title: The correlation of RANK, RANKL and TNFalpha expression with bone loss volume and polyethylene wear debris around hip implants.
abstract: This study investigates receptor activator NF-kappaB (RANK), RANK ligand (RANKL) and tumour necrosis factor (TNFalpha), key factors regulating bone turnover, present in the tissues near peri-prosthetic osteolysis. Tissue was obtained from zones of peri-prosthetic osteolysis from 11 patients undergoing revision of total hip prostheses, analysed preoperatively by high-resolution spiral multislice CT using a metal artefact suppression protocol. Synovial tissue from 10 patients with osteoarthritis undergoing primary hip replacement was used as control tissue. Immunohistochemical analysis of formalin fixed tissue sections demonstrated that RANK, RANKL and TNFalpha were strongly expressed by large multinucleated cells containing polyethylene wear debris in revision tissues. Control tissue stained weakly for RANK, RANKL and TNFalpha. A strong statistical correlation (p<0.02) was found between the five parameters, volume of bone loss, polyethylene wear debris, RANK, RANKL and TNFalpha expression. Importantly, in vitro studies revealed that RANKL and TNFalpha synergise to increase the volume of bone resorbed, by more than seven fold, when compared to the effect of either cytokine treatment alone. This suggests that the interaction of TNFalpha and RANKL promotes osteoclast activity associated with polyethylene wear and therapies targeting TNF activity may be useful to treat peri-implant osteolysis.
authors.affiliation: Department of Pathology, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Holding
authors.forename: David M
authors.initials: DM
authors.lastname: Findlay
authors.forename: Roumen
authors.initials: R
authors.lastname: Stamenkov
authors.forename: Susan D
authors.initials: SD
authors.lastname: Neale
authors.forename: Helen
authors.initials: H
authors.lastname: Lucas
authors.forename: A S S K
authors.initials: AS
authors.lastname: Dharmapatni
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Callary
authors.forename: Kush R
authors.initials: KR
authors.lastname: Shrestha
authors.forename: Gerald J
authors.initials: GJ
authors.lastname: Atkins
authors.forename: Donald W
authors.initials: DW
authors.lastname: Howie
authors.forename: David R
authors.initials: DR
authors.lastname: Haynes
mesh_terms: D019644:Arthroplasty, Replacement, Hip; D001862:Bone Resorption / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D002352:Carrier Proteins / Q000032:analysis*; D006023:Glycoproteins / Q000032:analysis*; D006615:Hip / Q000000981:diagnostic imaging / Q000473:pathology; D006622:Hip Prosthesis; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000032:analysis*; D010010:Osteoclasts / Q000276:immunology; D010014:Osteolysis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D053244:Osteoprotegerin; D011095:Polyethylenes / Q000378:metabolism; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis*; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis*; D014057:Tomography, X-Ray Computed; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis* / Q000502:physiology
chemical_list: D002352:Carrier Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D011095:Polyethylenes; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; D014409:Tumor Necrosis Factor-alpha