{
  "abstract": "Annual influenza vaccination is recommended after allogeneic hematopoietic cell transplantation (HCT), but antibody responses vary widely. We asked whether pre-vaccination immune-cell composition predicts the antibody response beyond baseline titers and clinical factors. We studied the first vaccination season of 260 participants in 2 multicenter phase 2 trials of high- versus standard-dose influenza vaccine, 1 pediatric and 1 adult, and held out for validation 74 second-season episodes from participants who re-enrolled the following year. Thirty-marker mass cytometry measured blood cell composition, and models predicted the mean antibody log fold-rise across 3 antigens in recipients left out of nested cross-validation. Adding immune-cell composition to baseline antibody titers reduced mean squared prediction error by 15.3% (95% CI, 7.0-23.2%; P < .001), and adding it to titers plus clinical factors by 12.5% (4.6-20.3%; P = .001). A cellular composition score identified recipients unlikely to respond: in its lowest fifth, 15% had a fourfold antibody rise against 51% of the others. At a given baseline titer, each standard deviation of the score about doubled the odds of a fourfold rise (odds ratio, 2.2; P = .007), in children and adults alike; low scores reflected fewer B cells and more monocytes. In the held-out second season, composition reduced prediction error by 39%, and prediction was similar with 15 markers. Pre-vaccination immune-cell composition therefore predicts influenza vaccine immunogenicity after HCT, and simpler assays merit prospective validation. The trials are registered at www.clinicaltrials.gov as #NCT02860039 (pediatric) and #NCT03179761 (adult).",
  "abstract_shown": true,
  "affiliations": [
    "Vanderbilt University Medical Center"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "A. Asiaee"
    },
    {
      "name": "S. Pal"
    },
    {
      "name": "J. D. Simmons"
    },
    {
      "name": "A. J. Spieker"
    },
    {
      "name": "J. D. Chappell"
    },
    {
      "name": "N. B. Halasa"
    },
    {
      "affs": [
        0
      ],
      "name": "S. A. Kalams"
    },
    {
      "name": "Influenza Vaccine in HCT Study Group"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ej7f64z1pjvrw.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.11.01.26367040",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.11.01.26367040v1.full",
  "id": "ej7f64z1pjvrw",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.11.01.26367040v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "infectious diseases"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.11.01.26367040v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ej7f64z1pjvrw.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:20Z",
      "native_id": "10.64898/2026.11.01.26367040",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.11.01.26367040v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:infectious diseases",
      "subfield": "infectious-disease"
    }
  ],
  "title": "Deep immune cell phenotyping predicts influenza vaccine immunogenicity in HCT recipients",
  "title_text": "Deep immune cell phenotyping predicts influenza vaccine immunogenicity in HCT recipients",
  "type": "preprint",
  "updated_at": "2026-11-04T00:21:02Z",
  "url": "https://research.draconitic.com/paper/ej7f64z1pjvrw",
  "venue": "medRxiv",
  "versions": []
}