Why some Covid-19 cases become serious while others do not do
A new study found that the Covid-19 virus can reuse immune cells to weaken the body’s defense. This discovery can lead to treatments that promote immunity in severe cases.
In short
- A new study suggests that the covid-19 virus replaces some cells to suppress immunity
- Reprogrammed cells suppress important T cells for virus clearance
- Sars-Cov-2 uniquely triggers immune cell change unlike H1N1 flu
A recent study suggests that the virus behind the Covid-19 has the ability to replace significant immune cells that weaken the body’s ability to fight infection.
During finding out what some people develop serious Covid-19, researchers at the University of Johns Hopkins have found that Sars-Cov-2 virus neutrophils may change the most common type of white blood cells, which weaken the immune response.
Studies published in the US National Institute of Health and Science Translational Medicine suggest that Kovid -19 may lose their ability to fight neutrophil infection in patients.
Instead, these cells begin to suppress other immune cells, especially T cells, which are necessary to clean the virus from the body.
Senior writer of the study, Dr. Andrea Cox said, “In some covid infections, the virus appears to reprogragics in a different type of cell that suppresses T cells. It can help explain why some people develop serious illness.”
These converted cells are known as PMN-MDSCs (polymorphonucleer myeloid-rich cells), seen in cancer and other non-viral diseases, but not usually in viral infections such as Covid-19.
Researchers analyzed blood samples from 39 hospitalized Covid-19 patients and compared them with samples of nine healthy persons. No patient had received covid vaccines like dexamethasone or immunospent drugs.
Among people with severe covid-19, the team found that neutrophil had changed the form, had “humiliated”, released his content and modeled at PMN-MDSC. These reproduced cells expressed two proteins, Lox-1 and PD-L1, which is known to suppress T cell activity.
When researchers exposed healthy neutrophils to the virus in the laboratory, they observed the same change: cells began to suppress T cells, stopping and releasing cytokines, which indicate proteins that activate other immune reactions.
Interestingly, when the same experiment was done using the H1N1 influenza virus, neutrophils did not convert into suppression cells, indicating a unique feature of Sars-Cov-2.
There may be a treatment already a treatment that can compete with this effect. Researchers added PD-L1-blocking antibodies, drugs used in cancer therapy in the neutrophil exposed to Sars-Cov-2. Results: T cells were less suppressed and became more active.
“It suggests that a combination of PD-L1 antibodies with antiviral drugs, or even antiviral is not possible to use them alone, can help patients with severe covids,” Cox said.
CDC defines severe Kovid -19 as a disease resulting in hospitalized, ICU entry or death.
This study provides a deep understanding of how Sars-Cov-2 can kidnap the immune system and cause serious illness and open new doors for treatment that can help the body fight more effectively.
