Morphological features of ovine embryonic lung fibroblasts cultured on different bioactive scaffolds

Tissue regeneration with autologous cell transplantation is one of the most important goals in clinical research. In this field, the development of bioactive materials that provide microenvironments for cell-matrix interactions mimicking biological conditions is required. In recent years, many synthetic materials have been developed as scaffolds and many procedures for the surface modification of these materials have been applied using biological molecules. In this study, we analyzed the morphology and the molecule production by ovine embryonic lung fibroblasts cultured on three different sponge-like matrices based on poly(L-lactic acid) (PLLA): agarose/PLLA, crosslinked and uncrosslinked gelatin/PLLA. The matrices were produced by using an emulsion freeze-drying method leading to the formation of sponge-like materials with high porosity and with interconnection between the pores. In vitro MTT test demonstrated that transplanted cells were viable and metabolically active. Morphological analysis revealed that fibroblasts adhered to and penetrated the polymeric structures. Moreover, all the different matrices supported fibroblast production of proteoglycans, glycoproteins, and matrix molecules such as elastin, collagen I, and fibronectin. These data suggest that the tested bioactive scaffolds may support the growth and extracellular matrix molecule production of fibroblasts allowing in vitro connective tissue regeneration.