Purchase this article with an account.
Andrew Hertsenberg, Michael Burrow, James L Funderburgh; Stromal stem cells prevent corneal scarring after trauma by upregulation of TSG-6 expression.. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):3457.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Corneal scarring leads to vision impairment and blindness in millions of people worldwide. We have recently shown that human corneal stromal stem cells can be obtained in a biopsy-like procedure (termed limbal biopsy-derived corneal stromal stem cells, or LBSC) and used to prevent scarring in a murine model of mechanical wounding. However, the mechanism by which scarring is prevented is yet to be elucidated. We hypothesize that tumor necrosis factor induced protein gene 6 (TSG-6) produced by LBSC is responsible for the prevention of stromal scarring by inhibiting neutrophil infiltration after wounding.
C57Bl/6 mice were anesthetized and the cornea wounded by epithelial and stromal debridement. Immediately after wounding, LBSC embedded in a fibrin gel with or without siRNA to TSG-6 or fibrin gel alone with or without a neutropenia inducing antibody (anti-Ly6G) was applied to the wound bed. Neutrophil infiltration was assed by flow cytometry 24 hours after wounding. One month after wounding, severity of cornel scarring and vascularization was scored by a panel of masked observers. Statistical significance was determined by ANOVA with Tukey post hoc analysis using P<0.05 as significance.
LBSC produced TSG-6 in response TNFα and during differentiation to keratocytes. Treatment with LBSC significantly reduced the number of infiltrating neutrophils 24 hours after wounding, but LBSC with TSG6 knocked down elicited no significant change in neutrophil infiltration compared to untreated wounds. Further, in vivo studies revealed that corneas treated with TSG-6 knockdown LBSC had significantly more scarring than both those treated with LBSC and neutropenic mice.
TSG-6 is produced by LBSC during differentiation in response to TNFα, and when the cells are introduced into corneal wounds. LBSC significantly reduced the number of infiltrating stromal neutrophils compared to LBSC treated with TSG-6 siRNA. Finally, expression TSG-6 by LBSC was required for their ability to prevent corneal scarring.
This PDF is available to Subscribers Only