{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T18:31:05Z","timestamp":1776277865598,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T00:00:00Z","timestamp":1753228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012014","name":"Kieikai Research Foundation","doi-asserted-by":"publisher","award":["2024C006"],"award-info":[{"award-number":["2024C006"]}],"id":[{"id":"10.13039\/501100012014","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Bovine endometritis is a common postpartum disease that significantly impairs reproductive performance and reduces economic sustainability in dairy and beef cattle. It is primarily caused by gram-negative and -positive bacteria, triggering strong inflammatory responses in the endometrium. Serum amyloid A (SAA) is an acute-phase protein and precursor of amyloid A (AA) in AA amyloidosis. In cattle, multiple SAA isoforms have been identified; however, the biological functions of SAA3 remain unclear. Hence, this study investigated the role of SAA3 in bovine endometrial epithelial cells (BEnEpCs) following stimulation with gram-negative or -positive bacterial antigens. BEnEpCs were treated with lipopolysaccharide (LPS) and lipoteichoic acid (LTA) and, subsequently, the expression levels of SAA3 and SAA1 mRNA were compared by real-time PCR. To further investigate protein-level changes, immunocytochemistry (ICC) was performed to assess the expressions of SAA3 and SAA1. These analyses revealed that SAA3 mRNA expression was significantly enhanced by LPS and LTA, whereas SAA1 mRNA remained undetectable or showed only minimal responsiveness. Notably, only SAA3 protein expression increased in response to stimulation. These results indicate that SAA3 plays a crucial role in the innate immune response of BEnEpCs against gram-negative bacteria. Our in vitro findings may facilitate understanding of the innate immune activity in bovine uterus.<\/jats:p>","DOI":"10.3390\/pathogens14080729","type":"journal-article","created":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T16:04:51Z","timestamp":1753286691000},"page":"729","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Serum Amyloid A3 Expression Is Enhanced by Gram-Negative Bacterial Stimuli in Bovine Endometrial Epithelial Cells"],"prefix":"10.3390","volume":"14","author":[{"given":"Kazuha","family":"Aoyagi","sequence":"first","affiliation":[{"name":"Laboratory of Food and Environmental Hygiene, Joint Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keishi","family":"Owaki","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Pathology, Joint Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Joint Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hiroki","family":"Sakai","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Pathology, Joint Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Joint Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Education and Research Center for Food Animal Health, Gifu University (GeFAH), 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Center for One Medicine Innovative Translational Research (COMIT), Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7290-2482","authenticated-orcid":false,"given":"Ayaka","family":"Okada","sequence":"additional","affiliation":[{"name":"Laboratory of Food and Environmental Hygiene, Joint Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Joint Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Education and Research Center for Food Animal Health, Gifu University (GeFAH), 1-1 Yanagido, Gifu 501-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1189-8392","authenticated-orcid":false,"given":"Yasuo","family":"Inoshima","sequence":"additional","affiliation":[{"name":"Laboratory of Food and Environmental Hygiene, Joint Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Joint Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan"},{"name":"Education and Research Center for Food Animal Health, Gifu University (GeFAH), 1-1 Yanagido, Gifu 501-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1516","DOI":"10.1016\/j.theriogenology.2005.08.021","article-title":"Defining postpartum uterine disease in cattle","volume":"65","author":"Sheldon","year":"2006","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.tvjl.2007.12.019","article-title":"Postpartum uterine disease and dairy herd reproductive performance: A review","volume":"176","author":"LeBlanc","year":"2008","journal-title":"Vet. 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