Department of Biological Sciences, Center for Cancer, Genetic Diseases, and Gene Regulation, Fordham University, Bronx, NY 10458, USA.
Department of Biological Sciences, Center for Cancer, Genetic Diseases, and Gene Regulation, Fordham University, Bronx, NY 10458, USA.
Exp Eye Res. 2014 Sep;126:51-60. doi: 10.1016/j.exer.2014.01.010. Epub 2014 Apr 26.
RPE cells are the most actively phagocytic cells in the human body. In the eye, RPE cells face rod and cone photoreceptor outer segments at all times but contribute to shedding and clearance phagocytosis of distal outer segment tips only once a day. Analysis of RPE phagocytosis in situ has succeeded in identifying key players of the RPE phagocytic mechanism. Phagocytic processes comprise three distinct phases, recognition/binding, internalization, and digestion, each of which is regulated separately by phagocytes. Studies of phagocytosis by RPE cells in culture allow specifically analyzing and manipulating these distinct phases to identify their molecular mechanisms. Here, we compare similarities and differences of primary, immortalized, and stem cell-derived RPE cells in culture to RPE cells in situ with respect to phagocytic function. We discuss in particular potential pitfalls of RPE cell culture phagocytosis assays. Finally, we point out considerations for phagocytosis assay development for future studies.
RPE 细胞是人体中最具吞噬活性的细胞。在眼睛中，RPE 细胞始终与杆状和锥状光感受器的外节接触，但仅每天一次有助于脱落和清除远端外节尖端的吞噬作用。对 RPE 吞噬作用的原位分析已经成功地确定了 RPE 吞噬机制的关键参与者。吞噬过程包括三个不同的阶段，识别/结合、内化和消化，每个阶段都由吞噬细胞分别调节。在培养的 RPE 细胞中对吞噬作用的研究允许专门分析和操纵这些不同的阶段，以确定其分子机制。在这里，我们比较了原代、永生化和干细胞衍生的 RPE 细胞与原位 RPE 细胞在吞噬功能方面的相似性和差异。我们特别讨论了 RPE 细胞培养吞噬作用测定的潜在陷阱。最后，我们指出了未来研究中吞噬作用测定发展的注意事项。
