Abstract
Purpose :
Corneal transplantation is widely considered the most successful treatment for severe corneal trauma. However, only a fraction of patients can benefit from this procedure worldwide due to limited availability of donor corneas. Even then, up to 20% of patients receiving a transplant may experience post-operative complications such as rejection of the donor cornea. The aim of this study was to develop and characterize a novel custom-bioprinted corneal constructs as a potential alternative to donor corneas.
Methods :
Custom-built polydimethylsiloxane (PDMS) rings were developed using Advanced Solutions® BioAssemblyBot® 200 (BAB200) and fitted on 24-well transwell inserts. A gelatin dome made of 6% gelatin solution, was pipetted on the base of the insert. Primary human corneal fibroblasts (HCFs) from healthy subjects were isolated and mixed with a collagen concoction at a volume of 750µL and a density of 15 x 104 HCFs. The HCF/collagen mixture was then pipetted on top of gelatin dome contacting the PDMS rings. Additionally, a collagen concoction without HCFs was pipetted on top of a gelatin dome. Both HCFand acellular bioprinted constructs were placed facing down in the 24-well transwell plates and supplemented with EMEM containing FBS and antibiotics for 1,2, and 4 weeks. The acellular bioprinted constructs were examined using a reflectance confocal microscopy (RCM). The cellularized bioprinted constructs were analyzed using RT-qPCR with the following targets: Collagen 1,3,5 (COL 1,3,5), Smooth Muscle Actin (SMA), and cellular Fibronectin (cFN).
Results :
RCM showed our prototypes with thickness of 0.52mm at the central area and 0.67mm at the periphery, with its dimensions of 7.98mm at its base with a radius of curvature at 4.24mm, mirroring actual human corneal tissue dimensions. Our RT-qPCR data revealed that the bioprinted constructs with the cell density at 150k cells caused a significant upregulation in the expression COL1 in weeks 1 compared to weeks 2 and 4. However, there was no significantly different expression in cFN, COL 5, COL 3, and SMA with the cell density of 150k cells in week 1, 2, and 4.
Conclusions :
Our data suggests that our bioprinted constructs underwent remodeling up to 2 weeks, and at week 4 reached homeostasis. Future studies are warranted in order to optimize the bioprinting construct properties and determine their future clinical impact.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.