Visualization of 3D Organoids Through the Latest Advancements in Microscopy

Organoids have enhanced our understanding of in vivo biological processes and the scaling from cells to tissues to organs. Modern advancements in organoids have achieved recapitulation of the complex processes in tissue morphogenesis, including genetic regulation of differentiation, cell migration, rearrangements, as well as large-scale morphological features. As these processes span different scales in space and time, there has also been a growing need for improvements in microscopy techniques that can capture relevant biological processes and their interaction with the local environment. Imaging three-dimensional tissues and organoids requires a careful understanding of the optical properties of the system and specialized sample preparation. Importantly, these properties have to be fine-tuned based on applications. Ongoing advancements in imaging technologies, particularly light-sheet microscopy, which excels in photo-gentleness and temporal resolution, have enabled researchers to study organ development in toto and have provided valuable insights into mechanisms and regulation of pathways linked to development and disease, among others. In this chapter, we review the current state-of-the-art microscopy techniques and sample preparation methods available for capturing biological processes in organoids across scales.