According to the WHO, more than 61 million people worldwide have been infected with the coronavirus since the beginning of the pandemic, which has so far claimed 1.4 million lives. In most cases of Covid-19 disease, symptoms related to the airways are in the foreground. Concomitant symptoms are now also appearing more and more frequently in other organs of the human body.
A research group consisting of Prof. Dr. Christoph Becker from Erlangen University Hospital and his colleague from Charité – Universitätsmedizin Berlin have now made it their business to examine another human organ affected by corona: the gastrointestinal tract.
Docking point of the coronavirus: the intestine?
The researchers have found that the docking points of the coronavirus are particularly high on the intestinal surface. The Erlanger and Berlin researchers have discovered that certain cells of the intestinal mucosa, so-called enterocytes, have high concentrations of ACE2 and the body’s own enzyme TMPRSS2 in healthy people and can therefore be target cells of the coronavirus. Due to the importance of ACE2 and TMPRSS2 for the penetration of Sars-CoV-2 into the cell, the two molecules represent potential starting points for an effective drug against the coronavirus.
The scientists also found that patients with intestinal inflammation have fewer ACE2 receptors and that both ACE2 and TMPRSS2 change their location in the cells of the intestinal lining. This could mean that the intestines of patients with inflammatory bowel diseases such as Crohn’s disease are more stable to Sars-CoV-2 than the intestines of healthy people. “However, large-scale studies on the importance of the infection of the intestine with the coronavirus are still pending,” says Prof. Becker.
The research also showed that the formation of ACE2 and TMPRSS2 on the cell surface can be influenced from outside. For example, stimulation of the cells via certain microbial signals and messenger substances of the immune system leads to a lower release of ACE2 in the intestinal mucosa. “Our findings show that the molecules on the cell surface that are necessary for infection with Sars-CoV-2 can possibly be influenced therapeutically,” said Dr. Jay Patankar, co-author of the study from Erlangen. Next, the researchers plan to carry out infection experiments on cells to test this thesis.
Future prospects of researchers
The study was made possible by a research network between the Friedrich-Alexander-Universität Erlangen-Nürnberg and the Charité – Universitätsmedizin Berlin. Both locations are Germany’s leaders in the field of intestinal research. In a special research area, scientists from both cities are jointly investigating inflammatory diseases of the intestine. The researchers now want to work together to find out what impact the coronavirus has specifically on the intestine and the functions of the cells there.