Abstract:
There is increasing interest in the use of adipose-derived mesenchymal stromal cells
(ASCs) for wound repair. As the fate of administered cells is still poorly defined, we
aimed to establish the location, survival, and effect of ASCs when administered either
systemically or locally during wound repair under physiological conditions. To determine
the behavior of ASCs, a rat model with wounds on the dorsal aspect of the hind
paws was used and two treatment modes were assessed: ASCs administered systemically
into the tail vein or locally around the wound. ASCs were transduced to express
both firefly luciferase (Fluc) and green fluorescent protein to enable tracking by bioluminescence
imaging and immunohistological analysis. Systemically administered
ASCs were detected in the lungs 3 hours after injection with a decrease in luminescent
signal at 48 hours and signal disappearance from 72 hours. No ASCs were
detected in the wound. Locally administered ASCs remained strongly detectable for
7 days at the injection site and became distributed within the wound bed as early as
24 hours post injection with a significant increase observed at 72 hours. Systemically
administered ASCs were filtered out in the lungs, whereas ASCs administered locally
remained and survived not only at the injection site but were also detected within
the wound bed. Both treatments led to enhanced wound closure. It appears that systemically
administered ASCs have the potential to enhance wound repair distally
from their site of entrapment in the lungs whereas locally administered ASCs enhanced wound repair as they became redistributed within the wound bed.
