Mesenchymal Stem Cells for the Treatment of COVID-19: Why and When They Should Be Used?

COVID-19 is a pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which caused deaths of more than 300.000 people around the world within the first few months of 2020. SARS-CoV-2 uses ACE2 receptors to infect respiratory system cells and may cause pneumonia and severe lung damage. The virus can also spread other organs rapidly via ACE2 expressing endothelial cells and cause coagulopathy, and further damage to the organs. Another and probably more harmful effect of the virus is the overreaction of the immune system leading to hyperinflammation causing multiple organ failure and death. Therefore COVID-19 can be considered as a viral infection causing autoimmune disorders. Currently, no vaccine or effective pharmacological treatment established for the disease. On the other hand, Mesenchymal Stem Cells (MSCs) possess anti-inflammatory and immune-regulatory effects along with their regenerative abilities. In this article, we thoroughly evaluate the COVID-19 pandemic and the damage mechanisms on the cellular level which can be ameliorated with the cellular therapies. We also gathered previous and ongoing stem cell clinical trial data from diseases with similar symptoms. All these accumulated data and current clinical trial results indicate that the cellular therapies could be the most effective treatment option for COVID-19 patients to ameliorate the damaged tissues and save lives.