A new study has found higher numbers of anti-SARS-CoV-2 antibodies in older males who required hospitalization for COVID-19.
Scientists have found that being hospitalized with COVID-19, as well as being male and of older age, increases the chances of a person having high plasma levels of antibodies that can protect against the disease.
This plasma, which is a component of blood, may help treat the disease in others.
The research, which features in the Journal of Clinical Investigation, is the first step toward confirming whether blood plasma therapy is effective in treating COVID-19.
As scientists continue to search for an effective vaccine for SARS-CoV-2, the virus that causes COVID-19, treatments that can reduce the risk of death are crucial for lowering the mortality rate associated with the disease.
However, to date, research has shown few treatments to be effective.
Furthermore, a major study by the World Health Organization (WHO) — currently available as a preprint — found that remdesivir, the most promising treatment for COVID-19, appears to make no significant difference to the mortality rate.
One possible treatment that may be effective is antibody therapy through convalescent plasma infusion.
Antibody therapies work by infusing a person who has an infection with the plasma of a person who has overcome that infection. The plasma of the person who has recovered may contain antibodies that their body created in response to the initial infection.
Research has suggested that this may be effective in treating people with COVID-19, and observational studies have, so far, produced promising results. However, further research is necessary to confirm these initial findings.
For this research to proceed, however, scientists need a greater knowledge of the makeup of the blood plasma that the process uses so that they can develop a standardized approach to the treatment.
To contribute to this goal, the scientists behind the present article conducted a study to determine what effect age, sex, and the severity of the disease had on the size and overall quality of a person’s antibody response to SARS-CoV-2.
This is important as the antibody response that COVID-19 induces can vary significantly. The scientists behind the present study suggest that this may be because antibodies are typically linked to disease severity, and COVID-19 symptoms can range from undetectable to life threatening.
Determining what factors lead to blood plasma containing antibodies of good quantity and quality may make it easier to standardize and optimize the treatment.
The study involved 126 adults who had recovered from a COVID-19 infection. The researchers took blood from the participants, as well as information regarding their age, sex, and whether they required hospitalization for the disease.
The scientists analyzed the plasma’s ability to neutralize the cells of SARS-CoV-2 in cell cultures. They also used commercially available tests to determine the level of antibodies.
They found that a strong antibody response was associated with hospitalization for the disease, male sex, and older age.
The researchers note that those hospitalized with the disease are likely to have had more severe symptoms and that being older and being male are also associated with a higher risk of severe COVID-19.
As a consequence, they suggest that the severity of the disease may be key to the creation of effective antibodies.
As lead author Prof. Sabra Klein, of the Johns Hopkins Bloomberg School’s Department of Molecular Microbiology and Immunology in Baltimore, MD, notes:
“We propose that sex, age, and severity of disease should be used to guide the selection of donors for convalescent plasma transfer studies because we found that these were significant patient characteristics that not only predicted the amount of antibody but the quality of that antibody.”
– Prof. Sabra Klein
The authors note that their study needs further research to confirm its findings and that other nonblood plasma antibodies, such as the antibodies present in a person’s respiratory tract, may also be crucial to neutralizing the virus.
Nonetheless, they suggest that the study provides a “roadmap” for the identification of people who may be ideal blood plasma donors in the treatment of COVID-19.