title: Interface membrane fibroblasts around aseptically loosened endoprostheses express MMP-13.
abstract: The objective of this article was to assess whether matrix metalloproteinase-13 (MMP-13) is produced by cells of the peri-implant interface tissues and to further characterize these cells. Tissue specimens were collected from the bone-prosthesis interface at the time of revision surgery of clinically loosened hip and knee arthroplasties (n = 27). Synovial tissues from osteoarthritic patients and young patients with mild joint deformity were used as controls (n = 6). Tissue samples were fixed in 4% PFA, decalcified with EDTA, and embedded in paraffin. Sections (4 microm) were stained with hematoxylin/eosin and for the osteoclastic marker enzyme tartrate resistant acid phosphatase. Monocytes/macrophages were characterized with a monoclonal antibody against CD68 and mRNAs encoding MMP-13 and alpha(1) collagen I (COL1A1) were detected by in situ hybridization. Cells expressing transcripts encoding MMP-13 were found in 70% of the interface tissues. These cells colocalized with a cell population expressing COL1A1 mRNA, and were fibroblastic in appearance. MMP-13 expressing cells were found in the close vicinity of osteoclasts and multinuclear giant cells. No signals for transcripts encoding MMP-13 were detected in multinuclear giant cells or in osteoclasts. Control tissues were negative for transcripts encoding MMP-13 mRNA. Fibroblasts of the interface from aseptically loosened endoprostheses selectively express MMP-13. By the expression and the release of MMP-13, these fibroblastic cells may contribute to the local degradation of the extracellular matrix and to bone resorption.
authors.affiliation: Department of Orthopaedic Surgery, Klinikum Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr. 15, 81377 Munich, Germany. susanne.wagner@med.uni-muenchen.de
authors.forename: Susanne
authors.initials: S
authors.lastname: Wagner
authors.forename: Hans
authors.initials: H
authors.lastname: Gollwitzer
authors.forename: Dirk
authors.initials: D
authors.lastname: Wernicke
authors.forename: Rupert
authors.initials: R
authors.lastname: Langer
authors.forename: Klaus A
authors.initials: KA
authors.lastname: Siebenrock
authors.forename: Willy
authors.initials: W
authors.lastname: Hofstetter
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000096:biosynthesis; D015214:Antigens, Differentiation, Myelomonocytic / Q000096:biosynthesis; D001862:Bone Resorption; D002462:Cell Membrane / Q000378:metabolism*; D024042:Collagen Type I / Q000096:biosynthesis; D000090602:Collagen Type I, alpha 1 Chain; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000378:metabolism*; D005786:Gene Expression Regulation; D006622:Hip Prosthesis; D006801:Humans; D007720:Knee Prosthesis; D008264:Macrophages / Q000378:metabolism; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000096:biosynthesis*; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D011475:Prosthesis Failure; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D053509:Matrix Metalloproteinase 13; C067980:CD68 antigen, human; D000097382:CD68 Molecule