Published online Sep 26, 2020. doi: 10.4252/wjsc.v12.i9.1013
Peer-review started: June 12, 2020
First decision: July 30, 2020
Revised: August 24, 2020
Accepted: September 1, 2020
Article in press: September 1, 2020
Published online: September 26, 2020
The new coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which emerged in December 2019 in Wuhan, China, has reached worldwide pandemic proportions, causing coronavirus disease 2019 (COVID-19). The clinical manifestations of COVID-19 vary from an asymptomatic disease course to clinical symptoms of acute respiratory distress syndrome and severe pneumonia. The lungs are the primary organ affected by SARS-CoV-2, with a very slow turnover for renewal. SARS-CoV-2 enters the lungs via angiotensin-converting enzyme 2 receptors and induces an immune response with the accumulation of immunocompetent cells, causing a cytokine storm, which leads to target organ injury and subsequent dysfunction. To date, there is no effective antiviral therapy for COVID-19 patients, and therapeutic strategies are based on experience treating previously recognized coronaviruses. In search of new treatment modalities of COVID-19, cell-based therapy with mesenchymal stem cells (MSCs) and/or their secretome, such as soluble bioactive factors and extracellular vesicles, is considered supportive therapy for critically ill patients. Multipotent MSCs are able to differentiate into different types of cells of mesenchymal origin, including alveolar epithelial cells, lung epithelial cells, and vascular endothelial cells, which are severely damaged in the course of COVID-19 disease. Moreover, MSCs secrete a variety of bioactive factors that can be applied for respiratory tract regeneration in COVID-19 patients thanks to their trophic, anti-inflammatory, immunomodulatory, anti-apoptotic, pro-regenerative, and proangiogenic properties.
Core Tip: The new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has reached pandemic proportions, causing coronavirus disease (COVID-19), which leads to severe pneumonia. The lungs are the primary organ affected by SARS-CoV-2, with a very slow turnover for renewal. SARS-CoV-2 enters the lungs and induces immune response with cytokine storm and subsequent organ dysfunction. To date, there is no effective antiviral therapy for COVID-19. Cell-based therapy involving mesenchymal stem cells and/or their secretome is considered a supportive therapy for critically ill COVID-19 patients. Mesenchymal stem cells can regenerate severely injured respiratory tract cells through their trophic, anti-inflammatory, and immunomodulatory properties.