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Pfizer and Moderna vaccines are not the same.Studies find differences in antibodies

expansion / / COMIRNATY (Pfizer / BioNTech) vials and Moderna COVID-19 vaccine vials.

The mRNA-based COVID-19 vaccine produced by Pfizer / BioNTech and Moderna has proven to be highly effective in priming the immune system to combat the pandemic coronavirus. However, despite their similar design and efficacy, the two vaccines are not exactly the same-and our immune system does not respond to them as well.

An early hint of this is some real-world tips that found in Phase III clinical trials that there was a surprising difference in the efficacy of the two vaccines, even though both shots worked much the same. It was data.95 percent When 94 percent.. In last year’s delta wave Mayo Clinic Study We found that Pfizer’s effectiveness against infection was reduced to 42%, while Moderna’s effectiveness was reduced to only 76%.

according to New research in scientific translation medicineSuch differences may be explained by evidence that the two vaccines stimulate the immune system to produce slightly different antibodies against SARS-CoV-2.

Both vaccines produce strong levels of neutralizing antibodies that can bind to the virus and prevent cell infection. However, studies have shown that vaccines have produced different antibody profiles overall. Specifically, antibody responses to the Pfizer / BioNTech vaccine were biased towards the class of antibodies commonly found in blood called IgG and IgM. The Moderna vaccine, on the other hand, produced relatively high levels of IgA antibodies. This is a class of antibodies commonly found on mucosal surfaces such as the respiratory tract where SARS-CoV-2 infection begins. In addition, the Moderna vaccine has spurred relatively high levels of antibodies that activate immune cells called natural killer cells.It also activates immune cells called neutrophils to produce high-level antibodies that ingest and kill (phagolate) invading bacteria.

Detailed difference

The study, led by Harvard immunologist and virologist Galit Alter, identified the differences by comparing the antibody profiles of 28 people vaccinated with the Moderna vaccine and 45 people vaccinated with the Pfizer / BioNTech vaccine. The number is small and the participants are primarily healthy young female healthcare workers and do not represent the entire population. This study also did not examine the immune response over time. Instead, researchers looked at antibody profiles about a month after each participant received the second vaccine.

Nonetheless, “despite these limitations, these data provide evidence of potential subtle differences in the quality of the humoral immune response elicited by the SARS-CoV-2 mRNA vaccine,” Alter and her. Colleague writes. Both vaccines produce a strong immune response overall, but these slight antibody differences “may provide insight into the potential differences in protective immunity provided by these vaccines,” they said. Concluded.

Alter and her colleagues need to do further research to determine if these differences are related to differences in defense and vaccine efficacy. We also need to do more research to understand exactly what is making the difference. Pfizer / BioNTech and Moderna vaccines are not only made with different formulations of ingredients, but also given at different doses and at different time intervals between doses. The Moderna vaccine is given in two 100 microgram doses at 4-week intervals, while the Pfizer / BioNTech vaccine is given in two 30 microgram doses at 3-week intervals.

These factors can change how the immune system responds to vaccines. However, digging into these differences may help researchers create “adjustable” mRNA vaccines that produce specific antibody reactions to provide the strongest protection. In the meantime, the findings insist that people use the mRNA vaccine booster in combination, especially if they start taking the Pfizer / BioNTech vaccine. Switching to another vaccine for future boosters may diversify antibody responses and provide broader protection.

https://arstechnica.com/?p=1844672 Pfizer and Moderna vaccines are not the same.Studies find differences in antibodies

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