3D cultures of rat astrocytes and brain capillary endothelial cells on Poly-L-lactic acid scaffolds

Tissue engineering is an emerging multidisciplinary field that aims at reproducing in vitro and/or in vivo tissues with morphological and functional features similar to the biological tissue of the human body. In this communication we report setting of three-dimensional structures able to mimic the extracellular matrix of the nervous system: we prepared Poly-L-Lactic Acid (PLLA) porous scaffolds via thermally induced phase separation (TIPS), and investigated the parameters that influence porosity, average pore size and degree of interconnection, i.e. polymer concentration, temperature and time of process. Astrocytes and brain capillary endothelial cells (BCECs) were cultured on these three-dimensional structures and tested for their ability to grow and survive on PLLA scaffolds. We analyzed in parallel the cell growth in 2D and 3D culture systems and observed the differences in cell morphology by fluorescence analysis: three-dimensional scaffolds have the ability to guide cell growth, provide support, encourage cell adhesion and proliferation. Astrocytes and BCECs adapted well to these porous matrices, not only remaining on the surface, but also penetrating inside the scaffolds. This 3D cell culture system could be further enriched to host two or three different brain cell types, in order to set an in vitro model of blood brain barrier, that may be useful for drug delivery studies, and for the formulation of new therapeutic strategies, to be used for the treatment of neurological diseases.