Influence of mouse genetic background on wear particle-induced in vivo inflammatory osteolysis

OBJECTIVE AND DESIGN: Genetics may influence wear particle-induced inflammatory osteolysis after joint replacement. In the present work, mice with three different genetic backgrounds were used to test this hypothesis. TREATMENT: C57BL/6J, Balb/c and Kunming mouse were used. Each kind of mouse was divided into those receiving 30 mg UHMWPE particle implantation onto the calvariae and those receiving a sham operation. METHODS: Mice of each group were sacrificed one week after surgery. Calvariae were harvested for immunological assay of TNF-alpha and IL-1 beta secretion in supernatants of calvariae organ culture and histological analysis of calvarial sagittal suture osteolysis and osteoclastogenesis. RESULTS: Although UHMWPE particles induced obvious calvarial sagittal suture osteolysis and osteoclastogenesis in all strains as compared with their corresponding control mice, the most significant change was found in C57BL/6J mice, less severe in Balb/c mice and much less severe in Kunming mice. In agreement with pathological findings, UHMWPE particles induced the highest IL-1 beta secretion in C57BL/6J mice, compared with Balb/c and Kunming mice. However, no difference was observed concerning TNF-alpha secretion among these mice. CONCLUSION: Our data suggests that genetics had a significant influence on wear particle-induced inflammation, osteoclastogenesis and osteolysis. The influence of genetic background on implant life in patients with joint replacement warrants further investigation.