THE DEVELOPMENT OF A NUCLEUS PULPOSUS-ON-CHIP PLATFORM
Prashanth Saseedharan, TP HolsgroveConflict of interest: No conflict of interest
Sources of funding
Funded by UQ- Exeter Institute
Background
Intervertebral disc (IVD) degeneration is strongly associated with low back pain. The nucleus pulposus (NP) is central to disc function, and its degeneration involves loss of proteoglycans, reduced hydration and altered cell metabolism. Current in vitro models – 2D/3D cultures and ex vivo bioreactors – either oversimplify tissue architecture, lack long term nutrient delivery or provide low throughput. Organ-on-chip platforms offer controlled perfusion, mechanical cues and real time monitoring. However, IVD-on-chip or NP-on-chip systems remain limited, with a focus on small animal IVDs or isolated cells. This research aims to address these limitations through the development of an advanced NP-on-chip platform.
Methods
An iterative design strategy was undertaken to optimise the NP chamber, microchannel configuration and sealing interfaces. Modifications addressed optical access, flow obstruction, chamber isolation, tubing integration and structural stability. The device was functionally assessed for perfusion consistency, assembly integrity and explant handling. Preliminary NP explant culture was performed to evaluate the culture viability and optimise protocols for biochemical, histological and molecular analyses.
Results
The fabricated chip achieved stable perfusion across independent chambers with leak-free assembly. The multi-chamber configuration increases throughput and reduces media requirements compared to conventional bioreactor systems. Preliminary explant culture demonstrated viable NP culture
Conclusion
This NP-on-chip device provides a cost-effective, and relatively high throughput system to investigate NP tissue. The current design will be further updated through the integration of mechanical loading. This approach offers a translationally relevant tool to advance mechanistic understanding of IVD mechanobiology in back pain research.