Fig. 1 Schematic of SARS-CoV-2 infecting lung epithelial cells, and priming approaches to improve MSCs therapeutic efficacy for the treatment of COVID19 patients. (a) Represent a few priming approaches (priming by inflammatory cytokines and LPS, hypoxia pre-conditioning, (b) Primed MSCs, (c) SARS-CoV-2 and ‘Primed MSCs’ post-infusion in the lung, (d) Therapeutic effect exerted by MSCs (immunosuppression, reparative, angiogenesis, homing, anti-apoptotic, and anti-microbial activities)