gms | German Medical Science

Objectives: As compared to commonly used cell based treatments for articular cartilage repair, grafting of cartilage tissues, engineered in vitro to reach a mature stage, could result in more durable repair. To reduce the variability in the quality of the engineered tissue grafts, nasal chondrocytes were used as a cell source with reproducible chondrogenic capacity. The purpose of this phase-1 study was to demonstrate safety and feasibility of the procedure. Preliminary indications on efficacy after 12 months are also presented.

Methods: Ten patients with symptomatic, post-traumatic full-thickness cartilage lesions (2-8cm2) on the femoral condyle/ trochlea were treated. Patients underwent nasal septum cartilage biopsy in an outpatient procedure. Autologous nasal chondrocytes were isolated, expanded, seeded and cultured in collagen sponges (Chondrogide®, Geistlich) according to Good Manufacturing Practice (GMP) regulations. After four weeks production, the engineered nasal cartilage graft was implanted via mini-arthrotomy.

Patients were followed up radiologically by MRI (MOCART score), delayed Gadolinium Enhanced MRI (dGEMRIC, for assessment of glycosaminoglycans content) and clinically (IKDC score).

Results and Conclusion: No complications occurred by nasal cartilage biopsying or implantation of the engineered tissues.

6 patients with 8 cartilage defects reached 12 months follow up so far. One patient with 1 defect partially lost the graft due to new sports injury and was excluded from analysis. The MOCART score 12 months post surgery was 32.5 (5-55). The dGEMRIC revealed a relative Delta R1 of 1.50 (0.78-2.17). The IKDC pre-surgery and 12 months post-surgery was 58.6 and 78.6 respectively.

These early results demonstrate safety and feasibility of the method and indicate that engineered nasal cartilage grafts can participate to the repair of articular cartilage defects in the knee. The mean relative Delta R1 of 1.50 (1.0 for native cartilage) suggests that hyaline repair tissue can be achieved, possibly to a higher extent than MACT (2.18, Trattnig+, 2008) or ACT (2.40, Trattnig+, 2007). Our results demonstrate safety and feasibility of the method and indicate that patients can benefit from this therapy.

This study opens a new approach in biological cartilage regeneration, based on engineering of mature cartilage tissues using autologous nasal chondrocytes.