In on aspect, the invention includes a microcarrier bead having a porous three-dimensional core having (a) a polymeric porous three-dimensional body having porosity of about 15 to about 90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns, (b) an outer protective layer and optionally (c) a filler. In another aspect, the invention includes a method of making an artificial scaffold wherein a scaffolding material is extruded into a coolant and thereby creating a porous material having a porosity of between 15-90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns.