Abstract
Purpose:
An estimated 10 million people suffer worldwide from vision loss caused by corneal damage. For the worst cases, the only available treatment is transplantation with human donor corneal tissue. However, in numerous countries there is a considerable shortage of corneal tissue of good quality, leading to various efforts to develop tissue substitutes.The present study aims to introduce nanofibrous scaffold of poly (glycerol sebacate) PGS as a biodegradable implant, for the corneal tissue engineering.
Methods:
Nanofibrous scaffolds were produced by electrospinning method and different compositions of PGS and poly(ε-caprolactone)(PCL).The biocompatibility of the material was tested in vitro by MTT assay on days 1,3,5, and 7 to test cell viability of human corneal endothelium cells(HCEC). Cells treated with medium only were served as a negative control group. Density of the grown cells was studied by determining the absorbance intensity.To examine a potential immunological reaction of the scaffolds, samples were exposed to mononuclear cells derived from peripheral blood(PBMCs). As positive controls for induction of proinflammatory mediators, PBMCs activated by CD3 and IL2 in contact and without contact to scaffolds were used. After an incubation period of 3 days, supernatants were assayed for apoptotic assessment and immunogenic potentials by Annexin FITC V and FACS analysis.
Results:
We could successfully demonstrate that cultivation of HCECs on PGS/PCL scaffolds was possible. Compared to day 3, cell density determined by microplate absorbance was significantly higher after 7 days of cultivation(p<0.0001). According to the MTT data, none of the samples showed toxicity. However, cell proliferation rates differed amongst samples. Apoptotic assessments by FACS analysis showed that no composition stimulated apoptosis or activated PBMCs. All the compositions were inert for the T-cells. After 3 days the highest viability percentages comparable with negative control are belonged to un-stimulated PBMCs and PBMCs stimulated by IL2 in contact to the scaffolds.
Conclusions:
PGS/PCL scaffolds produced with different component compositions are well suitable for cultivation of conjunctival and corneal endothelial cells. The scaffolds do not promote premature cell death and do not trigger certain immune reactions tested in vitro. Further studies are under way to gain more insight into cell-scaffold interaction.
Keywords: 607 nanotechnology •
426 apoptosis/cell death •
481 cornea: endothelium