{
  "abstract": "Objectives: Emerging evidence supports the presence of autoantibodies targeting interleukin-1 receptor antagonist (IL-1Ra), a regulator of IL-1 signaling, in adult-onset Still’s disease (AOSD). However, existing data are limited by small cohorts and potential confounding due to prior exposure to IL-1 inhibitors. This study aimed to develop a simple and reproducible indirect ELISA for detecting anti-IL-1Ra antibodies and to assess their frequency and immunological features in IL-1 inhibitor-naïve AOSD patients.\n\nMethods: Serum samples from IL-1 inhibitor-naïve AOSD patients (n=46) and healthy controls (n=26) were analyzed using an indirect ELISA based on recombinant IL-1Ra (anakinra) as antigen. Specificity was confirmed by dot blot. Anti-IL-1Ra IgG were affinity-purified from a high-titer patient and characterized by ELISA and SDS-PAGE. Epitope mapping was performed using phage display peptide libraries, followed by sequence alignment and structural mapping onto native IL-1Ra.\n\nResults: Anti-IL-1Ra antibody levels were significantly higher in AOSD patients than in healthy controls (p=0.003), with a greater proportion showing high titers (p<0.001). Levels did not differ between active and inactive AOSD patients. Purified antibodies displayed specific dose-dependent binding to IL-1Ra. Phage display identified two peptide motifs corresponding to linear epitopes mapped to surface-exposed regions of the native protein, indicating recognition of unmodified IL-1Ra domains.\n\nConclusions: Anti-IL-1Ra antibodies are detectable in IL-1 inhibitor-naïve AOSD patients using a standardized ELISA. The identification of distinct linear epitopes suggests a heterogeneous autoimmune response targeting IL-1Ra and may support a role for adaptive immunity within the Still’s disease spectrum. Further studies are needed to define their functional and clinical relevance.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila , ,",
    "Rheumatic and Systemic Autoimmune Diseases Unit, Department of Interdisciplinary Medicine, University of Bari Medical School , ,",
    "Fondazione Policlinico Universitario , ,"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Piero Ruscitti"
    },
    {
      "affs": [
        1
      ],
      "name": "Elvira Favoino"
    },
    {
      "affs": [
        0
      ],
      "name": "Federica Viapiano"
    },
    {
      "affs": [
        0
      ],
      "name": "Giulia Sgarlata"
    },
    {
      "affs": [
        2
      ],
      "name": "Marta Vomero"
    },
    {
      "affs": [
        2
      ],
      "name": "Letizia Pia Di Corcia"
    },
    {
      "affs": [
        0
      ],
      "name": "Francesco Maria Mariani"
    },
    {
      "affs": [
        0
      ],
      "name": "Paola Cipriani"
    },
    {
      "affs": [
        2
      ],
      "name": "Roberto Giacomelli"
    },
    {
      "affs": [
        1
      ],
      "name": "Federico Perosa"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/edpjrk2gy7de0.bib",
  "cited_by": 0,
  "doi": "10.3389/fimmu.2026.1957327",
  "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13672321/?tool=EBI",
  "id": "edpjrk2gy7de0",
  "issns": [
    "1664-3224"
  ],
  "landing_url": "https://europepmc.org/article/PMC/PMC13672321",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2720|Autoimmune and Inflammatory Disorders Research"
    ]
  ],
  "openalex": "W7216278914",
  "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13672321/pdf/?tool=EBI",
  "pmcid": "PMC13672321",
  "pmid": null,
  "published": "2026-10-02",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/edpjrk2gy7de0.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:18Z",
      "native_id": "PMC:PMC13672321",
      "source": "europepmc",
      "url": "https://europepmc.org/article/PMC/PMC13672321"
    },
    {
      "first_seen": "2026-10-30T12:19:15Z",
      "native_id": "10.3389/fimmu.2026.1957327",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fimmu.2026.1957327/full"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "issn:1664-3224",
      "subfield": "immunology"
    }
  ],
  "title": "Autoantibodies against interleukin-1 receptor antagonist in Still’s disease in adult patients, data from a multicenter cohort study",
  "title_text": "Autoantibodies against interleukin-1 receptor antagonist in Still’s disease in adult patients, data from a multicenter cohort study",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:15Z",
  "url": "https://research.draconitic.com/paper/edpjrk2gy7de0",
  "venue": "Frontiers in immunology",
  "versions": []
}