Assuming also that MSCs are negative for ACE2 and TMPRSS2 SARS-CoV-2 receptor complex (Leng et al., 2020; Moradinasab et al., 2021), MSC transplantation or infusion of MSC derived extracellular vesicles in the context of a deregulated immune response, cytokine storm and lung injury elicited during COVID-19 (especially in older people) appeared as a promising strategy (Gentile and Sterodimas, 2020a,b; Gorman et al., 2020; Monguió-Tortajada et al., 2020; Qin and Zhao, 2020; Rogers et al., 2020; Tsuchiya et al., 2020; Gentile, 2021; Raza et al., 2021). Here, TMPRSS2 is linked to COVID-19.