Intervertebral Disc-on-a-Chip^MF: A New Model for Mouse Disc Culture via Integrating Mechanical Loading and Dynamic...

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Tissue Engineering

Background:

• Intervertebral disc degeneration is a major cause of back pain.
• Current ex vivo models lack the microenvironment complexity to accurately study disc health.
• Understanding mechanical loading and nutrition effects is crucial for developing therapies.

Purpose of the Study:

• To develop and validate the Disc-on-a-Chip^MF system for ex vivo intervertebral disc culture.
• To investigate the integrated effects of mechanical loading and nutrition on disc health.
• To establish a platform for studying disc degeneration and testing therapies.

Main Methods:

• Designed a multilayer microfluidic chip with a Computer-Arduino-based control system and mechanical loading unit.
• Optimized axial force measurement using low-profile force sensors (LPFS) and computational simulation.
• Maintained ex vivo mouse disc cultures for 21 days with optimized mechanical loading (0.02 MPa at 1Hz) and flow rate (1 μL/min).

Main Results:

• The Disc-on-a-Chip^MF system maintained disc structural integrity and cell health for 21 days.
• On-chip cultured discs showed preserved collagen, reduced breakdown, and controlled enzyme activity compared to static cultures.
• Disc cell and collagen alignment favored native disc health in the chip model.

Conclusions:

• The Disc-on-a-Chip^MF system accurately mimics the in vivo disc microenvironment.
• This platform is valuable for studying factors influencing disc health and degeneration.
• It offers a promising tool for pre-clinical testing of novel disc therapies.