Researchers at Weill Cornell Medicine and Cornell Engineering have utilized advanced tissue engineering methods and a 3D printer to construct a lifelike replica of an adult human ear. Published online in Acta Biomaterialia, the study offers hope for individuals with congenital ear malformations or those who have lost an ear later in life, providing grafts with precise anatomy and appropriate biomechanical properties (1).

Traditional Method of Ear Grafts

Traditionally, surgeons have crafted replacement ears using cartilage from a child’s ribs, a procedure that can be painful and leave scars. While the resulting grafts can resemble the recipient’s other ear, they often lack the same flexibility.

Realistic Ear Replica Using Chondrocytes

To create a more natural replacement ear, researchers turned to chondrocytes, the cells responsible for building cartilage. Previous attempts using animal-derived chondrocytes seeded onto a collagen scaffold initially succeeded but eventually lost the ear’s distinctive features due to contraction caused by cell activity. In this study, researchers utilized sterilized animal-derived cartilage treated to minimize immune rejection. Loaded into intricate, ear-shaped plastic scaffolds created on a 3D printer based on ear data from a recipient, the cartilage acted as internal reinforcements, preventing contraction and encouraging new tissue formation.

How Similar is the Novel Ear Replica to Human Ear?

Over three to six months, the structure developed cartilage tissue closely resembling the ear’s anatomical features, including the helical rim, anti-helix rim, and central conchal bowl. Biomechanical studies confirmed the replicas’ flexibility and elasticity similar to human ear cartilage, although they were not as strong and could tear. To enhance strength, researchers plan to incorporate recipient-derived chondrocytes, which produce elastic proteins, into future grafts.

References:

1. Bioengineering Full-scale Auricles Using 3D-printed External Scaffolds and Decellularized Cartilage Xenograft
   
   Vernice, N. A., et al. (2024). Bioengineering Full-scale Auricles Using 3D-printed External Scaffolds and Decellularized Cartilage Xenograft. Acta Biomaterialia. doi.org/10.1016/j.actbio.2024.03.012.

Source-Medindia