ABSTRACT
An important limitation in cell therapy for the regeneration of tissue is the initial lack of oxygen. After implantation of large 3D cell-seeded structures, cells die rather than contribute to tissue regenerating. Here we've tested oxygen-releasing materials to improve cell survival and growth after implantation. Calcium peroxide (CaO2) in a polymer matrix was used as source of oxygen. Two polymers were tested in order to slow down and extend the period of oxygen release, poly(D,L-lactic acid) and poly(lactic-co-glycolic acid). Compared to CaO2 particles, both releasing systems showed an initially higher and shorter oxygen release. Human mesenchymal stromal cells cultured on casted films of these oxygen-releasing composites required catalase to proliferate, indicating the production of cytotoxic hydrogen peroxide as intermediate. Poly(D,L-lactic acid) and poly(lactic-co-glycolic acid) are less suited for slowly oxygen-releasing materials. Catalase was able to reduce the cytotoxic effect of H2O2.
