The last few years have been very exciting for cell biology and drug discovery in general with the application of iPSC-derived models and the introduction of 3D cell culture models which have great promise for better recapitulating complex in vivo functionalities. From a therapeutic discovery perspective, the hope for these models is that they will better predict in vivo outcomes and thus reduce the time and cost to bring a new therapeutic to market. However, one of the challenges with these complex 3D cell culture models is their characterization in that traditional imaging and analysis approaches can be inadequate and even misleading.
Visikol CEO Dr. Michael Johnson recently gave a talk at the National Institute of Health that was focused on how best to characterize 3D cell culture models. The inherent problem of characterizing 3D cell culture models is similar to regular tissues in that they are too thick and opaque to image through and therefore traditional wide-field or even confocal microscopy only tells you what is going on at the surface of these models. Because the surface cells are most exposed to compounds, nutrients, and oxygen, using this imaging data to extrapolate results can be very misleading as it only tells the story of the cells on the exterior and not the entire cell population. This bias has been detailed by Visikol through a recent application note titled 3D High Content Imaging of Optically-Cleared Microtissues for Screening Antiproliferative Cancer Drugs.
While 3D cell culture models could be embedded and sectioned for H&E and IHC, this process is laborious, low throughput and also greatly reduces an experiments sample size as many 3D cell culture models need to be embedded to acquire a single section from a single model. Additionally, based upon the polarity of a 3D cell culture model, this single slice might not be indicative of the phenotype of interest. Therefore, in this presentation Dr. Johnson goes into great detail on how to use tissue clearing to image the entirety of 3D cell culture models in multiple imaging channels without the need to ever section or remove the models from a well plate. Though this type of processing and confocal microscopy can reduce sample throughput compared to traditional wide-field imaging, it greatly increases the amount of data that can be generated per model, improves the accuracy of the conclusions that are made and also allows for the investigation of complex research questions.
“We see our Visikol® HISTO-M™ workflow as an easy-to-use pipeline for acquiring all of the information from 3D cell culture models but do recognize that for every assay there is a delicate balance between data density (i.e. images per model) and throughput,” described Dr. Johnson. Visikol currently sells the Visikol HISTO-M reagent and also offers end-to-end drug discovery services that leverage this technology combined with Visikol’s expertise in 3D cell culture, imaging and image analysis. Specifically, Visikol offers best-in-class 3D cell culture assays using this platform to address questions such as quantifying immune cell infiltration or assessing antibody therapeutic kinetics. If you are interested in discussing a 3D cell culture project or transitioning your 2D cell culture assay into a 3D cell culture assay reach out today.