Background: Ro52 is an interferon-inducible protein of the tripartite motif family. Antibodies against Ro52 have been described in patients with different autoimmune diseases, such as systemic lupus erythematosus and Sjögren's syndrome, that are often associated with anti-Ro60 antibodies. The Ro52 autoantigen is extraordinarily immunogenic, and its autoantibodies are directed against both linear and conformational epitopes. The aim of this study was to evaluate the prevalence of antibodies to the five Ro52 domains, as well as to Ro52 176- to 196-amino acid (aa) and 200-239-aa peptides, in different systemic autoimmune rheumatic diseases (SARDs). We also aimed to verify whether antibodies to a single domain or domain association could increase their diagnostic specificity for any SARD.
Methods: Serum samples were obtained from 100 anti-Ro52 antibody-positive patients with SARDs and from 68 controls (50 healthy donors and 18 patients with other autoimmune or allergic diseases). A special line immunoassay was created containing a full-length Ro52 antigen expressed in insect cells using the baculovirus system, five recombinant Ro52 antigen fragments [Ro52-1, Ro52-2, Ro52-3, Ro52-4 (partly overlapping Ro52-1 and Ro52-2), and Ro52-5 (partly overlapping Ro52-2 and Ro52-3)], and two Ro52 peptides (176-196 aa and 200-239 aa), all expressed in Escherichia coli.
Results: In patients with SARDs, fragment prevalence rates were as follows: Ro52-1 = 3 %, Ro52-2 = 97 %, Ro52-3 = 0 %, Ro52-4 = 9 %, Ro52-5 = 28 %, Ro52 175-196-aa peptide = 6 %, and Ro52 200-239-aa peptide = 74 %. All control samples were negative for the full-length Ro52 and for the five fragments tested.
Conclusions: The main epitope of the Ro52 antigen was localized on fragment 2 (aa 125-267), and the majority (97 %) of SARD sera had antibodies that target this fragment. As most of the samples were positive for fragment 2 and only some for fragments 4 or 5, which partially overlap fragment 2, it seems that the target epitope is localized in the middle of fragment 2 or in the area between fragments 4 and 5. No antibody against a single epitope or a combination of epitopes was linked to any of the single SARDs.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4704540 | PMC |
http://dx.doi.org/10.1186/s13075-015-0871-3 | DOI Listing |
Clin Rheumatol
January 2025
Department of Rheumatology and Immunology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
Objectives: This study aimed to evaluate the incidence and clinical significance of coexistence of anti-aminoacyl-tRNA synthetase (anti-ARS) antibody in patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis (anti-MDA5 + DM).
Methods: We assessed a cohort of 246 consecutive patients with anti-MDA5 + DM. Clinical characteristics and survival rates were compared between patients with and without anti-ARS antibodies.
Ann Med
December 2025
Department of Rheumatology and Immunology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
Objective: Anti-melanoma differentiation-associated gene 5-positive dermatomyositis-associated interstitial lung disease (MDA5DM-ILD) often leads to acute respiratory failure and endangers lives. This study quantitatively analysed chest high-resolution computed tomography (HRCT) images to assess MDA5DM-ILD and establish a risk prediction model for severe ILD within six months.
Methods: We developed a 'Standardized Threshold Ratio Analysis & Distribution' (STRAD) to analyse lung HRCT images.
Arthritis Res Ther
December 2024
Department of Rheumatology and Clinical Immunology, School of Medicine, The First Affiliated Hospital of Xiamen University, Xiamen University, 55 Zhenhai Road, Xiamen, XM, 361000, China.
Front Med (Lausanne)
November 2024
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, China.
Background: To identify risk factors for progression, acute exacerbation (AE), and the development of rapidly progressive interstitial lung disease (RP-ILD) in Systemic autoimmune rheumatic disease-associated interstitial lung disease (SARD-ILD).
Methods: We systematically searched PubMed, EMBASE, Scopus, the Cochrane Library, and Web of Science databases to identify eligible cohort studies up until January 01, 2024. Two reviewers independently screened the literature and extracted data.
Cureus
November 2024
Acute Medicine, Queen Alexandra Hospital, Portsmouth Hospital University NHS Trust, Portsmouth, GBR.
Dermatomyositis is a multi-system, connective tissue immune-mediated inflammatory condition characterised by myositis and distinct skin manifestations, with a higher prevalence in women. Symptoms typically appear in adulthood, though a juvenile form exists. Early signs may include Gottron's papules and heliotrope rash, with proximal muscle weakness as the second most common initial symptom.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!