Dr Catherine Le Visage and her group at the Regenerative Medicine and Skeleton (INSERM U119) based in the School of Dental Surgery, University of Nantes – France has derived an ingenious way to treat discogenic low back pain, something several of us experience as we age. A common reason of low back pain is the degeneration of the intervertebral disc (IVD), which is a fibrocartilaginous tissue located between each vertebrae in our spine. Current treatment does not address the etiological cause of disc degenerative disease (DDD) thus regenerative medicine approaches are considered with deep interest – in particular, the stimulation of local cells by in situ injection of growth factors targeting IVD degenerative process.
Dr Le Visage’s approach is an injectable biphasic system of pullulan microbeads (PMBs) dispersed within a cellulose-based hydrogel (Si-HPMC). Pullulan is a neutral, linear and non-immunogenic polysaccharide that is widely used because of its natural properties (biodegradable, biocompatible, non-toxic). The research team demonstrated a sustained release of growth factors TGF-β1and GDF-5 in vitro for up to 28 days, while maintaining biological activity on human cells. In addition, they were able to measure for the first time the mechanical properties of the PMBs through a parallel plate compression test with the CellScale MicroTester.
Images above –
Top left: Pullulan microbeads observed with a confocal microscopy
Bottom left: Pullulan microbeads observed with a scanning electron microscope
Right: Pullulan microbeads mechanical characterization. A hydrated single PMB was compressed between 2 plates using a MicroTester. Force and displacement data were recorded and a representative curve was presented.
This study is part of a larger comprehensive and continuous study to improve treatment options of DDD through regenerative medicine. You can read more about Dr Le Visage’s work here: https://rmes.univ-nantes.fr/