Ear Cartilage Reconstruction Combining Induced Pluripotent Stem Cell-Derived Cartilage and Three-Dimensional Shape-Memory Scaffold

Microtia is a congenital malformation of the auricle. The conventional therapy for microtia is reconstruction of the auricle by using the patient's own costal cartilage. Because it is invasive to harvest costal cartilages, less invasive ways for auricular reconstruction need to be established. Recent reports have indicated a new method for the production of cartilaginous particles from human induced pluripotent stem cells. To adopt this method to create an auricular-shaped regenerative cartilage, a novel scaffold with the property of a three-dimensional shape memory was created. A scaffold with a three-dimensional shape of auricular frames composed of a helix and an antihelix, which was designed to mimic an auricular framework carved from autologous costal cartilage and transplanted in auricular reconstruction, was prepared, filled with cartilaginous particles, and subcutaneously transplanted in nude rats. The auricular-shaped regenerative cartilage maintained the given shape and cartilage features in vivo for 1 year. Our findings suggest a novel approach for auricular reconstruction. A recent report that indicated the production of cartilaginous particles from human induced pluripotent stem cells will provide the solution to overcome the limitation of a cell source for cartilage regeneration of large and complicated shapes such as auricles. By combining cartilaginous particles and a novel scaffold with the property of a three-dimensional shape memory, we fabricated auricular frames composed of a helix and an antihelix, which was designed to mimic an auricular framework carved from autologous costal cartilage in auricular reconstruction. Our findings demonstrate a novel approach for auricular reconstruction.