Single-objective multiphoton light-sheet microscopy for tumor organoid screening

To study cancer progression and drug response, researchers have developed methods to derive tumor organoids from primary tissues, which not only have the same proteomic and genetic abnormalities as the malignant disease but also better replicate tumor behaviors than 2-dimensional culture models. It has been shown that tumor organoids can be used to predict treatment response, understand drug resistance, and study tumor heterogeneity at the individual-patient level. Whereas large-scale production of patient-derived organoids in standard flat-bottom 1,536-well plates has recently been demonstrated for cytotoxicity screening of 3,300 approved drugs, no suitable functional imaging tool can provide rapid 3-dimensional (3D) evaluation over a wide range of cellular states in these mass-produced organoids. The traditional two-photon scanning microscopy is too slow, while the conventional light-sheet microscopy is not compatible with microwell plates. Here we propose a microplate-compatible single-objective multiphoton light-sheet microscopy (SOMP- LSM) that can provide high imaging speed for 3D imaging analysis of organoids and deeper imaging depth with sub-cellular resolution. Our simulation of 3D point-spread function simulation for the SO-MP-LSM shows that our imaging system can achieve 270 nm lateral resolution and 800 nm axial resolution deep into organoids.