Approaches to drug screening typically involve dramatic compromises in order to achieve high throughput and hold down costs. Examples include the use of immortalized, heterologous cell lines, and genetic engineering to over-express the target protein and/or incorporate a fluorescent surrogate reporter to display the result. At least partly because such systems often produce responses that are not relevant to the actual human disease state, high throughput screening has not historically delivered a strong return on investment. More representative primary cell models are often available for tissues and diseases, but these models are underutilized in screening because of the lack of technological solutions and high costs. For similar reasons, more relevant assay technologies such as endogenous immunocytochemistry and electrophysiology are not commonly employed in HTS. The goal of this project is to bring the gold standard, organotypic cell model for airway epithelia into true high throughput screening, and enable the use of more informative high content assays including endogenous CFTR trafficking and airway surface liquid height. In addition to applications for cystic fibrosis and COPD, the resultant device will also be valuable for skin models and drug transport studies. The device consists of an array of 96 microchambers in standard microplate format. The microchamber design is small enough to be compatible with 384-well plate densities, so 384 microchambers per plate is readily achievable. The plate includes specialized features for compatibility and ease-of-use with standard liquid handling robotics, and high resolution microscopy. Importantly, the device is simple enough to be produced at a cost consistent with the cost constraints of HTS labs, and confers dramatic savings in primary cell and media consumption. The feasibility study on a small-scale device was successfully completed, indicating that the highly miniaturized approach is compatible with organotypic epithelial airway culture at air-liquid interface. Although not an aim of this proposal this device is designed to be integrated into an electrophysiology instrument designed specifically for this culture system.
The project seeks to develop an automatable device that uses the best possible cell models for airways disease, and the best possible tests or assays for the critical functions of human airways. The goal is to help improve the success ratios of bringing a candidate drug to the market for airways diseases like cystic fibrosis and chronic obstructive pulmonary disorder. The device will also be useful for finding drugs for other diseases like skin cancer and certain kidney diseases.
