In-situ gelling xyloglucan formulations as 3D artificial niche for adipose stem cell spheroids

Three-dimensional spheroidal cell aggregates of adipose stem cells (SASCs) are a distinct upstreampopulation ofstem cells present in adipose tissue, with enhanced regeneration properties in vivo. The preservation of the 3Dstructure of the cells, from extraction to administration, can be a promising strategy to ensure optimal conditionsfor cell viability andmaintenance of stemness potential. With this aim, an artificial nichewas created by incorporatingthe spheroids into an injectable, in-situ gelling solution of partially degalactosylated xyloglucan (dXG) andan ad hoc formulated culture medium for the preservation of stem cell spheroid features. The evolution of themechanical properties and the morphological structure of this artificial niche was investigated by small amplituderheological analysis and scanning electron microscopy, respectively. Comparatively, systems producedwith the same polymer and the typical culture medium (DMEM) used for adipose stem cell (ASC) growth in adherentcell culture conditions were also characterised. Cell viability of both SASCs and ASCs incorporated insidethe hydrogel or seeded on top of the hydrogel were investigated as well as the preservation of SASC stemnessconditions when embedded in the hydrogel.