The Effect of Ultra-High Molecular Weight Polyethylene Wear Debris on MG63 Osteosarcoma Cells in Vitro

• Published in: Journal of bone and joint surgery. American volume 1999-04, Vol.81 (4), p.452-61
• Main Authors: DEAN, D D, SCHWARTZ, Z, LIU, Y, BLANCHARD, C R, AGRAWAL, C M, MABREY, J D, SYLVIA, V L, LOHMANN, C H, BOYAN, B D
• Format: Article
• Language: English
• Subjects: Adult; Alkaline Phosphatase - metabolism; Biological and medical sciences; Cell Division; Collagen - biosynthesis; Culture Media, Conditioned; Female; Hip Prosthesis; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Microscopy, Electron, Scanning; Middle Aged; Molecular Weight; Osteoarticular system. Muscles; Osteoblasts - pathology; Osteoblasts - physiology; Osteolysis - metabolism; Osteosarcoma - pathology; Particle Size; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Polyethylenes; Prosthesis Failure; Thymidine - metabolism; Tumor Cells, Cultured
• ISSN: 0021-9355; 1535-1386
• DOI: 10.2106/00004623-199904000-00002

BackgroundFocal osteolysis due to ultra-high molecular weight polyethylene wear debris involves effects on both bone resorption and bone formation. MethodsThe response of MG63 osteoblast-like osteosarcoma cells to ultra-high molecular weight polyethylene wear debris isolated by enzymatic digestion of granulomatous tissue obtained from the sites of failed total hip arthroplasties was examined. Scanning electron microscopy, particle-size analysis, and Fourier transform infrared spectroscopy were used to characterize the number, morphology, size distribution, and chemical composition of the particles. Cell response was assessed by adding particles at varying dilutions to confluent cultures and measuring changes in cell proliferation (number of cells and [H]-thymidine incorporation), osteoblast function (alkaline-phosphatase-specific activity and osteocalcin production), matrix production (collagen production and proteoglycan sulfation), and local cytokine production (prostaglandin-E2 production). ResultsThe mean size of the particles was 0.60 micrometer, and 95 percent of the particles had a size of less than 1.5 micrometers. The number of particles per gram of tissue ranged from 1.39 to 3.38 x 10. Three of the four batches of particles were endotoxin-free. Exposure of the cells to particles of wear debris significantly increased the number of cells (p < 0.05) and the [H]-thymidine incorporation (p < 0.05) in a dose-dependent manner. In contrast, the addition of particles decreased alkaline-phosphatase-specific activity and osteocalcin production. Collagen production and proteoglycan sulfation were also decreased, while prostaglandin-E2 synthesis was increased by the addition of particles. ConclusionsUltra-high molecular weight polyethylene particles isolated from human tissue stimulated osteoblast proliferation and prostaglandin-E2 production and inhibited cell differentiation and matrix production. These results indicate that particles of wear debris inhibit cell functions associated with bone formation and that osteoblasts may produce factors in response to wear debris that influence neighboring cells, such as osteoclasts and macrophages. Clinical RelevanceParticles of wear debris, especially ultra-high molecular weight polyethylene, have been implicated in the loosening of implants and the development of osteolysis. The present study shows that particles of ultra-high molecular weight polyethylene isolated from human tissue inhibit osteoblast functions as