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Introduction: This study was conducted to compare the effect of nanofibrous polycaprolactone (PCL) and PCL/gelatin (PCL/Gel) on limbal epithelial stem cell (LESC) and its efficiency for transplantation in animal model. Methods: PCL and PCL/Gel with a mass ratio of 70:30 and 50:50 was fabricated by electrospinning method. Human LESCs were cultured on PCL and PCL/Gel scaffolds and the effect of each scaffold on LESC proliferation, attachment and corneal epithelial regeneration in an animal model was evaluated, considering ease of use of scaffold and final transparency of the cornea. Results: Our data showed that PCL was more suitable than PCL/Gel for LESCs adherence, induction of epithelial morphology and proliferation. Histopathologic analysis of corneal sections from transplanted animals showed that epithelium was regenerated almost similar in PCL and PCL/Gel groups; however, vascularization and inflammation were significantly lower in the group receiving PCL. Conclusion: The represented data indicated the priority of PCL to PCL/Gel for the LESC attachment, proliferation and final outcome in an animal model of alkaline injury. This finding might be promising for cell therapy of corneal diseases.
RESUMEN
PURPOSE: Retinal pigment epithelial (RPE) cells are capable of differentiating into retinal neurons when induced by the appropriate growth factors. Amniotic fluid contains a variety of growth factors that are crucial for the development of a fetus. In this study, the effects of human amniotic fluid (HAF) on primary RPE cell cultures were evaluated. METHODS: RPE cells were isolated from the globes of postnatal human cadavers. The isolated cells were plated and grown in DMEM/F12 with 10% fetal bovine serum. To confirm the RPE identity of the cultured cells, they were immunocytochemically examined for the presence of the RPE cell-specific marker RPE65. RPE cultures obtained from passages 2-7 were treated with HAF and examined morphologically for 1 month. To determine whether retinal neurons or progenitors developed in the treated cultures, specific markers for bipolar (protein kinase C isomer α, PKCα), amacrine (cellular retinoic acid-binding protein I, CRABPI), and neural progenitor (NESTIN) cells were sought, and the amount of mRNA was quantified using real-time PCR. RESULTS: Treating RPE cells with HAF led to a significant decrease in the number of RPE65-positive cells, while PKCα- and CRABPI-positive cells were detected in the cultures. Compared with the fetal bovine serum-treated cultures, the levels of mRNAs quantitatively increased by 2-, 20- and 22-fold for NESTIN, PKCα, and CRABPI, respectively. The RPE cultures treated with HAF established spheres containing both pigmented and nonpigmented cells, which expressed neural progenitor markers such as NESTIN. CONCLUSIONS: This study showed that HAF can induce RPE cells to transdifferentiate into retinal neurons and progenitor cells, and that it provides a potential source for cell-based therapies to treat retinal diseases.
