Cell carriers as the next generation of cell therapy for cartilage repair: a review of the matrix-induced autologous chondrocyte implantation procedure.
BACKGROUND
Since the first patient was implanted with autologous cultured chondrocytes more than 20 years ago, new variations of cell therapies for cartilage repair have appeared. Autologous chondrocyte implantation, a first-generation cell therapy, uses suspended autologous cultured chondrocytes in combination with a periosteal patch. Collagen-covered autologous cultured chondrocyte implantation, a second-generation cell therapy, uses suspended cultured chondrocytes with a collagen type I/III membrane. Today's demand for transarthroscopic procedures has resulted in the development of third-generation cell therapies that deliver autologous cultured chondrocytes using cell carriers or cell-seeded scaffolds.


OBJECTIVE
To review the current evidence of the matrix-induced autologous chondrocyte implantation procedure, the most widely used carrier system to date. Also discussed are the characteristics of type I/III collagen membranes, behavior of cells associated with the membrane, surgical technique, rehabilitation, clinical outcomes, and quality of repair tissue.


METHODS
Systematic review.


METHODS
Relevant publications were identified by searching Medline from its inception (1949) to December 2007; peer-reviewed publications of preclinical and clinical cell behavior, manufacturing process, surgical technique, and rehabilitation protocols were identified. Preclinical and clinical studies were included if they contained primary data and used a type I/III collagen membrane.


RESULTS
Data from these studies demonstrate that patients treated with matrix-induced autologous chondrocyte implantation have an overall improvement in clinical outcomes. Reduced visual analog scale pain levels (range, 1.7-5.32 points) and improvements in the modified Cincinnati (range, 3.8-34.2 points), Lysholm-Gillquist (range, 23.09-47.6 points), Tegner-Lysholm (range, 1.39-3.9 points), and International Knee Documentation Classification scale (P <.05) were observed. Patients had good-quality (hyaline-like) repair tissue as assessed by arthroscopic evaluation (including International Cartilage Repair Society score), magnetic resonance imaging, and histology, as well as a low incidence of postoperative complications.


CONCLUSIONS
The findings suggest that matrix-induced autologous chondrocyte implantation is a promising third-generation cell therapy for the repair of symptomatic, full-thickness articular cartilage defects.
Brittberg
Mats
M
Kungsbacka Hospital Cartilage Research Unit, University of Gothenburg, Department of Orthopaedics, Kungsbacka Hospital, Kungsbacka, Sweden. mats.brittberg@telia.com
D001182:Arthroscopy; D002356:Cartilage / Q000637:transplantation; D002358:Cartilage, Articular / Q000601:surgery*; D064987:Cell- and Tissue-Based Therapy; D019902:Chondrocytes / Q000637:transplantation*; D024042:Collagen Type I / Q000627:therapeutic use; D024061:Collagen Type III / Q000627:therapeutic use; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D019637:Orthopedic Procedures / Q000379:methods; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D014481:United States
D024042:Collagen Type I; D024061:Collagen Type III