Immunomodulatory effect of Mesenchymal stem cells: A blessing to combat cytokine storm appeared during COVID-19 infection

Whilst the manufacture of a safe and potent vaccine for SARS-CoV-2 is the ultimate goal of the COVID-19 response, research is also in progress to develop novel treatments that could facilitate infected patients in the meantime. Casualty in COVID-19 patients are connected with onset of acute respiratory distress syndrome (ARDS) due to its cytokine storm phenomenon resulting in abandoned systemic inflammatory response from the release of pro-inflammatory chemokines (CCL2, CCL3, CCL5, CXCL8, CXCL9, CXCL-10) and cytokines (TNF-α, TGF-β, IFN-α, IFNγ, IL-1β, IL-6, IL-12, IL-8, IL-33). This implies immune system is not capable to turn itself off once it has generated enough of a defense against the virus. An extended cytokine storm will finally shut down breathing completely, which may lead to death. In the context of COVID19, there is a likelihood possibility of treatment of patients by transplanting Mesenchymal Stem Cells (MSCs). MSCs are known to have an immune-regulatory role and MSCs have used in patients that have been affected by the cytokine storm may fine balance the immune system in order to stop the overreaction, without switching it completely off, so that the immune system can carry on to fight the infection. In this review, we have considered the research studies which have used MSCs for the treatment of COVID-19. The cohort study is needed to approve MSCs as therapy, although many clinical trials have been registered to apply MSCs as therapy for severely affected COVID-19 patients.