The study has been published in Science, and the researchers studied the new variants first identified in the UK (B.1.1.7), in South Africa (B.135.1), in India (B.1.617), and in Brazil (P.1).
Coronavirus variants: Coronavirus variants that spread fast contain mutations which are able to help the virus escape from the immune response that is generated in the human body naturally or through vaccines, which is why such variants are a cause of concern. However, to get more insight into how this issue can be tackled, it is also important to understand how these mutations actually work, that too urgently. Now, key details to understand how these escape mutations function have been found in a new study conducted by scientists at Scripps Research along with Germany and the Netherlands-based collaborators.
The study has been published in Science, and the researchers studied the new variants first identified in the UK (B.1.1.7), in South Africa (B.135.1), in India (B.1.617), and in Brazil (P.1). They looked at how important neutralising antibodies bind themselves with the original strain of SARS-CoV-2 in high resolution using structural biology techniques. They also used these techniques to study how mutations in these new variants disrupted that binding process.
Scripps Research, in a statement, said that the scientists found several of the mutations clustered in a site called the receptor binding site, and this site is located on the virus’ spike protein, while other sites remain unaffected.
Researchers looked at three mutations in the spike protein of the virus, viz N501Y, K417N, and E484K. The study said that these mutations were found in most of the major variants of the coronavirus, either alone or in combination. Moreover, all of them were found in the receptor binding site or the place where the virus attaches to the host cells in humans.
Upon testing major classes of antibodies targeting the area in and around these sites, researchers discovered that in the presence of the mutations, the antibodies are unable to bind and neutralise the virus. They then used structural imaging techniques and mapped these portions of the SARS-CoV-2 at an atomic-scale resolution, and looked at how the sites where the antibodies would otherwise be able to bind and neutralise are being affected by these mutations.
The study also stated that the antibodies are capable of neutralizing the original strain found in Wuhan, but the variants are able to escape this immune response, indicating a need for updated vaccines at a later stage.
However, the scientists also said that these mutations did not affect any other vulnerable sites on the virus, and they specifically also demonstrated that the antibodies that targeted two areas outside the receptor binding site were not impacted by these mutations.
As per this study, future vaccines and treatments based on antibodies might be able to provide a higher level of protection against coronavirus and its variants if they are used against areas that lie outside the receptor binding site in the virus.