Mitochondrial Transfer via Tunneling Nanotubes is an Important Mechanism by Which Mesenchymal Stem Cells Enhance Macrophage Phagocytosis in the In Vitro and In Vivo Models of ARDS

Mesenchymal stromal cells (MSC) have been reported to improve bacterial clearance in preclinical models of Acute Respiratory Distress Syndrome (ARDS) and sepsis. The mechanism of this effect is not fully elucidated yet. The primary objective of this study was to investigate the hypothesis that the antimicrobial effect of MSC in vivo depends on their modulation of macrophage phagocytic activity which occurs through mitochondrial transfer. We established that selective depletion of alveolar macrophages (AM) with intranasal (IN) administration of liposomal clodronate resulted in complete abrogation of MSC antimicrobial effect in the in vivo model of Escherichia coli pneumonia. Furthermore, we showed that MSC…

• NI
  National Institutes of Health

  Awards: Grant # P40RR017447, P40RR017447, HL51854
• MR
  Medical Research Council

  Awards: MR/M009149/1, MR/L017229/1, MR/L017229/1
• NH
  National Heart, Lung, and Blood Institute

  Award: HL51854
• NC
  National Center for Research Resources

  Award: P40RR017447