A study has found that the Moderna and Pfizer-BioNtech coronavirus vaccines produce a continuing immune response, indicating that they offer long-lasting protection against Covid. The study, published in the peer-reviewed journal Nature on Monday, found that the vaccines “induce persistent” production of antibodies, “enabling the generation of robust humoral immunity.”
These vaccines also produced a high level of antibodies against three known variants of the coronavirus. There was an even stronger antibody response to the variants among those vaccinated after already being infected with Covid. The researcher only studied those who received the Pfizer-BioNtech vaccine and produced inoculation as the Moderna shots; it uses the same mRNA technology. Many existing vaccines use bacterial proteins or bits of the virus to prompt an immune response. The mRNA-based coronavirus vaccines make the body make and release spike proteins, which then increase the immune response.
According to a report Monday from the Washington University School of Medicine, whose scientists led the research, “The immune response to such vaccines is both strong and potentially long-lasting.” Though other studies have found the levels of antibodies in the blood of vaccinated people over time, the new research took a closer look at how the immune response developed in the body. Researchers found out that in the lymph nodes, germinal centers of participants in the study after receiving their first vaccine shot were still very active for four months.
According to senior author Ali Ellebedy, associate professor of pathology and immunology, of medicine, and molecular microbiology, “Germinal centers are the key to a persistent, protective immune response. Germinal centers are where our immune memories are formed. And the longer we have a germinal center, the stronger and more durable our immunity will be because there’s a fierce selection process happening there, and only the best immune cells survive.”
For the study, forty-one people were examined, eight of whom had previously been infected with Covid, and all were given the standard two doses of the Pfizer-BioNTech vaccine. From 14 of the people, germinal samples were taken who received the vaccine, three weeks after their 1st dose and just before getting their 2nd. At weeks 4, 5, and 7 additional samples were taken. Samples from 10 participants were taken 15 weeks after they 1st tarted the vaccine doses. None of those who gave germinal samples had previously caught Covid.
The researcher found out that after three weeks, germinal centers located in the armpits were formed in all 14 participants. Eight of ten participants at the end of the study period tested still had detectable germinal centers containing B cells targeting the virus. After the 1st vaccine shot was given 15 weeks after that, the germinal centers were still producing immune cells.
The study examined blood samples from all 41 people who received the Pfizer vaccine. After the 1st dose of vaccine, the antibody levels were seen to rise slowly in those not affected by Covid but rose much more rapidly in those infected with Covid.