RT Journal A1 Shanbhag, Arun S. A1 Kaufman, Adam M. A1 Hayata, Koichiro A1 Rubash, Harry E. T1 Assessing Osteolysis with Use of High-Throughput Protein Chips JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 2007 FD May 1 VO 89 IS 5 SP 1081 OP 1089 DO 10.2106/JBJS.F.00330 UL http://dx.doi.org/10.2106/JBJS.F.00330 AB Background: Previous studies of bone resorption around failed joint replacements have focused on a limited number of cytokines, primarily tumor necrosis factor-a (TNF-a), interleukin (IL)-1, and IL-6, with use of enzyme-linked immunosorbent assay and immunohistochemistry techniques. In this study, we utilized high-throughput protein chips to profile twenty-nine inflammatory cytokines around failed total joint replacements.Methods: Peri-implant granulomatous tissues were harvested from around the failed total hip prostheses of thirteen patients. Synovial lining capsular tissues from thirteen patients with end-stage degenerative joint disease were used as controls. After homogenization, twenty-nine cytokines were quantified with use of high-throughput protein chips.Results: IL-6 and IL-8 were found consistently in failed joint replacement tissues, reaffirming their prominent role in osteoclastogenesis and end-stage bone resorption. High levels of interferon-?-inducible protein of 10 kDa (IP-10) and monokine induced by interferon-? (MIG), both chemoattractants of activated Th1 lymphocytes, were also detected. Soluble intercellular adhesion molecule (sICAM) and transforming growth factor-ß1 (TGF-ß1) were not detected universally, nor were TNF-a or IL-1. After a twenty-four-hour organ culture, IL-1ß levels increased substantially along with those of other mediators. We measured but did not detect any activators of cytotoxic T-cells, antibody-producing Bcells, or eosinophils involved in delayed-type hypersensitivity. Variations from patient to patient were seen across all cytokines and highlight the unique response of individual patients to their joint replacements.Conclusions: In failed total joint replacements in patients with end-stage osteolysis, IL-6 and IL-8 may be the primary drivers of osteoclastogenesis. The presence of IP-10 and MIG imply a role for T-cells, while TGF-ß1 and sICAM may represent a systemic attempt to modulate the inflammation. TNF-a and IL-1 do not appear to play a major role in the end stages of the disease.Clinical Relevance: These results demonstrate that proteomic tools can provide a foundation for understanding the cytokine-driven osteolysis cascade and a base from which to identify and evaluate potential targets for blockage or augmentation.