Sputnik V produces a better neutralizing antibody response to Omicron than the mRNA vaccines, Professor Hildegund Ertl; one of the top US vaccine specialists, said, according to a statement posted on the Sputnik V Twitter page on Monday.
The vaccine and immunotherapy researcher from the Wistar Institute in Philadelphia believes the Russian shot’s adenoviral vector provides for a “far longer” expression of antigen than any of the mRNA vaccines.
This results in “stimulation of durable antibody-secreting cells,” the statement said.
“Overall, these results are extremely promising,” Professor Ertl said; while commenting on the results of a comparative study presented by a joint Russian-Italian team working at the Spallanzani Institute, Italy’s leading research institute for infectious diseases. The team published a preprint of the study last week.
The researchers studied the serum samples from individuals vaccinated with Sputnik V and Pfizer and found that; the Russian shot produces a level of virus neutralizing antibodies against Omicron twice as high as the US vaccine; which means better protection against the virus.
“Among all samples, 74.2% of Sputnik V-vaccinated sera were able to neutralize Omicron vs 56.9% for Pfizer-vaccinated;” the RDIF said in a statement, citing the study’s results.
It was also said that the Russian shot demonstrates a significantly smaller reduction of virus neutralizing activity against Omicron in comparison to the original Covid-19 strain.
Sputnik V shows a roughly eightfold reduction in its effectiveness against the new strain; while the Pfizer-BioNTech vaccine is 21 times less effective.
Professor Ertl is one of the leading researchers behind the development of vaccines for a wide range of diseases, including Covid-19, AIDS, chronic viral infection, and even some forms of cancer.
She believes that the disparities in the virus neutralizing response demonstrated by the two vaccines might “reflect differences in the antigen structure and duration of its expression.”
She also pointed to the fact that Sputnik V produced high antibody titers against the original “wild” Covid-19 strain, which remains stable for six months after vaccination; while the protection level induced by the mRNA vaccines declined by 10 times over the same period.
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The Italian study’s results were welcomed by Ancha Baranova; a molecular biology specialist at George Mason University’s Institute for Biohealth Innovation.
According to Baranova, Sputnik V provides a wider pool of antibodies to the spike protein;\ than the vaccines used in the US.
The molecular biologist explained that American vaccine developers artificially changed the configuration of the Covid-19 spike protein for their vaccines; thus making them capable of producing antibodies narrowly tailored to it.
These changes made the vaccines less effective at detecting and neutralizing Omicron; which has a highly mutated spike protein and is capable of evading the immune response to a certain extent.
Sputnik V’s researchers did not introduce any specific changes into the Covid-19 protein used in their vaccine.
This provided for a more diverse antibody response, Baranova said, adding that the immune system of those vaccinated with Sputnik V produces “more various antibody types,” thus increasing the chance of successful virus neutralization.
Alexander Gintsburg, the head of the Gamaleya National Center for Epidemiology and Microbiology, praised the results of the joint study; which researchers from his center conducted with the Italian specialists.
He said the results confirm the data obtained by his team in a separate study published in late 2021; adding that “hard scientific data proves Sputnik V has higher virus neutralizing activity against Omicron as compared to other vaccines.”