▷Abstract:

Three-dimensional biology — organoids, spheroids, and ex vivo tissue sections — has become a standard experimental unit in cell biology, drug discovery, and regenerative medicine over the past decade. Yet imaging living 3D specimens quantitatively, over long time scales, and across multiple molecular channels remains fundamentally challenging. Point-scanning confocal microscopy provides depth but suffers from phototoxicity and photobleaching; widefield fluorescence lacks optical sectioning in thick specimens; and fluorescence-only approaches are blind to unlabeled but biologically meaningful structures such as extracellular matrix, lipid droplets, lumen, and dead-cell debris.

 

Holotomography (HT) is a label-free imaging modality that reconstructs the three-dimensional refractive index (RI) distribution of a specimen quantitatively, enabling long-term tracking of morphology, dry mass, and subcellular architecture in living cells and organoids without staining. In this seminar, we introduce Tomocube's latest platform, HT-X1 Plus with Spinning Disk Confocal (SDC), which combines (i) a quantitative, label-free HT backbone with (ii) the fast optical sectioning and reduced phototoxicity of spinning disk confocal fluorescence — enabling correlative acquisition of label-free quantitative channels and multi-color fluorescence channels from the same living 3D specimen.

 

The talk is organized in four parts. We first summarize the core imaging bottlenecks of 3D biology. We then introduce the physical principles of holotomography and the quantitative readouts it enables (RI → dry mass, organelle-level segmentation, morphometry). Next, we describe the design of HT–SDC correlative imaging, including how optical, temporal, and sample-coordinate registration are addressed. Finally, we share application data, including (a) label-free tracking of organoid growth and differentiation, (b) multimodal phenotyping of drug response, and (c) live-cell organelle dynamics such as lipid droplet trafficking. We argue that holotomography is not a replacement for fluorescence imaging, but a complementary modality that provides a quantitative baseline layer for 3D biology research.

 

▷Contact: K-BIGHEART (k-bigheart@postech.ac.kr)

------------------------------------------------------------ Demo day------------------------------------------------------------ 

▷Date & Time: June 4, 13:00 ~ 15:00 / 15:00 ~ 17:00

▷Venue: #2003, BOIC

▷Contact: K-BIGHEART (k-bigheart@postech.ac.kr)