Vuille-Dit-Bille Emilie, Utz Larissa, Müllner Fiona E, Arteaga-Moreta Valeria J, Hou Yanyan, Spirig Stefan E, Ledroit-Paic Diane, Heub Sarah, Goldowsky Jonas, Weder Gilles, Renner Magdalena
CSEM SA, Neuchâtel, Switzerland.
Institute of Mechanical Engineering, EPFL, Lausanne, Switzerland.
Sci Rep. 2025 Jan 2;15(1):412. doi: 10.1038/s41598-024-83164-2.
Histology is the gold standard for analyzing tissue structure and cell morphology. Immunostaining on thin tissue sections enables precise visualization of antigens and proteins. However, for cryosectioning small tissues such as organoids, spheroids, and tumoroids there is a lack of standardized, time- and cost-effective methods, limiting the throughput of analysis. Here, we have adapted to cryosectioning our previously developed HistoBrick approach, in which small tissue arrangement is spatially controlled within arrayed mini-wells. By testing various embedding matrices, we show that an 8% PEGDA and 2.5% gelatine mixture is optimal, providing essential structural support to maintain sample integrity during cryosectioning. This embedding matrix preserves fragile substructures of human retinal organoids, which are particularly susceptible to damage during sample preparation. Using PEGDA-gelatine HistoBricks for the simultaneous embedding of 16 retinal organoids, we analyzed a time course of retinal organoid development. We observed the maintenance of photoreceptors cell bodies up to week 98 in culture, while photoreceptor outer segments were gradually lost. Further, we observed displaced photoreceptors in the region of outer segments. The PEGDA-gelatine HistoBrick is a cost-efficient tool that can be implemented for small tissue studies to increase throughput in experiments such as large-scale screenings or toxicology research.
组织学是分析组织结构和细胞形态的金标准。在薄组织切片上进行免疫染色能够精确地观察抗原和蛋白质。然而，对于冷冻切片处理类器官、球体和类肿瘤等小组织，缺乏标准化、省时且经济高效的方法，这限制了分析的通量。在此，我们将之前开发的组织砖（HistoBrick）方法应用于冷冻切片，该方法可在排列好的微孔中对小组织排列进行空间控制。通过测试各种包埋基质，我们发现8%聚乙二醇二丙烯酸酯（PEGDA）和2.5%明胶的混合物是最佳选择，它能在冷冻切片过程中提供必要的结构支撑以维持样品完整性。这种包埋基质能保存人类视网膜类器官的脆弱亚结构，这些亚结构在样品制备过程中特别容易受损。使用PEGDA - 明胶组织砖同时包埋16个视网膜类器官，我们分析了视网膜类器官发育的时间进程。我们观察到在培养至98周时光感受器细胞体仍得以维持，而光感受器外节逐渐丢失。此外，我们在外节区域观察到了移位的光感受器。PEGDA - 明胶组织砖是一种经济高效的工具，可用于小组织研究，以提高大规模筛选或毒理学研究等实验的通量。
