Scientists in Germany say they have cracked the cause of the rare blood clots linked to the Oxford / AstraZeneca and Johnson & Johnson vaccines of the coronavirus and believe the blows could be added to stop the reaction from happening at all.
Rolf Marschalek, a professor at Goethe University in Frankfurt who has led research on the rare condition since March, said his research showed that the problem was posed by the adenovirus vectors that both vaccines use to provide protein. spike of the Sars-Cov-2 virus in the body.
The delivery mechanism means that vaccines send the protein spike into the cell nucleus rather than the cytosolic fluid found in the cell where the virus normally produces protein, Marschalek and other scientists have said in a statement. preprint paper published Wednesday.
Once inside the cell nucleus, certain parts of the protein spike splice, or split, creating mutant versions, which are unable to bind to the cell membrane where significant immunization occurs. According to Marschalek’s theory, floating mutant proteins are instead secreted by cells in the body, causing blood clots in about one in 100,000 people.
In contrast, mRNA-based vaccines, such as jabs developed by BioNTech / Pfizer and Modern, provide the genetic material from the spike to the cell fluid and never enter the nucleus.
“When these… Virus genes are in the nucleus they can create some problems,” Marschalek told the Financial Times.
The rare blood clotting reaction that disrupted the development of AstraZeneca and J&J outbreaks was reported in 309 of the 33m people who received the AstraZeneca vaccine in the UK, causing 56 deaths. In Europe, at least 142 people have experienced blood clots from 16m of vaccine recipients.
In response, the use of the AstraZeneca jab has been restricted or suspended in more than a dozen countries. J&J began launching its vaccine in Europe with a warning on its label in April after a brief delay due to concerns.
But Marschalek believes there is a direct “way out” if vaccine developers can modify the sequence of the spike protein to prevent it from spreading.
J&J had already contacted Marschalek’s lab to ask for guidance and was looking for ways to adapt its vaccine to prevent splicing, he said.
The spike protein in the J&J shot was already less prone to “splicing” than the spike protein in the AstraZeneca jab, making the reaction less common, according to Marschalek. In the United States, eight of the 7.4m recipients of the J&J strike reported the rare reaction.
“[J&J] trying to optimize their vaccine now, “he said.” With the data we have on hand, we can tell companies how to mutate these sequences by encoding the protein spike in a way that prevents involuntary splice reactions. “
Marschalek said his lab had not yet discussed its findings with AstraZeneca. “[AstraZeneca] we were never contacted, so we never talked to them, but if they do, I can tell them what to do to make a better vaccine, ”he said.
J&J said: “We support ongoing research and analysis of this rare event as we work with medical experts and global health authorities. We look forward to reviewing and sharing the data when it becomes available.”
AstraZeneca did not immediately respond to the request for comment.
Some scientists have warned that Marschalek’s theory is one of many, and that further evidence is needed to justify his claims.
“There is a lack of evidence to see the causal chain from the splice… Of the protein spike to the events of thrombosis,” said Johannes Oldenburg, professor of transfusion medicine at the University of Bonn. “This is still a hypothesis that needs to be tested by experimental data.”
Marschalek said he had presented the findings of his laboratory to the Paul-Ehrlich Institute of the German government and to the country’s advisory body on vaccination and vaccination.
“They were surprised by our findings because no one thought about the splice problem,” he said.