To date, corneal epithelial reconstruction has been very successful. However, in a number of cases of injury or disease, the stromal layer is affected. Our goal is to develop biomaterials that will enable the regeneration of the corneal stroma. In this study, we compare endogenous vs exogenous stem cell courses for corneal stromal regeneration.
We have previously developed collagen-based corneal stromal extracellular matrix substitutes based on EDC crosslinked collagen, and have shown that they promote ingrowth of stromal cells from the host cornea (Merrett et al. 2009; Fagerholm et al. 2010). For cases where stromal progenitors are depleted, we developed a non-toxic collagen-based hydrogel system where a macromolecular photoinitiator (Dex-BBA)was used to form the hydrogel around cells. The feasibility of Dex-BBA as a photoinitiator to initiate the gelation of aminoethylmethacylate-modified collagen (Coll-AEMA) was examined with or without the presence of stroma cells.
The Dex-BBA crosslinked hydrogels were weaker than the EDC crosslinked constructs. However, they were fairly robust and no apparent toxicity of the hydrogel system to mesenchymal stroma (or stem) cells (MSCs)were observed during the culture of 7 days, which indicated that Dex-BBA based macrophotoinitiator and our collagen-based hydrogel system may have potential in corneal stromal regeneration applications.
We show that corneal stromal regeneration can be achieved by endogenous stimulation of existing corneal progenitor cells. Where the host cells may be depleted, our results show that hydrogel encapsulated stem cells may be used in the future.
European Association for Vision and Eye Research (EVER-2011), October 5–8, Crete, Greece