title: Up-regulated expression of MIF by interfacial membrane fibroblasts and macrophages around aseptically loosened implants.
abstract: BACKGROUND
  Local chronic inflammatory reaction plays an important role in the process of aseptic loosening of implants after total joint replacement. In addition, macrophage migration inhibitory factor (MIF) is a key upstream regulator of inflammation, and it is a significant regulator of inflammatory diseases. The purpose of this study is to investigate if the fibroblasts and macrophages in the interfacial membranes overexpress MIF.
  
  
  METHODS
  The 15 tissue samples of interfacial membranes were obtained from the tissues around the aseptically loosened femoral implants adjacent to osteolytic lesion in 15 patients. The 15 control synovial samples of hip joints were obtained from 15 patients who underwent primary hip arthroplasty because of the fresh fracture of the femoral neck. The levels of MIF protein and mRNA were evaluated by ELISA assay, immunofluorescence labeling, and real-time RT-PCR. Fibroblasts and macrophages were identified by immunofluorescence labeling.
  
  
  RESULTS
  The levels of MIF protein and mRNA were significantly increased, as well as the numbers of MIF+ fibroblasts and macrophages in the interfacial membranes compared with the control synovium.
  
  
  CONCLUSIONS
  Not only the macrophages, but also the fibroblasts in interfacial membranes overexpress MIF. MIF may play a significant role in the process of aseptic-loosening implants after total joint replacement.
authors.affiliation: Department of Orthopaedic Surgery, the Sixth Affiliated People's Hospital, Medical School of ShangHai JiaoTong University, Shanghai, China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Pan
authors.forename: Xin
authors.initials: X
authors.lastname: Mao
authors.forename: Tao
authors.initials: T
authors.lastname: Cheng
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Peng
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhongtang
authors.initials: Z
authors.lastname: Liu
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.forename: Yunsu
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D005260:Female; D005347:Fibroblasts / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006621:Hip Joint / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D019746:Intramolecular Oxidoreductases / Q000276:immunology* / Q000378:metabolism; D008263:Macrophage Migration-Inhibitory Factors / Q000276:immunology* / Q000378:metabolism; D008264:Macrophages / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D011475:Prosthesis Failure / Q000009:adverse effects*; D013583:Synovial Membrane / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015854:Up-Regulation / Q000276:immunology
chemical_list: D008263:Macrophage Migration-Inhibitory Factors; D019746:Intramolecular Oxidoreductases; C515598:MIF protein, human