An Image-Based High-Throughput and High-Content Drug Screening Method Based on Microarray and Expansion Microscopy

A high-efficiency drug screening method is urgently neededdueto the expanding number of potential targets and the extremely longtime required to assess them. To date, high throughput and high contenthave not been successfully combined in image-based drug screening,which is the main obstacle to improve the efficiency. Here, we establisha high-throughput and high-content drug screening method by preparinga superhydrophobic microwell array plate (SMAP) and combining it withprotein-retention expansion microscopy (proExM). Primarily, we describeda flexible method to prepare the SMAP based on photolithography. Cellswere cultured in the SMAP and treated with different drugs using amicrocolumn-microwell sandwiching technology. After drug treatment,proExM was applied to realize super-resolution imaging. As a demonstration,a 7 x 7 image array of microtubules was successfully collectedwithin 3 h with 68 nm resolution using this method. Qualitative andquantitative analyses of microtubule and mitochondria morphologicalchanges after drug treatment suggested that more details were revealedafter applying proExM, demonstrating the successful combination ofhigh throughput and high content.

Automated summary

A high-throughput and high-content drug screening method was established by preparing a superhydrophobic microwell array plate (SMAP) and combining it with protein-retention expansion microscopy (proExM). The SMAP was prepared using photolithography, and cells were cultured and treated with different drugs using a microcolumn-microwell sandwiching technology. ProExM was then applied for super-resolution imaging. The successful combination of high throughput and high content was demonstrated by collecting a 7 x 7 image array of microtubules within 3 hours with 68 nm resolution, and revealing more details of microtubule and mitochondria morphological changes after drug treatment.