{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T08:27:01Z","timestamp":1787128021504,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"publisher","award":["2025YFC3409700"],"award-info":[{"award-number":["2025YFC3409700"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Bacterial infection triggered excessive inflammatory responses, yet the mechanisms linking inflammatory activation to immunometabolic adaptation remained incompletely understood. The mitochondrial translocator protein (TSPO) has been implicated in inflammatory activation and cellular metabolism. This study aimed to investigate the role of TSPO in inflammation mediated by Toll-like receptor 4 (TLR4). Herein, we integrated transcriptomic data from the human peripheral blood dataset GSE72829, and single-cell transcriptomic profiles from the CELLxGENE platform with cellular mechanistic experiments in BV2 microglia and RAW264.7 macrophages. Transcriptomic analyses revealed that TSPO expression was markedly upregulated in patients with bacterial infection (n = 52) and exhibited diagnostic potential to distinguish bacterial infection from healthy controls (HCs, n = 16) and viral infection (n = 92). TSPO-correlated genes were enriched in Toll-like receptor (TLR) signaling, inflammatory response, and immunometabolic pathways. Mechanistically, TSPO interacted with TLR4 and selectively modulated TLR4-driven inflammatory activation. TSPO deficiency augmented lipopolysaccharide (LPS) induced tumor necrosis factor\u2011\u03b1 (TNF-\u03b1) and interleukin\u20116 (IL-6) secretion, accompanied by disrupted Ca2+ homeostasis, impaired cholesterol balance, and compensatory metabolic remodeling characterized by elevated L-lactate and sustained Adenosine triphosphate (ATP) levels. Collectively, these findings identified TSPO as an immunometabolic regulator bridging TLR4 signaling and metabolic adaptation during inflammatory activation. Besides, TSPO represented a promising biomarker and therapeutic target to limit exaggerated inflammatory responses.<\/jats:p>","DOI":"10.3390\/ijms27167336","type":"journal-article","created":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T12:01:26Z","timestamp":1786968086000},"page":"7336","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["TSPO\u00a0Regulates TLR4-Mediated Inflammation Through Calcium Homeostasis and Immunometabolic Adaptation"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8302-8222","authenticated-orcid":false,"given":"Xiaoqin","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Neurology, Huashan Hospital, Fudan University and Institute of Neurology, Fudan University, National Center for Neurological Disorders, Shanghai 200040, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yaru","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Immune Response and Immunotherapy, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101408, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5008-296X","authenticated-orcid":false,"given":"Bo","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Immune Response and Immunotherapy, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoni","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Neurology, Huashan Hospital, Fudan University and Institute of Neurology, Fudan University, National Center for Neurological Disorders, Shanghai 200040, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8108-9013","authenticated-orcid":false,"given":"Xiangjun","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Neurology, Huashan Hospital, Fudan University and Institute of Neurology, Fudan University, National Center for Neurological Disorders, Shanghai 200040, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,17]]},"reference":[{"key":"ref_1","unstructured":"Antimicrobial Resistance Collaborators (2022). 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