Present Application and Perspectives of Organoid Imaging Technology

Abstract

An organoid is a miniaturized and simplified in vitro model with a similar structure and function to a real organ. In recent years, the use of organoids has increased explosively in the field of growth and development, disease simulation, drug screening, cell therapy, etc. In order to obtain necessary information, such as morphological structure, cell function and dynamic signals, it is necessary and important to directly monitor the culture process of organoids. Among different detection technologies, imaging technology is a simple and convenient choice and can realize direct observation and quantitative research. In this review, the principle, advantages and disadvantages of imaging technologies that have been applied in organoids research are introduced. We also offer an overview of prospective technologies for organoid imaging. This review aims to help biologists find appropriate imaging techniques for different areas of organoid research, and also contribute to the development of organoid imaging systems.

Keywords: imaging technology; microscopy; optical coherence tomography; organoid.

Figure 1

(a) TEM image of airway organoid cross section showing the epithelium structure, and details display apical microvilli and cilia with their characteristic microtubule structure. (b) SEM image of an airway organoid visualizes its 3D architecture, as well as basal and apical ultrastructure. Details display apical surfaces of secretory and multi-ciliated cells. (a,b) are reproduced from [41].

Figure 2

(a) WFFM was used to observe viable and dead cells in the cancer spheroid. Stained with calcein-AM (green) and propidium iodide (PI, red). Reproduced from Reference [81] under the Creative Commons License (CC BY 4.0); (b) FLIM imaging revealed presence of O2 micro-gradients between basal and apical membranes in resting organoids. Reprinted from Biomaterials, 146, D.B.; Okkelman, I.A.; Foley, T.; Papkovsky Dmitriev R.I., Live cell imaging of mouse intestinal organoids reveals heterogeneity in their oxygenation, 86–96,Copyright (2022), with permission from Elsevier; (c) Schematic drawing of SDC microscopy. Reprinted from Methods in Enzymology, 504, Stehbens, S.; Pemble, H.; Murrow, L.; Wittmann, T., Imaging intracellular protein dynamics by spinning disk confocal microscopy, 293–313, Copyright (2022), with permission from Elsevier; (d) Color-coded SDC image of endogenous GFP in a human cerebral organoid. Adapted from [84]. (e) Multiphoton images showing interkinetic nuclear migration of retinal progenitors in the day-20 hESC-derived optic vesicle epithelium. Reprinted from Cell Stem Cell, 10, Nakano, T.; Ando, S.; Takata, N.; Kawada, M.; Muguruma, K.; Sekiguchi, K.; Saito, K.; Yonemura, S.; Eiraku, M.; Sasai, Y., Self-formation of optic cups and storable stratified neural retina from human ESCs, 771–785, Copyright (2022), with permission from Elsevier; (f) Schematic drawing of light sheet 3D reconstruction. Reprinted from Neoplasia, 16, Dobosz, M.; Ntziachristos, V.; Scheuer, W.; Strobel, S. Multispectral fluorescence ultramicroscopy: Three-dimensional visualization and automatic quantification of tumor morphology, drug penetration, and antiangiogenic treatment response, 1–13, Copyright (2022), with permission from Elsevier; (g) Light sheet image of a 6-week-old human cerebral organoid. Reprinted from Cell Stem Cell, 20, Li, Y.; Muffat, J.; Omer, A.; Bosch, I.; Lancaster, M.A.; Sur, M.; Gehrke, L.; Knoblich, J.A.; Jaenisch, R. Induction of Expansion and Folding in Human Cerebral Organoids, 385–396, Copyright (2022), with permission from Elsevier.

Figure 3

(a) STED microscopy showed the distribution of microglia (IBA-1) in relation to the postsynaptic marker PSD95 in cerebral organoids. Reproduced from Reference [92] under the Creative Commons License (CC BY 4.0); (b) STORM was used to visualize hyaluronan (HA) at individual excitatory synapses in 3D cortical spheroid (presynaptic marker vGlut-1, blue; HA, red; postsynaptic marker PSD95, green). Reproduced from Reference [140] under the Creative Commons License (CC BY 4.0); (c) Confocal (i) and (iii) and SIM (ii) and (iv) images for the NapBu-BPEA-stained (Zn2+ fluorescent probe) HeLa cells. Reproduced from Reference [141] under the Creative Commons License (CC BY 4.0).

Figure 4

(a) In vivo development of retinal organoid transplant monitored by OCT. Reproduced from Reference [171] under the Creative Commons License (CC BY 4.0); (b,c) D-FFOCT 3D image (b) differentiation process is shown in the top row and the cell’s dynamic active region is shown in the bottom row (c) of hiPSC-derived retinal organoids. Reproduced from Reference [173] under the Creative Commons License (CC BY 4.0).