{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T23:04:04Z","timestamp":1788822244704,"version":"build-2803163510"},"reference-count":49,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T00:00:00Z","timestamp":1768348800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JST","award":["JPMJSP2136"],"award-info":[{"award-number":["JPMJSP2136"]}]},{"name":"Joint Usage\/Research Center for Developmental Medicine, IMEG, Kumamoto University"},{"name":"Sasakawa Scientific Research Grant from the Japan Science Society, 3MT award from Kyushu University"},{"name":"collaborative research fund from the Kumamoto University Institute of Developmental Medicine"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Neurogenesis is tightly regulated by complex interactions among neural stem and progenitor cells (NSCs\/NPCs), blood vessels, microglia, and extracellular matrix components within the neurogenic niche. In the embryonic brain, NSCs reside along the ventricular surface, where cerebrospinal fluid (CSF) directly regulates their proliferation. Here, we identify Akhirin (AKH) as a critical regulator that preserves the integrity of the NSC niche during mouse brain development. At embryonic day 14.5, AKH is secreted and enriched at the apical surface of choroid plexus epithelial cells and the ventricular lining. Loss of AKH leads to increases the inflammatory cytokine expression in the CSF and disrupts NSC niche homeostasis. Furthermore, AKH is cleaved upon inflammatory stimulation, and its LCCL domain directly binds bacteria, thereby preventing their spread. These findings reveal that AKH functions as a protective barrier molecule within the developing neurogenic niche, providing immune protection and preserving NSC niche homeostasis during periods when the innate immune defenses are still immature.<\/jats:p>","DOI":"10.3390\/cells15020151","type":"journal-article","created":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T15:47:37Z","timestamp":1768405657000},"page":"151","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Akhirin Functions as an Innate Immune Barrier to Preserve Neurogenic Niche Homeostasis During Mouse Brain Development"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9363-7793","authenticated-orcid":false,"given":"Mikiko","family":"Kudo","sequence":"first","affiliation":[{"name":"Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan"},{"name":"Department of Stem Cell Biology, Graduate School of System Life Sciences, Kyushu University, Fukuoka 819-0395, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tenta","family":"Ohkubo","sequence":"additional","affiliation":[{"name":"Department of Stem Cell Biology, Graduate School of System Life Sciences, Kyushu University, Fukuoka 819-0395, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taichi","family":"Sugawara","sequence":"additional","affiliation":[{"name":"Department of Histology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takashi","family":"Irie","sequence":"additional","affiliation":[{"name":"Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan"},{"name":"Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Hatakeyama","sequence":"additional","affiliation":[{"name":"Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-8556, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1334-6869","authenticated-orcid":false,"given":"Shigehiko","family":"Tamura","sequence":"additional","affiliation":[{"name":"Department of Molecular Cell Biology, Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7102-6513","authenticated-orcid":false,"given":"Kenji","family":"Shimamura","sequence":"additional","affiliation":[{"name":"Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-8556, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomohiko","family":"Wakayama","sequence":"additional","affiliation":[{"name":"Department of Histology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0988-4706","authenticated-orcid":false,"given":"Naoki","family":"Matsuo","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 819-0395, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5901-9628","authenticated-orcid":false,"given":"Kinichi","family":"Nakashima","sequence":"additional","affiliation":[{"name":"Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3687-452X","authenticated-orcid":false,"given":"Takahiro","family":"Masuda","sequence":"additional","affiliation":[{"name":"Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4564-9757","authenticated-orcid":false,"given":"Kunimasa","family":"Ohta","sequence":"additional","affiliation":[{"name":"Department of Stem Cell Biology, Graduate School of System Life Sciences, Kyushu University, Fukuoka 819-0395, Japan"},{"name":"Department of Stem Cell Biology, Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, 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