{
  "abstract": "BackgroundPersistent SARS-CoV-2 antigen is a leading hypothesis for post-acute sequelae of SARS-CoV-2 infection (PASC), commonly known as Long COVID. Impaired Fc-mediated antiviral antibody function could contribute to inefficient clearance of infected cells and viral antigen despite preserved antibody levels. Therefore, we tested whether PASC is associated with altered Fc{gamma} receptor-mediated antibody function and differences in IgG1 Fc fucosylation, a major regulator of Fc effector function.\n\nMethodsSerum samples from RECOVER-Adult participants with prior SARS-CoV-2 infection (99 PASC, 139 non-PASC) were analyzed for anti-SARS-CoV-2 spike receptor-binding domain (RBD) IgG and subclasses, Fc{gamma}RIIIa- and Fc{gamma}RIIa-mediated reporter activity as surrogate measures of antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP), anti-RBD IgG1 Fc glycosylation, and circulating fucose-modifying enzymes.\n\nResultsDespite higher anti-RBD IgG and IgG1 abundance, PASC sera showed lower ADCC- and ADCP-associated Fc{gamma}R reporter activity, including after normalization for antibody abundance. Anti-RBD IgG1 showed greater fucosylation in PASC samples (30 PASC, 34 non-PASC). Serum FUCA2 was lower in PASC samples (24 PASC, 34 non-PASC), whereas FUCA1 and soluble CD16a levels did not differ between the two groups.\n\nConclusionPASC is associated with impaired antiviral IgG Fc function, increased IgG1 Fc fucosylation, and reduced circulating FUCA2, identifying a glycoimmune axis that may contribute to impaired Fc-dependent antigen clearance and represents a potentially targetable pathway in Long COVID.",
  "abstract_shown": true,
  "affiliations": [
    "Rutgers University"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "name": "R. Ukey"
    },
    {
      "name": "I. E. Michailidis"
    },
    {
      "name": "P. Greenberg"
    },
    {
      "name": "T. Andrews"
    },
    {
      "name": "S. Y. Jung"
    },
    {
      "name": "H. Zheng"
    },
    {
      "name": "W. Honnen"
    },
    {
      "name": "A. Pinter"
    },
    {
      "name": "L. C. Kleinman"
    },
    {
      "name": "N. Bruiners"
    },
    {
      "affs": [
        0
      ],
      "name": "m. l. gennaro"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1nk0pd416nc64.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.09.28.26364044",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.09.28.26364044v1.full",
  "id": "1nk0pd416nc64",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.09.28.26364044v1",
  "language": null,
  "licence": "CC-BY-ND",
  "licence_label": "CC BY-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "infectious diseases"
    ],
    [
      "openalex",
      "2728|Long-Term Effects of COVID-19"
    ]
  ],
  "openalex": "W7214751819",
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.09.28.26364044v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1nk0pd416nc64.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:40Z",
      "native_id": "10.64898/2026.09.28.26364044",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.09.28.26364044v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:infectious diseases",
      "subfield": "infectious-disease"
    }
  ],
  "title": "Antiviral Antibody Fc Dysfunction Is Linked to Increased IgG1 Fucosylation in Long COVID",
  "title_text": "Antiviral Antibody Fc Dysfunction Is Linked to Increased IgG1 Fucosylation in Long COVID",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:40Z",
  "url": "https://research.draconitic.com/paper/1nk0pd416nc64",
  "venue": "medRxiv",
  "versions": []
}