Application Note: 3D Imaging of Optically Cleared Spheroids in Corning Spheroid Microplates
31 March 2019

The use of three-dimensional (3D) cell cultures for in vitro drug discovery assays has increased dramatically in recent years because 3D cell culture models more accurately mimic the in vivo environment compared to traditional two-dimensional (2D) monolayer cultures. However, current imaging-based analysis of these 3D cultures relies upon techniques originally developed for 2D cell culture, and as such, has significant limitations. Specifically, the light scattering inherent with thick microscopy specimens prevents imaging the entirety of 3D spheroids, which are typically >100 µm in diameter. This technical limitation introduces a sampling bias in imaging analysis in which only the exterior cells of a spheroid can be imaged. To accurately survey the cellular environment and response of the spheroid, the field needs new techniques to overcome the sampling bias.