Researchers at the Center for Genetics & Society at the University of Washington took a close look at a coronavirus — the same one that appears to have infected four Americans with the potentially deadly virus in the summer of 2012 — and found that it attacks a patient’s fat tissue more than any other part of the body.
The team, headed by Andrew Wetzler, a professor of microbiology and immunology, found that the bulk of the virus — about 40 percent — attacks the molecular fat cells of humans and rats, essentially nibbling on the fibers that organize these cells in the body. Fat cells are structures that help keep our bodies in shape, but are also vulnerable to outside chemicals, like toxins.
Interestingly, the fat cells of mice targeted by the virus did not show evidence of the virus. This suggests that the host’s immune system protects these cells from the infection.
This study is part of a larger effort to understand the commonalities among coronaviruses and their response to factors like pain and fever.
Previous work by Wetzler and his colleagues has shown that most or all of the dangerous viruses in the human and animal hosts, including the flu, are primarily produced in the respiratory system. In a viral infection, the source of the virus is typically left unknown. However, scientists already knew from a study published in 2012 in the journal Science that these viruses are usually created by passing viruses along from infected bats to other animals.
Other research has been done to see how people are infected by these viruses. A 2009 study, for example, revealed that roughly one in a thousand people getting sick in Nigeria were sickened by the coronavirus known as SARS, or SARS-like virus. The study was published in the New England Journal of Medicine. The researchers suggested that when the virus is found to be present in the food people eat, the virus’ likelihood for becoming airborne increases. In this 2009 study, similar to the 2011 study, the virus infected the eyes of mice in poultry.
In the current study, researchers were particularly interested in this link to food consumption because they want to understand the transmission of the virus in the modern day.
The World Health Organization has warned that the disease is spreading among travelers to Saudi Arabia, Jordan, Qatar, Egypt, and the United Arab Emirates, and last month, the WHO said that 38% of cases appeared to be caused by new cases of the coronavirus.
As in the 2013 study, Wetzler did not try to genetically isolate the virus from the humans to see if it was the same one as in those four patients. He and his team did however see that many of the human cases were infected when someone with the virus traveled to a place with a confirmed or probable source of the infection.
These recent findings present a more comprehensive look at the process by which human cells are infected by the coronavirus and could help doctors and health officials determine how these viruses can potentially spread in the host.
But the research also comes with its own challenges. With so many people around the world infected with the coronavirus and the virus spread globally, the scientists wanted to study the virus in a stable environment that was not highly populated. They tried to use different strains of rats that are prone to the coronavirus rather than caged rodents, as is the case in most of the populations of both rats and humans. Additionally, there are still large geographic gaps between infected populations, so not being able to study some people and some places could present challenges.
“If we were able to study more humans in certain locations, we might be able to see that other places have a different disease that’s closer to home,” said Wetzler. “So that would be important.”
These limitations did not diminish the researchers’ excitement in trying to gain answers to one of the most perplexing diseases affecting humanity.
“We’re very excited by this work,” said Wetzler. “We’re currently testing this in mouse models and hope to publish soon on this work.”