Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, 44892 Bochum, Germany.
Centre for Ophthalmology, University Eye Hospital Tübingen, 72076 Tübingen, Germany.
Biomolecules. 2022 Jul 16;12(7):990. doi: 10.3390/biom12070990.
The pathological events of age-related macular degeneration are characterized by degenerative processes involving the photoreceptor cells, retinal pigment epithelium (RPE), and the Bruch's membrane as well as choroidal alterations. To mimic in vivo interactions between photoreceptor cells and RPE cells ex vivo, complex models are required. Hence, the aim of this study was to establish a porcine organotypic co-cultivation model and enlighten the interactions of photoreceptor and RPE cells, with a special emphasis on potential neuroprotective effects. Porcine neuroretina explants were cultured with primary porcine RPE cells (ppRPE) or medium derived from these cells (=conditioned medium). Neuroretina explants cultured alone served as controls. After eight days, RT-qPCR and immunohistology were performed to analyze photoreceptors, synapses, macroglia, microglia, complement factors, and pro-inflammatory cytokines (e.g., , , ) in the neuroretina samples. The presence of ppRPE cells preserved photoreceptors, whereas synaptical density was unaltered. Interestingly, on an immunohistological as well as on an mRNA level, microglia and complement factors were comparable in all groups. Increased levels were noted in ppRPE and conditioned medium samples, while was only upregulated in the ppRPE group. was elevated in conditioned medium samples. In conclusion, a co-cultivation of ppRPE cells and neuroretina seem to have beneficial effects on the neuroretina, preserving photoreceptors and maintaining synaptic vesicles in vitro. This organotypic co-cultivation model can be used to investigate the complex interactions between the retina and RPE cells, gain further insight into neurodegenerative pathomechanisms occurring in retinal diseases, and evaluate potential therapeutics.
年龄相关性黄斑变性的病理事件的特征是涉及光感受器细胞、视网膜色素上皮 (RPE) 和 Bruch 膜以及脉络膜改变的退行性过程。为了模拟光感受器细胞和 RPE 细胞在体内的相互作用，需要复杂的模型。因此，本研究的目的是建立猪器官型共培养模型，并阐明光感受器和 RPE 细胞之间的相互作用，特别强调潜在的神经保护作用。猪神经视网膜外植体与原代猪 RPE 细胞 (ppRPE) 或源自这些细胞的培养基（=条件培养基）共培养。单独培养的神经视网膜外植体作为对照。八天后，进行 RT-qPCR 和免疫组织化学分析，以分析神经视网膜样本中的光感受器、突触、大胶质细胞、小胶质细胞、补体因子和促炎细胞因子（例如， ， ， ）。ppRPE 细胞的存在保存了光感受器，而突触密度没有改变。有趣的是，在免疫组织化学和 mRNA 水平上，所有组的小胶质细胞和补体因子都相似。ppRPE 和条件培养基样本中 水平升高，而仅在 ppRPE 组中上调。条件培养基样本中 水平升高。总之，ppRPE 细胞和神经视网膜的共培养似乎对神经视网膜有益，保存光感受器并维持体外突触小泡。这种器官型共培养模型可用于研究视网膜和 RPE 细胞之间的复杂相互作用，深入了解发生在视网膜疾病中的神经退行性病理机制，并评估潜在的治疗方法。
