVID-19 early in the pandemic made antibodies that never bind properly to newer variants, according to a study.
The discovering, published in the journal Nature Communications, has implications for the capacity of new variants to reinfect persons who contracted earlier versions of the virus, as properly as for the continuing efficacy of vaccines and the design and style of booster shots.
The researchers mined published papers about COVID-19 patients for information about the sequence of the antibodies they made. They focused on antibodies against the spike protein, the aspect of the virus that binds to receptors on human cells to infect them.
The spike protein is the target of most vaccines.
The group discovered that quite a few antibody sequences converged into two most important groups, indicating a constant human immune response to the virus.
“We really focused on characterising the antibodies created in those infected with the original strain of the virus,” mentioned study very first author Timothy Tan, a graduate student at the University of Illinois Urbana-Champaign, US.
“Before we started the study, variants weren’t much of a problem. As they emerged, we wanted to see whether the common antibodies we identified were able to bind to newer variants,” Tan mentioned.
The researchers studied the convergent antibodies’ capacity to bind to quite a few variants and discovered that they no longer bound to some.
When persons make rather related antibodies to a unique virus, it is known as convergent antibody response.
“Even though this antibody response is very common with the original strain, it doesn’t really interact with variants,” mentioned study leader Nicholas Wu, a professor at the University of Illinois.
This raises the concern of the virus evolving to escape the body’s most important antibody response, the researchers mentioned.
Some antibodies need to nonetheless be helpful — the body tends to make antibodies to quite a few components of the virus, not only the spike protein — but the unique groups of antibodies seen in the study will not be as helpful, they mentioned.
The researchers mentioned they would like to conduct related research characterising antibody response for Delta and other variants, to see no matter if they also create a convergent response and how it differs from the original strain.
“We want to design vaccines and boosters, if needed, that can protect a majority of the population,” Tan mentioned.
“We expect that the antibody response to those variants would be quite different,” he added.
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