{
  "abstract": "Immune-mediated outcomes diverge across individuals with similar genetic backgrounds and environmental exposures, reflecting trajectories through a dynamic, context-dependent, and partially stochastic state space rather than fixed molecular endpoints. Despite advances in systems immunology, computational modeling, and multi-omic profiling, translating this complexity into clinically actionable reasoning remains difficult: these disciplines generate increasingly detailed representations of immune behavior that deepen mechanistic understanding while raising barriers to integration across clinical, experimental, and computational domains. A clinician at the bedside cannot reason across tens of thousands of molecular variables, cell states, pathways, and contextual modifiers simultaneously. We adopt a reduction-oriented perspective — not because immune data are insufficient, but because high-dimensional biological information must be organized into a reduced representational space before it can support cross-domain reasoning. When a system is too complex to reason about directly, progress may depend on identifying a minimal set of variables that preserves explanatory power while enabling tractable inference. Rather than modeling the immune system in full mechanistic detail, we seek a constrained representation capturing the minimal structure necessary to characterize clinically observable immune phenotypes, consistent with principles from state-space modeling, dimensionality reduction, and systems biology. Here, we introduce ACT — Activation, Constraint, and Tissue Context — a reduced-dimensional immune phenotype space for reasoning about immune state across systemic and tissue-localized compartments. Within ACT, clinical observations, laboratory measurements, and multi-omic data are interpreted as projections of a latent immune state that evolves over time under environmental influence, host predisposition, therapeutic intervention, tissue context, and stochastic perturbation. Immune phenotype is thus represented not as a static label, but as a trajectory through reduced immune-state space. ACT does not infer molecular mechanism directly from phenotypic or reduced-state data. Instead, it provides a structured mapping from data to state, state to trajectory, and trajectory to pathway-level hypothesis generation — linking parsimonious state representation with trajectory-based reasoning to offer a conceptual scaffold for translating between clinical observation, multi-omic data, and pathway-level hypothesis generation in complex immune-mediated conditions. The goal is not to replace high-resolution molecular data, systems immunology, or mechanistic modeling, but to provide a common translational coordinate system for reasoning about immune phenotype across scales of observation and disciplinary boundaries — supporting communication, interpretation, and hypothesis generation across clinical, experimental, and computational domains.",
  "abstract_shown": true,
  "affiliations": [
    "Accenture",
    "Independent Researcher"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Jeffrey John Lorsung"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/491ajsnmnkr8z.bib",
  "cited_by": 0,
  "doi": "10.3389/fimmu.2026.1866922",
  "fulltext_url": "https://www.frontiersin.org/articles/10.3389/fimmu.2026.1866922/full",
  "id": "491ajsnmnkr8z",
  "issns": [
    "1664-3224"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fimmu.2026.1866922/full",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "RC581-607"
    ],
    [
      "openalex",
      "2403|T-cell and B-cell Immunology"
    ]
  ],
  "openalex": "W7223293809",
  "pdf_url": "https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2026.1866922/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/491ajsnmnkr8z.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:17Z",
      "native_id": "10.3389/fimmu.2026.1866922",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fimmu.2026.1866922/full"
    },
    {
      "first_seen": "2026-10-30T13:43:47Z",
      "native_id": "68bd960aa3c944d5adb4e385162c6a19",
      "source": "doaj",
      "url": "https://doi.org/10.3389/fimmu.2026.1866922"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "openalex:2403|T-cell and B-cell Immunology",
      "subfield": "immunology"
    }
  ],
  "title": "Bringing translational structure to complex immune-mediated conditions: the ACT (Activation–Constraint–Tissue Context) framework for divergent phenotypes",
  "title_text": "Bringing translational structure to complex immune-mediated conditions: the ACT (Activation–Constraint–Tissue Context) framework for divergent phenotypes",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:43:47Z",
  "url": "https://research.draconitic.com/paper/491ajsnmnkr8z",
  "venue": "Frontiers in Immunology",
  "versions": []
}