Popular science: how the new crown virus "transforms" to escape the immune system "attack"

Source: Medical Network

The battle between humans and the new coronavirus continues. Faced with the pressure of "encirclement and suppression" by the human immune system, the virus is constantly evolving. A new study recently published in the US "Science" magazine shows that the new coronavirus can evade immune system attacks by constantly "transforming".

This study conducted by researchers from the University of Pittsburgh School of Medicine and other institutions found that the new coronavirus can selectively delete tiny fragments of its gene sequence. These deletions occur in the position of the gene sequence responsible for encoding the spike protein, which leads to spikes. The shape of the protein changes, making it difficult for neutralizing antibodies that have never seen the "new appearance" of the spike protein to "catch" it.

The new coronavirus mainly infects human cells through its surface spike protein binding to the "Angiotensin Converting Enzyme 2 (ACE2)" receptor. Therefore, the spike protein has become a key target for the development of new coronavirus vaccines and drugs.

The new study also found that changes in the shape of the spike protein will not make the new coronavirus lose the ability to invade cells and proliferate. Moreover, since the deleted fragments cannot be found by the viral protease responsible for "proofreading" during the viral gene replication process, such mutations will be solidified in the viral genetic information.

Researchers first isolated a virus sample with a missing gene sequence from a patient with immunocompromised new coronavirus, and then analyzed the global new coronavirus sequence database and found that such gene fragment deletions continued to appear in the gene sequence during the virus evolution. The region responsible for encoding the spike protein. For example, the mutation of the new coronavirus discovered in the United Kingdom recently has a gene fragment deleted in this region.

Researchers say the extent to which this "transformation" of the virus will break through the immune system barrier remains to be studied. But if the virus continues to evolve in this way, it may affect the effects of existing vaccines and therapies. Therefore, people need to rely on a variety of ways to fight the virus, such as the development of different antibody combinations and different types of vaccines.