Vaccines can be redesigned to avoid blood clots, German scientists claim

The coronavirus vaccine developed by AstraZeneca has faced criticism as some people developed ‘blood clots’ after getting jabbed. However, a group of German scientists has found a way to avoid the deadly side effect.

As of now, anyone aged less than 40 faces the risk of developing blood clots after getting the jab developed by AstraZeneca. Considering this, the UK government has been urging people under 40s to opt for the alternatives — such as Pfizer-BioNTech and Moderna — instead of choosing AstraZeneca or Johnson & Johnson.

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The problem lies in 'adenovirus', a common cold virus that is used to deliver the spike protein of COVID-19 into the body, Rolf Marschalek, professor of Goethe university explained.

As per the scientists, the problem arises due to the entry of the adenovirus in the nucleus of the cell, and not just the cellular fluid.

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This leads to splitting of parts of the spike protein, due to which they become mutant protein pieces which can then travel into body parts and lead to blood clotting in some rare cases, the scientists explain.

"The adenovirus life cycle includes the infection of cells … entry of the adenoviral DNA into the nucleus, and subsequently gene transcription by the host transcription machinery," Marschalek explained. "And exactly here lies the problem: the viral piece of DNA…is not optimised to be transcribed inside of the nucleus."

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These vaccines can be redesigned to avoid this problem, in ways similar to Moderna and Pfizer-BioNTech. The scientists claimed that Johnson & Johnson are already in contact with the group to redesign the single-shot vaccine to avoid this side-effect.

"With the data we have in our hands we can tell the companies how to mutate these sequences, coding for the spike protein in a way that prevents unintended splice reactions," Marschalek said.

This study has not been peer-reviewed yet.