Chara Simitzi
UCL, UK
Title: Biodegradable microparticles with hierarchical topographical features influence mesenchymal stem cell behaviour
Biography
Biography: Chara Simitzi
Abstract
Statement of the Problem: Mesenchymal stem cells (MSCs) are becoming increasingly important due to the broad spectrum of trophic and immunomodulatory factors they secrete. The MSC secretome plays a role in angiogenesis and revascularization, immune modulation and tissue repair; however, there is a lack of methods suitable for controlling this effect. Evidence exists to show cell substrates influence MSC behaviour. Therefore, manipulating the cell substrate could provide improved methods for controlling the secretome for new therapies but there is currently a lack of cell substrates suitable for implantation.
Methodology & Theoretical Orientation: The effect of implantable substrates consisting of biodegradable microparticles with hierarchical topographical features was investigated on MSC behaviour and secretome. Poly(DL-lactide-co-glycolide) microparticles were fabricated via the thermally-induced phase separation technique (TIPS). Three different polymer compositions of lactide/glycolide were studied. Microparticles were characterized in terms of surface topography and porosity. Human adipose-derived MSCs (ADMSCs) were attached to the surface of the microparticles
and cultured for 16 days in xeno-free medium. Cell growth on the microparticles was evaluated at different time-points and compared with cells cultured on tissue culture plastic. The angiogenic activity of the ADMSC secretome was evaluated by ELISA and in vitro angiogenesis assays.
Findings: Three different types of TIPS microparticles with different morphological and physicochemical characteristics were investigated. ADMSCs adhered and proliferated on all types of the microparticles. Vascular endothelial growth factor (VEGF) secretion was increased from cells cultured on the microparticles compared with cells cultured on tissue culture plastic. MSCs attached to microparticles remained viable after 16 days, were capable of migrating from the microparticles, and retained their lineage plasticity.
Conclusion & Significance: Our results show that attaching MSCs to biodegradable TIPS microparticles can influence their growth and secretion of pro-angiogenic growth factor. This finding may provide a new method for regenerative medicine