Scientists at Moscow State University have found out whether stem cells can become infected with SARS-CoV-2

Employees of the Faculty of Bioengineering and Bioinformatics of Moscow State University and A.N. Belozersky Moscow State University, together with colleagues, analyzed data on the expression of proteins necessary for the penetration of the SARS-CoV-2 coronavirus into the cell, and found that stem cells may be sensitive to viral infection. Scientists suggest that this may be one of the reasons for the high pathogenicity of the new coronavirus. The results of the study can help in understanding the pathological processes in COVID-19 and in finding ways to treat this disease. The work was published in the highly rated journal Scientific Reports.

Widespread circulating human coronaviruses cause mild respiratory diseases with a predominant upper respiratory tract infection in the form of rhinitis or rhinopharyngitis (~ 15% of all cases of acute respiratory diseases). The new coronavirus SARS-CoV-2, a pandemic of which is currently developing, is capable of infiltrating the lower respiratory tract, which leads to severe damage to the lung tissue, often resulting in the death of the patient. To understand how the virus enters the lower respiratory system, and to find ways to treat this condition, it is fundamentally important to identify all types of cells that can become infected with coronavirus. The simplest way to predict which cells a virus can enter is by gene expression analysis,

The first target of the virus is the epithelium, which lines the airways (trachea and bronchi) and the alveoli of the lungs. The epithelium is constantly renewed throughout life due to a few stem cells. The descendants of stem cells are able to transform into different types of cells that perform different functions. In case of damage (for example, in pneumonia), the processes of epithelial restoration require the participation of special populations of stem cells that do not take part in the normal renewal of the epithelium. Damage to stem cells can cause damage to the integrity of the epithelium under normal conditions and its ability to recover from damage.

Researchers from the A.N. Belozersk Moscow State University decided to find out whether different types of epithelial stem cells can be infected with SARS-CoV-2. To do this, they conducted a bioinformatic analysis of data on the expression of proteins necessary for the penetration of SARS-CoV-2 and other coronaviruses into the cell. To enter the cell, the SARS-CoV-2 virus binds to a membrane protein called angiotensin-converting enzyme 2 (ACE2). Proteinases TMPRSS2 and FURIN are also required for the entry of the virus into the cell. The identification of all these proteins is possible using the material accumulated in databases on gene expression in different types of cells. Using these data, it is possible, as a first approximation, to understand which cells and to what extent can be targets of the virus. Knowing the functions of these cells, one can assume the consequences of their infection and death.

Результаты работы свидетельствуют, что стволовые клетки экспрессируют гены, необходимые для проникновения вируса. «Стволовые клетки в ряде случаев могут быть даже более чувствительны к вирусной инфекции, чем окружающие их дифференцированные клетки. Инфицирование стволовых клеток может приводить к нарушениям регенерации эпителия, что, как мы предполагаем, может быть одной из причин высокой патогенности SARS-CoV-2», — рассказала аспирантка факультета биоинженерии и биоинформатики МГУ Анна Валяева, первый автор работы.

Research into the mechanisms of development of pathological processes in COVID-19 using the developed cell models continues in the laboratory of the ultrastructure of the cell nucleus of the Research Institute of Physical Chemistry and Biology, Moscow State University. The emphasis is on studying the effects of viral proteins on lung epithelial cells and the reasons for the high pathogenicity of some coronaviruses. “It is interesting and at the same time important to understand what distinguishes those coronaviruses that cause not mild colds, but serious illnesses. This may also be of practical importance, and not only in relation to the current pandemic, but also to those infections that may appear in the future, ”added Evgeny Sheval, head of the laboratory for ultrastructure of the cell nucleus at Moscow State University .

The research involved the staff of the Institute for Information Transmission Problems named after A.A. Kharkevich RAS and the Gustav Russi Institute (France). Authors from Moscow State University played a key role in the conduct of the work.