Yale study: SARS-CoV-2 can directly invade the brain, increasing fatality rate

Reporter : Xiao Jing / Editor : Yun Tao / Publisher : New Tang Dynasty Television

Ref : https://www.ntdtv.com/gb/2020/09/11/a102938617.html

Translation, editing : Gan Yung Chyan, KUCINTA SETIA

Image : A research team at Yale University in the United States recently discovered that some patients infected with SARS-CoV-2 suffer from headaches, mental disturbances and confusion. The reason may be that the virus directly invades the brain. (Creative Commons / Wikimedia)

The Yale University research team recently discovered that some patients infected with SARS-CoV-2 (covi, in short; CCP virus, novel coronavirus) have headaches, mental disorders, and mental disorders, which may be caused by direct virus invasion. The virus invades the brain or accelerates death.

The team led by Akiko Iwasaki, a professor of immunology at Yale University, followed three methods to conduct research: one is to infect brain organoids grown in the laboratory with the CCP virus; the other is to infect mice with covi and the third is to test for covi in the brain tissue of a dead patient.

The results showed that they found that covi in the brain organoids can infect neurons, and then control the mechanism of neuronal cells to replicate themselves, and the infected cells accelerate the death of surrounding cells by stifling the supply of oxygen.

However, as of now, doctors have always believed that the nervous system of about half of patients with covi may be affected by the abnormal immune response that causes inflammation of the brain, that is, the "cytokine storm", rather than the virus directly invading the brain. One of the main arguments of this theory is that the level of the ACE2 protein in the brain is not high enough, and covi is attached to this protein. There are a lot of ACE2 in lungs and other organs.

But Iwasaki's research team found that the brain organoids had enough ACE2 protein to help covi invade the brain, and this protein was also found in the brain tissue of the deceased. They also performed a lumbar puncture on a patient who was mentally disordered during hospitalization and found that the spinal fluid of this person contained antiviral neutralizing antibodies, which was more beneficial to their theory.

Later, the research team studied two groups of laboratory mice. One group was genetically modified to have only ACE2 receptors in the lungs, and the other group only had ACE2 receptors in the brain.

The results showed that a group of mice whose lungs were infected with covi showed some signs of lung damage. However, the group with brain infections suffered a sudden weight loss and died quickly. This shows that when covi invades the brain, it is likely to increase the fatality rate.

Finally, the research team examined the brains of three patients who had died from complications of covid and found evidence that they contained covi to varying degrees. The researchers also found that the infected brain area showed no signs of infiltration by immune cells such as T cells. This may prove that the "cytokine storm" of an overactive immune response may not be the main cause of neurological symptoms.

The research team speculated that covi may enter the brain through the nose. However, they also emphasized that the above conclusions need to be verified by more studies and more autopsy is needed to understand the prevalence of brain infections in patients.

The Iwasaki team’s research is still in its preliminary stages, but it provides new evidence that SARS-CoV-2 can replicate itself in the brain, causing nearby brain cells to hypoxia, but its prevalence is unknown. The team said that this conclusion is not too surprising, because SARS virus can also break through the "vascular-brain barrier" to block foreign substances, and Zika virus can also do this, causing serious brain damage to the fetus.