COVID-19 triggers depletion of immune system cells: Study
PTI, May 1, 2020, 2:31 PM IST
Beijing: COVID-19 patients have significantly low counts of a cell type that plays a crucial role in immune response, with lower numbers of these cells indicating more severe disease, according to a study whose findings may lead to the development of new therapeutics against the disease.
The study, published in the journal Frontiers in Immunology, assessed COVID-19 patients in China, and found that an adverse immune response triggered in the body may affect disease severity by lowering the counts of T cells, which are a type white blood cells that play important roles in the immune system.
According to the scientists, including those from the Army Medical University in China, COVID-19 patients had a high concentration of cytokines, a protein that normally helps fight off infection.
They said an increased concentration of these molecules can trigger an excessive inflammatory response known as a cytokine storm, which causes the proteins to attack healthy cells.
Coronavirus, the study said, does not attack T cells directly, but rather triggers the cytokine release, which then drives the depletion and exhaustion of T cells.
The findings, according to the researchers, offer clues on how to target treatment for COVID-19.
“We should pay more attention to T cell counts and their function, rather than respiratory function of patients,” said study co-author Yongwen Chen of Third Military Medical University in China, adding that “more urgent, early intervention may be required in patients with low T lymphocyte counts.”
Chen and his team also noticed that many of the patients they treated for COVID-19 had abnormally low numbers of lymphocytes, a type of white blood cell that includes T cells.
“Considering T cells’ central role of response against viral infections, especially in the early stage when antibodies are not boosted yet, we took the T cells as our focal point,” he said.
In the study, the scientists examined 522 patients with coronavirus along with 40 healthy controls.
They said all the patients studied were admitted to two hospitals in Wuhan, China between December 2019 and January 2020, and were between 5 days and 97 years old.
Of the 499 patients who had their lymphocytes recorded, the study noted that 76 per cent had significantly low total T cell counts.
It said ICU patients had significantly lower T cell counts compared with non-ICU cases, and patients over the age of 60 had the lowest number of T cells.
According to Chen and his team, the T cells that did survive were exhausted and could not function at full capacity.
This exhaustion also has implications for COVID-19 patient outcomes, and may leave patients more vulnerable to secondary infection, they added.
The scientists believe future research should focus on finding finer subpopulations of T cells in order to discover their vulnerability and effect in disease, along with identifying drugs that recover T cell numbers and boost function.
They said the existing drug Tocilizumab may be effective, but added that it needs to be investigated in the context of coronavirus.
Udayavani is now on Telegram. Click here to join our channel and stay updated with the latest news.
Top News
Related Articles More
Dogs understand more than they let on, create mental images of known words: Study
ISRO achieves major milestone in RLV Landing Experiment
More risk of malware infection while accessing pirated websites: Study
Piracy sites in India pose greater risk of malware, surpassing adult sites, gambling ads: Study
Online wellness content: 3 ways to tell evidence-based health information from pseudoscience
MUST WATCH
Latest Additions
Height of hypocrisy: Cong hits back at PM over his jibe after lawyers’ letter to CJI
Cong slams Irani for ‘silence’ on women’s issues, asks her to put forward 10-year ‘report card’
One vote can change country’s fate: UP CM Adityanath
Bengaluru: Two arrested for illegally seizing auto over alleged loan default
To browbeat, bully others is vintage Congress culture: PM Modi on lawyers’ letter to CJI