Characterizing the effects of aligned collagen fibers and ascorbic acid derivatives on behavior of rabbit corneal fibroblasts

Abstract

The cornea is responsible for functional optical activity of the mammalian eye, as it must remain transparent in order to focus light onto the retina. Corneal disease is the second leading cause worldwide of vision loss [1]. Human donor tissue transplantation in the cornea is associated with problems such as immunorejection and recurring graft failures [1]. Tissue engineering offers a promising alternative to using human donor tissues in treating corneal diseases. A viable tissue-engineered cornea must be mechanically resilient to protect the fragile intraocular components of the eye, and optically transparent to refract light onto the retina. In the native cornea, transparency is maintained by both the cells in the stromal layer and the high organization of the extracellular matrix (ECM). This study aims to combine the effects of aligned collagen fibers and ascorbic acid derivatives to control corneal fibroblast behavior to not only express the appropriate proteins, but also to deposit aligned, small diameter collagen fibers that resemble the highly organized structure of the natural ECM. Results from this study suggest that the combined effect of an aligned scaffolding material and ascorbic acid supplements can create a cell-matrix construct that both downregulates expression of the light scattering protein a-smooth muscle actin (alpha-sma) and supports an increased number of cell layers.

Surface Topography and Mechanical Strain Promote Keratocyte Phenotype and Extracellular Matrix Formation in a Biomimetic 3D Corneal Model

“…Consistent with previous studies, our pattern‐structured silk films provided a transparent appearance and not only supported cell attachment and proliferation, but also successfully guided the alignment of keratocytes and collagen fibrils in the direction of the grooves, which resembles the highly organized structure of the native cornea. However, in contrast to our results, previous studies have shown that the surface topography of materials may risk altering the gene expression of keratocyte markers and ECM synthesis . The discrepancies to our results in this regard may owe to the different materials used in the previous studies (collagen, polycaprolactone, etc.)…”

Ascorbic Acid Promotes the Stemness of Corneal Epithelial Stem/Progenitor Cells and Accelerates Epithelial Wound Healing in the Cornea

“…Because of that, ascorbic acid has been used to construct cell sheet for tissue engineering application . Ascorbic acid has also been introduced into the culture of corneal cells, mainly on the ECM production of keratocytes . It has been reported that human keratocytes cultured with ascorbic acid for 5 weeks could automatically assemble organized ECM with parallel arrays of fibrils, which are morphologically similar to the corneal stroma .…”

Retinal cell regeneration using tissue engineered polymeric scaffolds

“…Furthermore, they should not trigger any inflammatory, adverse, or immunological responses that might result in scaffold rejection by the body [18]. So far, a large variety of biomaterials has been used to prepare ophthalmic scaffolds, including: natural proteins, such as collagens [4,60] and gelatin [61,62]; natural polysaccharides, such as alginate [63,64] and chitosan [65]; and synthetic polymers, such as poly lactic-co-glycolic acid (PLGA) [66,67] and poly(ε-caprolactone) (PCL) [48,68]. Each of these polymers has its own advantages and disadvantages [18].…”