title: Immune Mediators in Osteoarthritis: Infrapatellar Fat Pad-Infiltrating CD8+ T Cells Are Increased in Osteoarthritic Patients with Higher Clinical Radiographic Grading.
abstract: Osteoarthritis is a condition of joint failure characterized by many pathologic changes of joint-surrounding tissues. Many evidences suggest the role of both innate and adaptive immunity that interplay, resulting either in initiation or in progression of osteoarthritis. Adaptive immune cells, in particular T cells, have been demonstrated to play a role in the development of OA in animal models. However, the underlying mechanism is yet unclear. Our aim was to correlate the frequency and phenotype of tissue-infiltrating T cells in the synovial tissue and infrapatellar fat pad with radiographic grading. Our results show that CD8+ T cells are increased in osteoarthritic patients with higher radiographic grading. When peripheral blood CD8+ T cells were examined, we show that CD8+ T cells possess a significantly higher level of activation than its CD4+ T cell counterpart (P< 0.0001). Our results suggest a role for CD8+ T cells and recruitment of these activated circulating peripheral blood CD8+ T cells to the knee triggering local inflammation within the knee joint.
authors.affiliation: Department of Orthopedics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Jirun
authors.initials: J
authors.lastname: Apinun
authors.affiliation: Immunology Division, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Panjana
authors.initials: P
authors.lastname: Sengprasert
authors.affiliation: Department of Orthopedics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Pongsak
authors.initials: P
authors.lastname: Yuktanandana
authors.affiliation: Department of Orthopedics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Srihatach
authors.initials: S
authors.lastname: Ngarmukos
authors.affiliation: Department of Orthopedics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Aree
authors.initials: A
authors.lastname: Tanavalee
authors.affiliation: Immunology Division, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Center of Excellence in Immunology and Immune-Mediated Diseases, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Rangsima
authors.identifier: 0000-0002-7747-8059
authors.initials: R
authors.lastname: Reantragoon