Autologous engineered cartilage rods for penile reconstruction

Purpose: Conditions such as inadequate and ambiguous genitalia that are cau sed by rudimentary penis, severe hypospadias or traumatic injury require su rgical intervention. Although silicone penile prostheses are an accepted tr eatment modality, biocompatibility issues may be a problem in select cases. We previously demonstrated that rods composed of cartilage could be create d using chondrocytes seeded on biodegradable polymer scaffolds. We showed t hat the cartilage rods engineered ex situ were readily elastic and withstoo d high degrees of pressure. We investigated the feasibility of applying the engineered cartilage rods in situ in an animal model. Materials and Methods: Autologous chondrocytes harvested from rabbit ears w ere grown and expanded in culture. Cells were seeded onto biodegradable pol y-L-lactic acid coated polyglycolic acid polymer rods at a concentration of 50 x 10(6) chondrocytes per cm.(3). A total of 18 chondrocyte polymer scaf folds were implanted into the corporal spaces in 10 rabbits. As controls, 1 corpus in each of 2 rabbits was not implanted. The animals were sacrificed 1, 2, 3 or 6 months after implantation. Histological analysis was performe d using hematoxylin and eosin, aldehyde fuschin-alcian blue and toluidine b lue staining. Results: All animals tolerated the implants for the duration of the study w ithout any complications. Gross examination after retrieval at I month show ed well formed, milky white cartilage structures within the corpora. All po lymers were fully degraded by 2 months. There was no evidence of erosion or infection at any of the implant sites. Histological analysis using alcian blue and toluidine blue staining revealed mature and well formed chondrocyt es in the retrieved implants. Conclusions: Autologous chondrocytes seeded on preformed biodegradable poly mer structures form cartilage structures within the rabbit corpus cavernosu m. This technology appears to be useful for creating autologous penile pros theses.