Immunomodulatory effect of mesenchymal stem cells and mesenchymal stem-cell-derived exosomes for COVID-19 treatment
The world has witnessed unimaginable damage from the coronavirus disease-19 (COVID-19) pandemic. Because the pandemic is growing rapidly, it is important to consider diverse treatment options to effectively treat people worldwide. Since the immune system is at the hub of the infection, it is essential to regulate the dynamic balance in order to prevent the over-exaggerated immune responses that subsequently result in multiorgan damage. The use of stem cells as treatment options has gained tremendous momentum in the past decade. The revolutionary measures in science have brought to the world mesenchymal stem cells (MSCs) and MSC-derived exosomes (MSC-Exo) as therapeutic opportunities for various diseases. The MSCs and MSCExoshave immunomodulatory functions; they can be used as a therapy to strike a balance in the immune cells of patients with coved-19. In this review, we discuss the basics of the cytokine storm in COVID-19, MSCs, and MSC-derived exosomes and the potential and stem-cell-based ongoing clinical trials forCOVID-19. [BMB Reports 2020; 53(8): 400-412]
The world has been facing a dreadful situation due to the spread of the Severe Acute Respiratory Syndrome–Coronavirus-2(SARS-CoV-2) (1). However, neither confirmed effective antiviral medications nor vaccines are available to deal with this emergency(2). Many reports have suggested that it is the cytokine storm in COVID-19 that leads to acute respiratory distress syndrome (ARDS) (3). The cytokine storm in COVID-19 refers to the fact that a variety of cytokines are rapidly produced after viral infections (4). In addition, such a cytokine storm induces hypoxia, and direct viral infection can cause cellular damage. Multiorgan damage and injury have been concomitant withCOVID-19 and can be observed more in patients with a more severe form of the disease (5). Stem cells are specialized cells that can renew themselves by means of cell division and can differentiate into multilineage cells. Mesenchymal stem cells (MSCs) have immunomodulatory features and secrete cytokines and immune receptors that regulate the microenvironment in the host tissue (6). In addition, it has been observed that the crucial role of MSCs in therapy has been mediated by exosomes released by the MSCs. These exosomes have exhibited immunomodulatory, antiviral, anti-fibrotic, and tissue-repair-related functions in vivo; similar effects have been observed in vitro (6).
COVID-19 has invoked frenzy in individuals worldwide. The unceasing increase of infection and death has halted the lives of the citizens of countries everywhere. Hence, it is important to discover novel therapeutic platforms and productive measures without further delay (104). The therapies produced must be easily reproducible and available in large quantities so that enough bioactive molecules will be available for all individuals who have succumbed to COVID-19. MSCs and MSCExoscan be used for their immunomodulatory effects in individuals with COVID-19.