How SARS-COV-2 Enters The Body

News 2020-181-E EN

Researchers from the U.S. and Europe have found out that the coronavirus SARS-COV-2 enters the body probably mainly via two types of nasal mucosa cells. However, the findings of the present study also indicate that there are other possible ways of infection.

Researchers worldwide are working at full speed on figuring out how the novel coronavirus SARS-COV-2, which causes the lung disease COVID-19, works. It is already known that the virus mainly spreads through droplet transmission and enters the body’s cells through cer-tain proteins. Research teams from the U.S. and Europe, including DZL researchers from the Justus Liebig University Giessen, have identified two cell types which produce a particularly large number of the proteins the virus uses as a gateway into the body. The findings of the scientists have now been published in the medical journal Nature Medicine.

For their studies, the scientists used data from the Human Cell Atlas (HCA), an international large-scale project aiming at mapping all cells of the human body based on their gene ex-pression profiles. Data from the HCA, which is not yet complete, is to help gain a better un-derstanding of human health and create a basis for the targeted diagnosis and therapy of diseases. We know from previous studies that SARS-COV-2 can only infect cells that express two genes required for the virus to enter into human cells (ACE2 and TMPRSS). The current study now shows that ACE2 together with TMPRSS is primarily found in epithelial cells of the respiratory tract, the cornea, and the intestines, which could explain the extensive spreading and diffuse symptoms of the Covid-19 virus. Mucus-producing Becher cells and ciliated cells in the nose showed the highest concentration of these two receptors, so it is very likely that the virus enters the body primarily through the nose. The presence of ACE2 and TMPRSS in other barrier tissue, for example in the superficial epithelial cells of the eye or in the esophagus and colon, show that alternative transmission pathways of the infection need to be further investigated.

These findings could have effects on handling the virus with regard to strategies for the protection against infection and also on the therapy of people infected with COVID-19.

Scientific Contact

Prof. Dr. Christos Samakovlis
Justus Liebig University
Department of Molecular Pneumology
Aulweg 130
35392 Giessen

Further information

Original publication

Waradon Sungnak et al. (2020): „Single-Cell Transcriptomics Data Survey Reveals SARS-CoV-2 Entry Factors Highly Expressed in Nasal Epithelial Cells Together with Innate Immune Genes“. Nature Medicine. DOI: 10.1038/s41591-020-0868-6

The Justus-Liebig-University Giessen (JLU) , founded in 1607, is a research university with a long tradition attracting approximately 28,000 students. In addition to a broad curriculum – from classic natural sciences, law and economics, and social and educational science to lan-guages and cultural sciences – it offers a range of subjects in life sciences which is unique not only in Hesse: human and veterinary medicine, agricultural and environmental sciences, nutrition and food chemistry. Some of the notable personalities who researched and taught at the JLU include a number of Nobel Prize Winners, such as Wilhelm Conrad Roentgen (Nobel Prize for Physics 1901) and Wangari Maathai (Nobel Peace Prize 2004) to name but a few. Since the year 2006, research at the JLU has continuously been funded through the Excellence Initiative and the Excellence Strategy, respectively by the Federal Government and the States (Laender).