Immunity deviation and failure may be the main cause of severe illness after being infected with SARS-CoV-2

Reporter : Liu Xia / Publisher : Science & Technology Daily 

Translation, editing : Gan Yung Chyan, KUCINTA SETIA

Ref : http://news.sciencenet.cn/htmlnews/2020/8/444230.shtm

 

After being infected with SARS-CoV-2, why do some people get severely ill and some people not? This has always been an unsolved mystery. Now, scientists have written in the latest issue of "Science" magazine that their latest research found that perhaps immune deviation and failure have caused the difference between severe and mild cases of covid.

The researchers explained that this immune bias may stem from the different responses of our innate immune system to SARS-CoV-2. From fruit flies to humans, all organisms have an innate immune system, which can quickly sense viruses and other pathogens. Once it senses viruses, etc., the innate immune system will immediately attack them indiscriminately, and at the same time mobilize "sniper shooter" cells that can perform more precise strikes but are slower, which belong to another branch of the human pathogen defense system ——Adaptive immune system.

Researchers analyzed the immune responses of 76 patients with covid and 69 healthy people. They found that in severely ill patients with new coronary pneumonia, the concentration of molecules that promote inflammation in their blood increased. In addition, they also identified three molecules that are also related to other lung inflammation.

Researchers believe that these three molecules and their receptors may be targets for the treatment of new coronary pneumonia, and they are testing the therapeutic potential of blocking these molecules on animal models of new coronary pneumonia.

According to a recent report by the physicist organization network, scientists also found that the concentration of bacterial fragments (such as bacterial DNA and cell wall materials) in the blood of severely ill patients with covid increased. The more inflammatory substances. Moreover, in severely ill patients with covid, bacterial products usually only found in the intestines, lungs, and larynx may enter the blood, thereby enhancing the inflammatory response and spreading to all parts of the body through the circulatory system.

The study also found that as the disease continues to deteriorate, key cells in the innate immune system of patients with covid have not acted due to the presence of viruses or bacteria, but have been slow to respond.

The senior author of the paper, Dr. Barry Predra of Stanford University School of Medicine, said: "These findings reveal how the immune system can go wrong and cause serious illness during the SARS-CoV-2 infection, and point out potential therapeutic targets."