WEB Key factors for successful engineering of ovarian tissue: scaffold morphology vs biomaterial selection
Tissue engineering for reproductive organs is a topic which gained the interest of the scientific community in the last years, mainly because of the impact on health and quality of life of the patients, in particular for pediatric oncological patients. Electrospun fibers mimic not only the morphology of the native extra cellular matrix, but also the morphology of medulla and ovarian cortex. Starting from this biomimetic approach, the use of electrospun scaffolds have been proposed for supporting three dimensional culture of ovarian follicles, providing morphological and chemical signals. Previous studies also confirmed that it is fundamental for the ovarian follicles functionality to keep the three dimensional spherical shape which is usually affected by the substrate of culture. Moreover, in the perspective of implantation of seeded scaffolds into patients, it is also important that the follicles adhere and interact in a positive way with the substrate. For this reason, we demonstrate that the fibrillary substrate, constituted by electrospun fibers, provides the proper anchoring for ovarian follicles on the scaffolds, without altering their three dimensional spherical shape. For those experiments porcine ovarian follicles were used considering the porcine model closer to the human model in terms of follicles size and development period. Moreover, several tests have been performed in order to check if the average fiber diameter and fiber orientation (random versus a pattern with macropores of 300um) are able to interfere with follicles adhesion and vitality. Also, mouse ovarian follicles have been evaluated in order to compare the obtained results with the existing literature. As control biomaterials, poly(epsilon caprolactone), widely used for the electrospinning has been selected. Moreover, its blend with gelatin and chitosan have also been evaluated and the blended fibers have been tested. For all the electrospinning process only benign solvents for the electrospinning have been used. Different average fiber diameter range has been obtained for the blended fibers and their influence on follicles adhesion and vitality have been evaluated. Positive results have been obtained in terms of follicles vitality on all the random oriented scaffolds, although significant differences have been showed for the blended sampled, demonstrating that the ovarian mouse follicles are more sensitive to the biomaterials than to the morphology.