Stem cell therapy for COVID-19 and ARDS The major life-threatening symptoms of COVID-19 disease are the result of the dysregulation of the immune system, wherein the cascading release of cytokines, termed a cytokine storm, induces severe inflammation. In past studies, stem cells have demonstrated immune-modulating properties, with the capacity to suppress T-cells, prevent the maturation of dendritic cells, lessen B-cell activation and proliferation, and inhibit the proliferation and cytotoxicity of natural killer cells. Stem cell therapy has also been employed against viruses such as HIV, hepatitis B, and virus-associated acute respiratory distress syndrome (ARDS), a leading mortality factor in those with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.