title: Authors' reply.
authors.affiliation: Department of Rheumatology and Immunology, Peking University People's Hospital , Beijing , China.
authors.forename: X
authors.initials: X
authors.lastname: Sun
authors.forename: Z
authors.initials: Z
authors.lastname: Li
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D010003:Osteoarthritis / Q000276:immunology*; D010456:Peptides, Cyclic / Q000276:immunology*; D012217:Rheumatoid Factor / Q000276:immunology*; D013582:Synovial Fluid / Q000378:metabolism*; D053380:Tumor Necrosis Factor Ligand Superfamily Member 15 / Q000097:blood*
chemical_list: D001323:Autoantibodies; D010456:Peptides, Cyclic; D053380:Tumor Necrosis Factor Ligand Superfamily Member 15; D012217:Rheumatoid Factor