Researchers translate why COVID-19 spares in kids
- Post By : Kumar Jeetendra
- Source: PTI
- Date: 14 Nov,2020
Researchers have found an integral aspect that might explain why the book coronavirus predominantly affects adults and older individuals while seeming to spare younger kids, an advance that may lead to the development of new treatment strategies for COVID-19.
According to the researchers, including those from the Vanderbilt University Medical Center (VUMC) in the united states, children have reduced levels of a receptor protein that the coronavirus SARS-CoV-2 needs to invade airway epithelial cells from the lung.
The findings, published in the Journal of Clinical Investigation, encourage efforts to block this protein to potentially treat or prevent COVID-19 in older individuals, the scientists said.
“Our analysis gives a biologic rationale for why particularly infants and young children appear to be less likely to either get infected or to get severe disease symptoms,” explained Jennifer Sucre, a co-author of this study from VUMC.
They said another cellular protein called TMPRSS2 chops up the spike, so allowing the virus to fuse into the cell membrane and”break into” the cell.
“Our study has always concentrated on comprehension lung growth and how baby lungs differ from mature lungs in their own exposure to injury,” Sucre explained.
“In this study we actually took the opposite approach, and could see how the developing lung by its own differences is shielded from SARS-CoV-2 infection,” she added.
In the study, using a technique known as single-cell RNA-sequencing, the investigators detected the expression of genes in individual mice cells of cells like the lung.
They monitored the expression of genes known to be involved in the body’s response to COVID-19 over time.
While the receptor for ACE2 was expressed at low levels in the mouse ,”TMPRSS2 stood out as having an extremely striking trajectory of increased expression during development,” said Bryce Schuler, yet another co-author of the analysis.
The scientists obtained and analyzed human lung specimens collected from donors of different ages, also confirmed a similar trajectory in TMPRSS2 expression to what they’d found in mice.
“What we discovered is that saying of (TMPRSS2) goes up significantly with aging, and we see at the level of this gene and in the level of this protein. We see a lot more TMPRSS2 in older people, in both humans and mice,” Sucre explained.
Then using fluorescent molecules to analyse autopsy specimens from three patients who died of COVID-19, the researchers discovered the virus in three kinds of cells which express TMPRSS2.
They stated that this receptor protein is well-known for its function in the growth of prostate cancer.
According to the scientists, drugs which block the TMPRSS2 and that have been approved for the treatment of advanced prostate cancer currently are being examined clinically as potential remedies for COVID-19.
“We do believe TMPRSS2 might be an attractive goal both in treatment and possibly as a prophylaxis for people at high risk of COVID exposure,” Sucre added.