Fig. 1From: Mesenchymal stem cells and their derived small extracellular vesicles for COVID-19 treatmentPossible molecular mechanisms of MSCs against COVID-19. ACE2 and TMPRSS2 are common pathways for SARS-CoV-2 to infect each organ. SARS-CoV-2 enters target cells via its S protein binding ACE2. Meanwhile, SARS-CoV-2 can damage various organs by virtue of specific factors, such as Tau protein in brain, KIM-1, and NLRP3 inflammasome, and MAIT cells. MSCs, mesenchymal stem cells; ACE2, angiotensin converting enzyme 2; TMPRSS2, transmembrane serine proteinase 2; KIM-1, kidney injury molecule-1; MAIT cells, mucosal-associated invariant T cellsBack to article page