{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T14:33:20Z","timestamp":1781620400596,"version":"3.54.5"},"reference-count":48,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T00:00:00Z","timestamp":1697068800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"LEUCINEBASS project"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The newly discovered IgT+ B cell is thought to play a dominant role in mucosal immunity, but limited studies have examined its distribution in fish species, hindering our understanding of its function. This study investigated IgT and poly Ig receptor (pIgR) mRNA+ cell distribution in Atlantic salmon (Salmo salar) gut using RNAscope in situ hybridization (ISH) and assessed the effects of vaccination. The pyloric caeca, mid-intestine (first and second parts), and posterior segment in two weight stages (Group 1: avg. 153 g, Group 2: avg. 1717 g) were examined in both vaccinated and unvaccinated fish. ISH revealed more IgT mRNA+ cells in the second part of the midgut compared to other intestinal segments, as well as a higher number of positive cells in Group 2 (older fish). In line with previous findings, intraperitoneal vaccination had no significant impact on the number of IgT+ transcripts. IgT mRNA+ cells were found mostly in the lamina propria and near capillaries, while pIgR was registered in both the lamina propria and mucosa. Interestingly, vaccinated fish presented adhesions and granulomatous tissue in the peritoneum, with both IgT and pIgR mRNA+ cells. Taken together, these results suggest that the distribution of IgT mRNA+ cells in the intestine of Atlantic salmon is region-specific and is not affected by intraperitoneal vaccination but varies with fish age.<\/jats:p>","DOI":"10.3390\/ani13203191","type":"journal-article","created":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T12:46:13Z","timestamp":1697114773000},"page":"3191","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["The Distribution of IgT mRNA+ Cells in the Gut of the Atlantic Salmon (Salmo salar L.)"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0395-899X","authenticated-orcid":false,"given":"Pedro Luis","family":"Castro","sequence":"first","affiliation":[{"name":"GIA-ECOAQUA, Universidad de Las Palmas de Gran Canaria, 35001 Telde, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-5124-2785","authenticated-orcid":false,"given":"Fran","family":"Barac","sequence":"additional","affiliation":[{"name":"Unit of Anatomy, Veterinary Faculty, Norwegian University of Life Sciences, 1433 \u00c5s, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tom Johnny","family":"Hansen","sequence":"additional","affiliation":[{"name":"Matre Research Station, Institute of Marine Research, 5984 Matredal, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Per Gunnar","family":"Fjelldal","sequence":"additional","affiliation":[{"name":"Matre Research Station, Institute of Marine Research, 5984 Matredal, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivar","family":"Hordvik","sequence":"additional","affiliation":[{"name":"Institute of Biology, University of Bergen, 5007 Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4683-0088","authenticated-orcid":false,"given":"H\u00e5vard","family":"Bj\u00f8rgen","sequence":"additional","affiliation":[{"name":"Unit of Anatomy, Veterinary Faculty, Norwegian University of Life Sciences, 1433 \u00c5s, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erling Olaf","family":"Koppang","sequence":"additional","affiliation":[{"name":"Unit of Anatomy, Veterinary Faculty, Norwegian University of Life Sciences, 1433 \u00c5s, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1007\/s00251-020-01195-1","article-title":"Immunoglobulins in teleosts","volume":"73","author":"Bilal","year":"2021","journal-title":"Immunogenetics"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1038\/ni.1913","article-title":"IgT, a primitive immu-noglobulin class specialized in mucosal immunity","volume":"11","author":"Zhang","year":"2010","journal-title":"Nat. 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