It has been known for about a year that mink can be infected with SARS-CoV-2. The virus had been transmitted from humans to farmed mink and mutated in infected animals. Mutations have been acquired in the spike protein, which is crucial for virus entry into host cells and represents the central point of attack for antibodies. These SARS-CoV-2 variants from mink have been transmitted to humans, raising concerns that mink may be a continuing source of human infection with SARS-CoV-2 variants with altered biological properties .
Researchers at the German Primate Center (DPZ) – Leibniz Institute for Primate Research in Göttingen, Germany have now shown that an antibody used for COVID-19 therapy is unable to effectively inhibit SARS-CoV-2 harboring a advanced mutation acquired in mink. In addition, the mutation reduced inhibition of the virus by antibodies produced in humans infected with SARS-CoV-2. These results show that SARS-CoV-2 can acquire mutations in mink that can reduce the control of the virus by the human immune system (Cell reports).
More than three million people have died worldwide from the pandemic spread of the SARS coronavirus-2 and its associated disease COVID-19, according to the World Health Organization (WHO). Animal-to-human transmission of the virus is believed to be behind the pandemic, which began in Wuhan, China in December 2019. In April 2020, minks on Dutch mink farms developed respiratory disease due to infection with SARS-CoV -2, which was transmitted from infected farm workers to animals. The virus mutated in mink and different variants of the virus appeared, which were transmitted to farm workers and then also transmitted from human to human. This observation was also made in Denmark and millions of mink have been killed to prevent the transmission of new viral variants to humans.
The spike protein in the SARS-CoV-2 envelope is responsible for the virus entering the cells in which it replicates. Researchers led by Markus Hoffmann and Stefan Pöhlmann of the German Primate Center studied mutations detected in the spike protein of mink SARS-CoV-2, including the Y453F mutation. The researchers wanted to know if this mutation affects the inhibition of the virus by antibodies used for COVID-19 treatment or produced in COVID-19 patients.
“Our results show that one of the two antibodies of an antibody cocktail used for COVID-19 therapy no longer effectively inhibits the viral variant with the Y453F mutation. In addition, our study demonstrates that the Y453F mutation reduces the inhibition of the virus by the antibodies produced by COVID -19 patients. This means that people infected with SARS-CoV-2 may have reduced protection against mink variants of the virus, ”says Markus Hoffmann, first author of the study. In sum, SARS-CoV-2 can mutate in mink in a way that reduces immune control by antibodies. It is currently not known whether this is also possible in other animals to which the virus may be transmitted from infected individuals. “In the meantime, the Y453F mutation has also occurred in humans, but not by infection with a variant of mink. When the virus replicates over a long period of time in immunocompromised people, resistant variants may appear. In this case, the virus-mediating resistance mutation was identical to that seen in mink, ”explains Stefan Pöhlmann.
Source of the story:
Material provided by Deutsches Primatenzentrum (DPZ) / German Primate Center. Note: Content can be changed for style and length.