title: The role of TLR and chemokine in wear particle-induced aseptic loosening.
abstract: Wear particle-induced periprosthetic osteolysis remains the principal cause of aseptic loosening of orthopaedic implants. Monocytes/macrophages phagocytose wear particles and release cytokines that induce inflammatory response. This response promotes osteoclast differentiation and osteolysis. The precise mechanisms by which wear particles are recognized and induce the accumulation of inflammatory cells in the periprosthetic tissue have not been fully elucidated. Recent studies have shown that toll-like receptors (TLRs) contribute to the cellular interaction with wear particles. Wear particles are recognized by monocytes/macrophages through TLRs coupled with the adaptor protein MyD88. After the initial interaction, wear particles induce both local and systemic migration of monocytes/macrophages to the periprosthetic region. The cellular migration is mediated through chemokines including interleukin-8, macrophage chemotactic protein-1, and macrophage inhibitory protein-1 in the periprosthetic tissues. Interfering with chemokine-receptor axis can inhibit cellular migration and inflammatory response. This paper highlights recent advances in TLR, and chemokine participated in the pathogenesis of aseptic loosening. A comprehensive understanding of the recognition and migration mechanism is critical to the development of measures that prevent wear particle-induced aseptic loosening of orthopaedic implants.
authors.affiliation: Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Orthopaedic Institute of Soochow University, 188 Shizi Road, Jiangsu, Suzhou 215006, China.
authors.forename: Qiaoli
authors.initials: Q
authors.lastname: Gu
authors.forename: Qin
authors.initials: Q
authors.lastname: Shi
authors.forename: Huilin
authors.initials: H
authors.lastname: Yang
mesh_terms: D000818:Animals; D002465:Cell Movement; D018925:Chemokines / Q000378:metabolism*; D006801:Humans; D019736:Prostheses and Implants / Q000009:adverse effects*; D011475:Prosthesis Failure / Q000209:etiology*; D015398:Signal Transduction; D051193:Toll-Like Receptors / Q000378:metabolism*
chemical_list: D018925:Chemokines; D051193:Toll-Like Receptors