Abstract
"COVID-19" is the word that certainly isn't forgotten by everybody who lives in the first half of the twenty-first century. COVID-19, as a pandemic, has led many researchers from different biomedical fields to find solutions or treatments to manage the pandemic. However, no standard treatment for this disease has been discovered to date. Probably, preventing the severe acute respiratory infection form of COVID-19 as the most dangerous phase of this disease can be helpful for the treatment and reduction of the death rate. In this regard, mesenchymal stem cells (MSCs)-based immunomodulation treatment has been proposed as a suitable therapeutic approach and several clinical trials have begun. Recently, MSCs according to their immunomodulatory and regenerative properties attract attention in clinical trials. After the intravenous transplantation of MSCs, a significant population of cells accumulates in the lung, which they alongside immunomodulatory effect could protect alveolar epithelial cells, reclaim the pulmonary microenvironment, prevent pulmonary fibrosis, and cure lung dysfunction. Given the uncertainties in this area, we reviewed reported clinical trials and hypotheses to provide useful information to researchers and those interested in stem cell therapy. In this study, we considered this new approach to improve patient's immunological responses to COVID-19 using MSCs and discussed the aspects of this proposed treatment. However, currently, there are no approved MSC-based approaches for the prevention and/or treatment of COVID-19 patients but clinical trials ongoing.