Abstract
Purpose: :
Mesenchymal stem cells (MSCs) can be isolated from several tissues including the cornea. Our goal was to establish in vitro assay for studying human corneal stroma injuries and the role stroma-derived stem cells have on immunity, wound healing and neovascularization processes.
Methods: :
Human corneal buttons were harvested from cadavers (tissue collection complied with the guidelines of the Helsinki Declaration and was approved by the Regional Ethical Committee). Following removal of the epithelial and endothelial layers, stromal cells were proliferated in vitro on cell culture plate in medium containing human serum as the only supplement. To confirm MSC-like phenotype, FACS and gene array analysis, immunofluorescent staining and standardized in vitro differentiation assays were used. Functional tests including mixed lymphocyte response, wound healing and vascular tube-formation were also performed.
Results: :
Corneal stroma cells could grow in culture for more than 10 passages (n=6). The most important markers of MSCs (CD73, CD90, CD105, CD 44, CD147, PDGFRb) were highly expressed, and no endothelial or hematopoietic cell markers were present on their surface. Differentiation into adipogenic, chondrogenic and osteogenic lineages were successful. Corneal stroma MSC-like cells could suppress the proliferation of activated peripheral blood lymphocytes, migrated and closed wounds within 24 hrs in vitro and formed vascular tube-like structures spontaneously within 8 hrs on Matrigel.
Conclusions: :
We demonstrate an animal material free technique for cultivating MSC-like cells obtained from human corneal stroma. Their role in immunity, wound healing and angiogenesis could be studied in vitro, possibly serving as a model for examining corneal stroma injuries and their treatment accordingly.
Keywords: cornea: stroma and keratocytes • wound healing