{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T10:05:48Z","timestamp":1789553148444,"version":"build-2803163510"},"reference-count":54,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:00:00Z","timestamp":1789516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["7R01AI176537-03"],"award-info":[{"award-number":["7R01AI176537-03"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["1R01HL180677-01A1"],"award-info":[{"award-number":["1R01HL180677-01A1"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["5R21AI191628-02"],"award-info":[{"award-number":["5R21AI191628-02"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"award":["7R01AI176537-03"],"award-info":[{"award-number":["7R01AI176537-03"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]},{"award":["1R01HL180677-01A1"],"award-info":[{"award-number":["1R01HL180677-01A1"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]},{"award":["5R21AI191628-02"],"award-info":[{"award-number":["5R21AI191628-02"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Acute lung injury (ALI) is characterized by alveolar-capillary barrier disruption, increased pulmonary permeability, impaired gas exchange, and inflammation. Lipopolysaccharide (LPS), a potent microbial trigger of inflammation, is widely used to model ALI. Short palate, lung, and nasal epithelial clone 1 (SPLUNC1), also known as BPIFA1, is an abundant surfactant-like protein secreted by the airway epithelium with antimicrobial and immunomodulatory functions. However, its role in endotoxin-induced lung injury remains incompletely understood. We compared pulmonary responses to LPS in wild-type and SPLUNC1\/BPIFA1-knockout mice. Mice received intranasal PBS or 5 \u03bcg LPS were evaluated 24 h later by bronchoalveolar lavage, histology, cytospin, flow cytometry, qPCR, ELISA, and whole-lung RNA sequencing. Compared with WT mice, LPS-challenged KO mice exhibited greater inflammatory-cell accumulation, enhanced neutrophil recruitment, increased cytokine and chemokine expression, and greater histologic lung injury. Transcriptomic analyses showed preferential activation of TNF\u03b1\/NF-\u03baB, IL-6-JAK-STAT3, complement, cytokine\/chemokine, myeloid\/neutrophil, and stress-response in KO lungs. These findings identify SPLUNC1\/BPIFA1 as an epithelial-derived regulator that restrains endotoxin-induced inflammatory signaling, neutrophil recruitment, and tissue injury. Collectively, these results support a protective role for SPLUNC1\/BPIFA1 in acute pulmonary inflammation and provide a rationale for investigating SPLUNC1\/BPIFA1 augmentation to mitigate ALI. Further studies evaluating SPLUNC1-based interventions in preclinical models are warranted.<\/jats:p>","DOI":"10.3390\/biom16091349","type":"journal-article","created":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T09:06:37Z","timestamp":1789549597000},"page":"1349","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["SPLUNC1\/BPIFA1 Restrains Neutrophil-Dominant Inflammation and Coordinated Inflammatory Gene Programs During LPS-Induced Lung Injury"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-8743-9406","authenticated-orcid":false,"given":"Hexin","family":"Lu","sequence":"first","affiliation":[{"name":"Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15260, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2028-2087","authenticated-orcid":false,"given":"Yuanpu Peter","family":"Di","sequence":"additional","affiliation":[{"name":"Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15260, USA"},{"name":"Department of Cellular & Molecular Medicine, Center for Translational Science, Herbert Wertheim College of Medicine, Florida International University, Port St. Lucie, FL 34987, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.pccm.2024.04.002","article-title":"Mechanisms of pulmonary endothelial barrier dysfunction in acute lung injury and acute respiratory distress syndrome","volume":"2","author":"Su","year":"2024","journal-title":"Chin. 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