ABSTRACT
We postulate that similar to bacteria, adult stem cells may also exhibit altruistic defense mechanism to protect their niche. Here, we provide preliminary data on the altruistic stem cell (ASC) based defense against a mouse corona virus; MHV-1 infection. In a mouse model of mesenchymal stem cell (MSC) mediated M. tuberculosis (Mtb) dormancy, MHV-1 infection in the lung exhibited 20 fold lower viral loads than the healthy control mice, suggesting the potential enhancement of an anti-MHV-1 defense by Mtb. This defense involved the in vivo expansion and reprogramming of CD271+ MSCs in the lung to ASC phenotype characterized by activation of genes involved in the HIF-2alpha stemness pathway. The conditioned media of the ASCs exhibited direct anti-viral activity in an in vitro model of MHV-1 induced toxicity to type II alveolar epithelial cells. MHV-1 infected Mtb harboring group versus MHV-1 alone group exhibited an 8-fold (p<0.02; n=4) higher ASC reprogramming and 5-fold (p<0.001; n=3, student t test) higher anti-viral activity. However, ASCs facilitated intracellular replication and extracellular release of Mtb. Thus, our data suggest that MSCs exert an innate defense against MHV-1 by activating the ASC defense mechanism, which might be exploited by dormant Mtb to undergo reactivation. Hence, our findings may provide a novel anti-viral defense mechanism against novel corona virus SARS-Cov2, which could be further utilized to develop vaccine against COVID19. Our findings also predict a potential increase of tuberculosis in post-COVID19 era.
Competing Interest Statement
The authors have declared no competing interest.
