title: Association of ferritin antibodies with Takayasu arteritis.
abstract: Takayasu arteritis (TA) is difficult to diagnose because diagnostic biomarkers have not yet been established. In a previous study, we detected autoantibodies against the human ferritin heavy chain protein (HFC) in the sera of patients with giant cell arteritis (GCA) and/or polymyalgia rheumatica (PMR). The aim of this study is to evaluate the frequency of autoantibodies against HFC in TA. We established seven ELISA assays for the detection of autoantibodies against HFC. We used the full-length recombinant HFC expressed in Escherichia coli or one of six different HFC peptides as autoantigens: 1-18Aa (98.8 % purity), 19-45Aa (98.8 % purity), 52-78Aa (98.3 % purity), 79-104Aa (98.8 % purity), 105-143Aa (98.4 % purity) and 145-183Aa (98.5 % purity). We collected sera from 48 patients with TA, 36 patients with systemic lupus erythematosus (SLE), 35 patients with arteriosclerosis, 133 patients with febrile diseases, which are known to generate unspecific autoantibodies, and 50 blood donors, which served as controls. The best results were obtained using the ferritin peptides as antigens. By combining the results from the different ELISAs that detect autoantibodies against the HFC peptides 19-44A, 79-104A and 105-144A, we were able to detect ferritin peptide antibodies in 30/48 (62 %) of the TA patients. The frequency was lower than in early GCA and PMR (previous study showed up to 92 %). Positive results were observed in 0/50 (0 %) of the control blood donors, 10/36 (28 %) of the SLE patients, 4/35 (11 %) of the arteriosclerosis patients and 27/133 (20 %) of the fever patients. Considering the lack of biomarkers for TA, autoantibodies against HFC peptides could act as useful markers for TA.
authors.affiliation: Department of Clinical Immunology and Rheumatology, Medical University Hannover, Carl-Neuberg Str. 1, 30625, Hannover, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Große
authors.forename: T
authors.initials: T
authors.lastname: Witte
authors.forename: F
authors.initials: F
authors.lastname: Moosig
authors.forename: B F
authors.initials: BF
authors.lastname: Hoyer
authors.forename: C
authors.initials: C
authors.lastname: Lansche
authors.forename: R E
authors.initials: RE
authors.lastname: Schmidt
authors.forename: N T
authors.initials: NT
authors.lastname: Baerlecken
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000097:blood*; D001052:Apoferritins / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D005334:Fever / Q000097:blood / Q000276:immunology; D013700:Giant Cell Arteritis / Q000097:blood / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011111:Polymyalgia Rheumatica / Q000097:blood / Q000276:immunology; D013625:Takayasu Arteritis / Q000097:blood / Q000175:diagnosis / Q000276:immunology*
chemical_list: D000906:Antibodies; D015415:Biomarkers; D001052:Apoferritins