Autologous Chondrocyte Implantation: Overview
Despite advances in materials science and innovations in knee repair, no current therapy can mimic the extraordinary biomechanical properties of cartilage. This notion drives initiatives in cell-based replacement technologies. Autologous Chondrocyte Implantation (ACI) is the most refined of these techniques. The therapy implants millions of the patient’s own chondrocytes, which have been cultured from a biopsy sample. In the United States, Genzyme Corporation provides the only FDA approved ACI treatment, Carticel. Though Carticel is not widespread in patient demographics, results suggest that some patients can return to preinjury function and develop hyaline cartilage. Since the patients use their own cells, disease transmission risk is minimized. Future techniques in cell-based therapies will integrate the current technology with the emerging field of tissue engineering.
History of Autologous Cultured Chondrocyte Implantation
The rationale for autologous cultured chondrocyte implantation came from the unique biomechanical properties of cartilage and the ineffectiveness of other cartilage repair treatments.
1965 AudreySmith was the first to culture chondrocytes in vitro.
1984 Peterson et al developed the technique for autologous chondroctye implantation in rabbits. The experiment was subsequently studied in the canine model and other mammals.
1987 First autologous chondrocyte implantation in a human is done in Goteberg, Sweden
1994 Autologous chondrocyte transplantation was used to treat cartilage defects of 23 patients by Brittberg et al. Their results were the first in a human model and indicated that the ACI therapy could be used to repair deep cartilage defects in the femorotibilar articular surface of the knee joint.
1995 Carticel was introduced and became the first biologic product in the orthopedic treatments.
1997 Genzyme Biosurgery, producer of Carticel received accelerated FDA approval for implantation in the knee and became widely available to patients.
2005 Genzyme Corporation acquired Virigen AG, the producer of matrix-induced autologous chondrocyte implantation (MACI) technology, for $50 million.