Elucidation of the mechanism of how the new coronavirus escapes from the human immune system

A research group led by Professor Koichi Kobayashi of the Graduate School of Medicine, Hokkaido University has elucidated the mechanism of how the new coronavirus (SARS-CoV-2) escapes from the human immune system and sustains infection.

SARS-CoV-2 inhibits induction of the MHC class I pathway by targeting the STAT1-IRF1-NLRC5 axis | Nature Communications


What's New: Succeeded in elucidating the immune escape mechanism of the new coronavirus-expected to contribute to understanding the pathophysiology and new treatment methods- (Professor Koichi Kobayashi, Graduate School of Medicine)

COVID-19 Breakthrough: Scientists Discover How the SARS-CoV-2 Virus Evades Our Immune System

The human immune system is made up of multiple defense systems that protect you from viral infections. Of this defense system, the 'immune cells needed to eliminate the virus from the body' are cytotoxic T cells. Cytotoxic T cells detect viral antigens, locate and destroy cells infected with the virus, and prevent the virus from multiplying.

In order for immune cells to be able to find viral antigens, a molecule called MHC class I is required, but Professor Kobayashi and his research team have found that the MHC class required for infection protection in the lung and throat cells of SARS-CoV-2 infected individuals. Discover that the amount of I is low. Further investigation revealed that SARS-CoV-2 also suppressed the amount and function of the immune system's NLRC5 protein, which is required to increase the amount of MHC class I.

In other words, SARS-CoV-2 causes impaired expression of MHC class I by reducing both the amount and function of NLRC5, and escapes from the immune response by cytotoxic T cells.

Furthermore, the research group has succeeded in elucidating which gene of SARS-CoV-2 has an immune system inhibitory effect and its mechanism. This makes it possible to explain the mechanism by which SARS-CoV-2 escapes from the immune system, hides in the human body for a certain period of time, proliferates, and then infects others. Professor Kobayashi said, 'The reason why SARS-CoV-2 propagates in the human body very easily is because a specific gene of the virus has a suppressor gene called ORF6 that acts to inhibit the function of NLRC5, so MHC class I Because it also hinders it. '

Since the research group has found that a specific gene for SARS-CoV-2 has an immunosuppressive effect, it is expected that a new therapeutic method targeting this gene will be developed. 'This new discovery will enable us to develop a new drug that can block a specific gene for SARS-CoV-2, and the immune system will be SARS,' said Paul de Figueiredo, an associate professor at the University of Texas A & M School of Medicine, who worked with Professor Kobayashi. -I hope I can fight CoV-2 forever. '

in Science, Posted by logu_ii