A study of transplant recipients undertaken in the early years of the COVID-19 pandemic may have implications for developing and improving future vaccines for immunocompromised individuals.<\/p>\n
As COVID-19 vaccines from Moderna and Pfizer became widely available in 2021, researchers at The University of Toledo asked a fairly straightforward question: Which of the two vaccines would provide the best protection for individuals who had received a kidney transplant?<\/p>\n
In general, their analysis found the Moderna vaccine elicited a slightly higher antibody response in those patients than did the Pfizer version.<\/p>\n
The results, however, were intriguing not because they clearly showed one vaccine was better than the other, but rather because they presented hints about why.<\/p>\n
\u201cThe differences we found between the two vaccines might have been super useful in 2020. At this point, it\u2019s more of a footnote,\u201d said Dr. Michael Rees, a transplant surgeon and professor of urology at UToledo. \u201cWhat makes this research so interesting isn\u2019t comparing vaccine A against vaccine B. It\u2019s what we discovered about vaccines and the immune system\u2019s regulatory response.\u201d<\/p>\n
You can think of the immune system as sort of like the pedals of a car, Rees said.<\/p>\n
There\u2019s a gas pedal that activates the immune response to fight off pathogens and a brake pedal to regulate the immune system to make sure it doesn\u2019t spiral out of control and attack the body itself.<\/p>\n
In the case of the initial round of COVID-19 vaccines, the version developed by Moderna was heavier on the gas. The Pfizer version was stronger on the brake.<\/p>\n
\u201cThe way the Moderna vaccine works seems to rely on a different type of receptor than what the Pfizer vaccine does,\u201d Rees said. \u201cNobody has really identified this idea that the building block of the receptor might move the immune system toward activation or regulation, and our team\u2019s findings suggest that is a very important consideration.\u201d<\/p>\n
In addition to the theory that the lower antibody response produced by the Pfizer vaccine was because of its bent toward regulation, the study also provided new clues about how the immune system regulates itself. The study suggests the immune systems of immunosuppressed patients have a stronger bias toward regulation than they do activation.<\/p>\n