Kevin Dean: "Imaging the Metastatic Cascade with Axially Swept Light-Sheet Microscopy."

Kevin Dean (UT Southwestern Medical Center)

Abstract: In melanoma, metastasizing cells are distributed broadly throughout the host via the general circulatory system. Yet, in a process known as organotropism, the colonization and formation of metastases at a particular site in a distant tissue is non-random and occurs in a patient-specific format. Why this is true remains poorly understood but is likely to involve a combination of cell intrinsic (e.g., the ability of a cell to survive differences in mitogenic factors, nutrient availability, and/or context-specific stressors) and extrinsic factors (tissue-specific mechanical and biochemical cues). Gaining molecular insight into the events involved in metastatic colonization is challenging, in part because such events are rare, pioneer colonies are small, and potential sites of colonization are widely distributed throughout large tissues (~10 x 7.5 x 4 mm). To identify the earliest events in metastasis, including the colonization of a tissue by a single metastatic cell, we are developing a self-driving Multiscale Cleared Tissue Axially Swept Light-Sheet Microscope (MCT-ASLM). MCT-ASLM consists of two imaging systems arranged in a 4-axis geometry that together enables rapid imaging of large (~20 x 20 x 20mm) cleared tissues with 5-micron resolution, automatic identification of biological features of interest, and subsequent interrogation of these events with an isotropic resolution of ~330 nm. Microscope operation is performed with custom, performant, and highly reconfigurable Python software that permits the creation of acquisition “recipes” according to the specimen and biological feature of interest. Beyond metastasis, such an approach greatly accelerates the evaluation of sub-cellular features in select cells within the greater context of whole, intact tissues.