One of the indelible images of COVID-19 is of ventilators being used to force oxygen into patients’ lungs to try to save them from essentially drowning in their own fluids. A study coauthored by investigators at the Lankenau Institute for Medical Research (LIMR), part of Main Line Health, indicates the SARS-CoV-2 virus’ envelope protein may lead to the accumulation by creating leaks in the lining of the lungs.
According to the study, published Wednesday in PLoS One, the envelope protein may attach to the tails of what are known as tight junctions in the epithelial tissue lining the lungs. The fluid buildup affects patients’ ability to get oxygen, often causing pneumonia, and is a major cause of death in COVID-19.
Given the study results, says LIMR Professor James Mullin, PhD, one of the coauthors of the study, it is critical for clinicians to take preventive measures in patients infected by the coronavirus to prevent respiratory distress where possible and mitigate virus spread. Preliminary evidence indicates zinc and vitamin D are micronutrients that may be able to tighten airway epithelial cell-to-cell junctions.
“Having COVID-infected patients take these micronutrients at levels above recommended daily allowance values may be a common-sense approach,” says Mullin, an expert on the effect of micronutrient consumption and nutrition on reducing epithelial barrier leak. “It could reduce the damaging effects of the virus on the lungs and give the body’s immune system time to ramp up and fight off the virus. That, in turn, could have a significant impact on the mortality rate.”
The most widely known element of the novel SARS-CoV-2 virus is its unique spike protein, which binds to cell receptors. However, there are other major structural proteins. The envelope protein is involved in several aspects of the virus’s life cycle. Among those are the development and severity of disease.
LIMR’s role in the study was contributing its expertise in transepithelial leak in the lining of airway sacs as well as investigating which virus component was causing it. The study was led by the University of Pennsylvania School of Veterinary Medicine, also joined by researchers from the University of Texas, the Wistar Institute of Philadelphia, and the Icahn School of Medicine at Mount Sinai in New York.
Mullin’s research since joining LIMR in 1986 has focused largely on the role of tight junctional leakiness in cancer, aging, infectious diseases and inflammatory diseases in the GI tract, respiratory tract, the oral epithelium and the lining of the uterus. He also is investigating the role of barrier leak in infectious diseases such as Ebola, the hemorrhagic fever virus.