Beyond The Chip: Microphysiological Systems On Multi-well Plates

Abstract

The drug development process is lengthy and expensive, with a 90% failure rate among drugs entering clinical trials due to the inadequacy of predictive models in the initial phases of drug development. To overcome these limitations, there is a paradigm shift towards developing micro physiological systems often referred as Organ-on-a-Chip that have be shown to recapitulate organ level functions in vitro. However, despite their promise, these systems often have limited throughput, restricting their widespread use in the drug development process. The work outlined in this thesis aims to bridge this gap by integrating the physiological relevance offered by micro physiological systems with the high throughput capabilities of traditional 2D multi-well plate cultures.

The thesis outlines the development of two novel micro physiological systems, engineered in a high throughput multi-well format called the IFlowPlate and AngioPlate. Both the platforms have an open-top design and unlike tradition microphysiological platforms does not need complex pump systems and have built-in connections to achieve perfusion making it more scalable and user-friendly. The IFlowPlate leverages the self-assembly capability of endothelial cells to create a perfusable vascular network. This platform technology was utilized in this work to achieve intravascular perfusion of colon organoids for the first time and demonstrated immune cell circulation and recruitment in response to injury.

AngioPlate, the other platform that was developed as a part of this work, utilizes a pre-patterned scaffold completely embedded in native hydrogel matrix to guide cells in forming organ-specific geometries and tubular structures using a novel subtractive manufacturing technique. This platform allowed for fabricating complex and intricate networks to model vascularized terminal lung alveoli and renal proximal tubules. This work demonstrated for the first time that highly complex perfusable tissues embedded in hydrogel can be integrated with multi-well plates to mimic tissue specific structures and interfaces without the use of synthetic membranes or plastic channels. The built-in perfusion channel and the flexible hydrogel matrix allowed for the terminal lung alveoli model to be mechanically actuated to mimic breathing motions. The renal proximal tubule model was used to mimic glucose reabsorption in kidney and model renal inflammation.

The latter part of this work focusses on further improving this platform to increase platform robustness and to allow for incorporating supporting cells such as fibroblasts into the hydrogel matrix. This allowed us to model tubular injuries in kidney such as cisplatin induced -nephrotoxicity and TGF- β1 induced- tubulointerstitial fibrosis. Furthermore this work also describes the development of a high-throughput TEER meter that can be integrated with the AngioPlate platform allowing for rapid, non-invasive measurement of renal epithelial barrier integrity.

Given that both platforms are designed in a 384-well plate format, they are high throughput and compatible with existing technologies like high-content imaging systems, robotic liquid handling systems, and microplate readers allowing for widespread adoption across diverse research settings. It is anticipated that the contributions described in this work will significantly advance our understanding of disease propagation and accelerate drug development process.