Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA.
Institute for Vision Research, Department of Ophthalmology and Visual Science, University of Iowa, Iowa City, IA, USA.
Stem Cells Transl Med. 2024 Jun 14;13(6):582-592. doi: 10.1093/stcltm/szae022.
Retinal degenerative diseases are a major cause of blindness involving the dysfunction of photoreceptors, retinal pigmented epithelium (RPE), or both. A promising treatment approach involves replacing these cells via surgical transplantation, and previous work has shown that cell delivery scaffolds are vital to ensure sufficient cell survival. Thus, identifying scaffold properties that are conducive to cell viability and maturation (such as suitable material and mechanical properties) is critical to ensuring a successful treatment approach. In this study, we investigated the effect of scaffold stiffness on human RPE attachment, survival, and differentiation, comparing immortalized (ARPE-19) and stem cell-derived RPE (iRPE) cells. Polydimethylsiloxane was used as a model polymer substrate, and varying stiffness (12 to 800 kPa) was achieved by modulating the cross-link-to-base ratio. Post-attachment changes in gene and protein expression were assessed using qPCR and immunocytochemistry. We found that while ARPE-19 and iRPE exhibited significant differences in morphology and expression of RPE markers, substrate stiffness did not have a substantial impact on cell growth or maturation for either cell type. These results highlight the differences in expression between immortalized and iPSC-derived RPE cells, and also suggest that stiffnesses in this range (12-800 kPa) may not result in significant differences in RPE growth and maturation, an important consideration in scaffold design.
视网膜退行性疾病是导致失明的主要原因之一，涉及光感受器、视网膜色素上皮（RPE）或两者的功能障碍。一种有前途的治疗方法是通过手术移植来替代这些细胞，以前的工作表明细胞输送支架对于确保足够的细胞存活至关重要。因此，确定有利于细胞活力和成熟的支架特性（如合适的材料和机械特性）对于确保成功的治疗方法至关重要。在这项研究中，我们研究了支架刚度对人 RPE 附着、存活和分化的影响，比较了永生化（ARPE-19）和干细胞衍生的 RPE（iRPE）细胞。聚二甲基硅氧烷被用作模型聚合物底物，通过调节交联剂与基底的比例来实现不同的刚度（12 至 800 kPa）。使用 qPCR 和免疫细胞化学评估附着后基因和蛋白质表达的变化。我们发现，尽管 ARPE-19 和 iRPE 在形态和 RPE 标志物表达上存在显著差异，但基质刚度对两种细胞类型的细胞生长或成熟都没有实质性影响。这些结果突出了永生化和 iPSC 衍生的 RPE 细胞之间表达的差异，也表明在这个范围内（12-800 kPa）的刚度可能不会导致 RPE 生长和成熟的显著差异，这是支架设计中的一个重要考虑因素。
