The Main Mechanisms of Mesenchymal Stem Cell-Based Treatments against COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has a clinical manifestation of hypoxic respiratory failure and acute respiratory distress syndrome. However, COVID-19 still lacks of effective clinical treatments so far. As a promising potential treatment against COVID-19, stem cell therapy raised recently and had attracted much attention. Here we review the mechanisms of mesenchymal stem cell-based treatments against COVID-19, and provide potential cues for the effective control of COVID-19 in the future. METHODS: Literature is obtained from databases PubMed and Web of Science. Key words were chosen for COVID- 19, acute respiratory syndrome coronavirus 2, mesenchymal stem cells, stem cell therapy, and therapeutic mechanism. Then we summarize and critically analyze the relevant articles retrieved. RESULTS: Mesenchymal stem cell therapy is a potential effective treatment against COVID-19. Its therapeutic efficacy is mainly reflected in reducing severe pulmonary inflammation, reducing lung injury, improving pulmonary function, protecting and repairing lung tissue of the patients. Possible therapeutic mechanisms might include immunoregulation, anti-inflammatory effect, tissue regeneration, anti-apoptosis effect, antiviral, and antibacterial effect, MSC - EVs, and so on. CONCLUSION: Mesenchymal stem cells can effectively treat COVID-19 through immunoregulation, anti-inflammatory, tissue regeneration, anti-apoptosis, anti-virus and antibacterial, MSC - EVs, and other ways. Systematically elucidating the mechanisms of mesenchymal stem cell-based treatments for COVID-19 will provide novel insights into the follow-up research and development of new therapeutic strategies in next step.

The Intersection of COVID-19 and Rheumatoid Arthritis: Shared Mechanisms, Treatment Challenges, and Potential Therapeutic Approaches.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading rapidly across the world, posing a major health concern with the coronavirus disease 2019 (COVID-19). Patients with rheumatoid arthritis (RA) may be at higher risk of infection and disease progression due to impaired autoimmune systems, immunosuppressants, and comorbidities. Therefore, we review the possible immune mechanisms and pathological interactions between COVID-19 and RA, as the uncontrolled immune activation and cytokine response in COVID-19 resemble the immune inflammation of RA. We also discuss the potential mechanisms that may lead to cardiovascular complications as well as the challenges of treating RA patients with COVID-19. While several therapeutic agents are being developed to cure COVID-19, antirheumatic drugs could also be potential options due to the similar proinflammatory cytokines induced in both diseases. Additionally, we discuss the safety and effectiveness of SARS-CoV-2 vaccines and novel therapeutic approaches against RA based on the shared mechanisms between COVID-19 and RA.