A magnetic resonance-compatible perfusion bioreactor system for three-dimensional human mesenchymal stem cell construct development

Human mesenchymal stem cells (hMSCs) have significant potential for therapeutic tissue regeneration and repair. The creation of functional 3D constructs from hMSCs depends on the innate ability of MSCs to proliferate and differentiate, and is strongly influenced by the culture conditions. An inherent challenge in investigating 3D cellular construct development is the dynamic monitoring of the cellular and physiological environment over the course of construct formation. In this project, a novel 3D MR-compatible perfusion bioreactor using 3D poly(ethylene terephthalate) scaffolds was developed to provide such monitoring. The bioreactor system integrates cell seeding and growth, supports high density 3D tissue construct growth and facilitates repeated nuclear magnetic resonance (MR) signal acquisitions under both static and perfusion conditions. The reactor system also has the capacity to modulate macroscopic flow modes that simulates various tissue growth environments with repeated MR signal acquisition, providing the ability to gain insight into the dynamic interplay between the stem cells in the developing constructs and their microenvironment. Using 1H MR spectroscopy and MR imaging, localized spectroscopic data as well as imaging-based T2 and diffusion quantification were acquired from the hMSC growth construct for up to 40 days.

► We developed a MR-compatible perfusion bioreactor to monitor stem cell construct development.
► The bioreactor integrates construct cultivation and MR monitoring in a single unit.
► The bioreactor can modulate macroscopic flow and allows repeated MR signal acquisitions.
► Parallel and transverse flow were introduced and monitored by MR.