{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T04:05:15Z","timestamp":1775707515807,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,19]],"date-time":"2025-06-19T00:00:00Z","timestamp":1750291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["21K09450"],"award-info":[{"award-number":["21K09450"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>To clarify the physiological importance of the tryptophan catabolizing enzyme, indoleamine 2,3-dioxygenase, in human pregnancy, we have studied how the expression of this enzyme controls extravillous cytotrophoblast invasion into the decidua. We have generated an Ishikawa cell line stably transfected with a plasmid encoding indoleamine 2,3-dioxygenase under the control of a tetracycline inducible promoter. Using this Ishikawa cell line and extravillous cytotrophoblast cell line, HTR-8\/SVneo, we developed a quantitative in vitro trophoblast invasion assay. When trophoblast cells were cultured on a layer of Ishikawa cells expressing indoleamine 2,3-dioxygenase, tryptophan degradation was enhanced and trophoblast cell invasion was suppressed. These findings suggest that indoleamine 2,3-dioxygenase expressed in the decidua may play a role in regulating trophoblast invasion.<\/jats:p>","DOI":"10.3390\/ijms26125889","type":"journal-article","created":{"date-parts":[[2025,6,19]],"date-time":"2025-06-19T08:43:58Z","timestamp":1750322638000},"page":"5889","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Indoleamine 2,3-Dioxygenase Regulates Placental Trophoblast Cell Invasion"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6542-3408","authenticated-orcid":false,"given":"Yoshiki","family":"Kudo","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Sugimoto","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/j.ajog.2017.05.067","article-title":"Placenta accreta spectrum: Pathophysiology and evidence-based anatomy for prenatal ultrasound imaging","volume":"218","author":"Jauniaux","year":"2018","journal-title":"Am. 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