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    "story_id": "mp-2026-07-26-008",
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    "headline": "A Missing Protein Stops White Blood Cells From Growing Up",
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    "dek": "Zebrafish and leukemia-cell experiments place progranulin beside JAK2-STAT3 signaling in the maturation of myeloid immune cells.",
    "summary": "Zebrafish and leukemia-cell experiments place progranulin beside JAK2-STAT3 signaling in the maturation of myeloid immune cells.",
    "body_text": "Iowa State University researchers report that progranulin and an active JAK2-STAT3 pathway are both required for myeloid progenitor cells to mature into macrophages. In zebrafish, disrupting the pathway impaired development; in selected human leukemia cell lines with the relevant signaling active, adding progranulin pushed cells toward a more mature state. Those preclinical results expose a mechanism worth testing, not a leukemia treatment ready for patients, and the generic glassware image does not depict the work.",
    "why_it_matters": "Zebrafish and leukemia-cell experiments place progranulin beside JAK2-STAT3 signaling in the maturation of myeloid immune cells.",
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      "Those preclinical results expose a mechanism worth testing, not a leukemia treatment ready for patients, and the generic glassware image does not depict the work."
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        "text": "Zebrafish and leukemia-cell experiments place progranulin beside JAK2-STAT3 signaling in the maturation of myeloid immune cells.",
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        "qualification": "Those preclinical results expose a mechanism worth testing, not a leukemia treatment ready for patients, and the generic glassware image does not depict the work."
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    "tags": [
      "progranulin",
      "myeloid cells",
      "JAK2-STAT3",
      "leukemia"
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      "source_id": "source-2026-07-26-008",
      "title": "Iowa State University via Newswise: Progranulin and white blood cell maturation",
      "publisher": "Iowa State University via Newswise",
      "url": "https://www.newswise.com/articles/finding-what-it-takes-to-make-a-white-blood-cell-could-lead-to-new-cancer-treatment",
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      "accessed_at": "2026-07-26T08:35:02.238-04:00",
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    "name": "The Machine Press",
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  "cite_this_report": {
    "title": "A Missing Protein Stops White Blood Cells From Growing Up",
    "publisher": "The Machine Press",
    "published_at": "2026-07-26T09:00:00.000-04:00",
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