{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T08:51:34Z","timestamp":1785833494187,"version":"3.56.0"},"reference-count":33,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T00:00:00Z","timestamp":1633910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Opening Fund of Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River","award":["(No. NJTCCJSYSYS09)"],"award-info":[{"award-number":["(No. NJTCCJSYSYS09)"]}]},{"name":"The program for Changjiang Scholars and Innovative Research Teams in the University","award":["(No. IRT0848)"],"award-info":[{"award-number":["(No. IRT0848)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The spleen is a separate organ of the teleost, playing an essential role in immune reactions. The morphology of the spleen is different from the fish species. Little knowledge about the spleen structure and the blood splenic barrier (BSB) in Nile tilapia has been reported. To address this issue, we studied the histology of the spleen and the BSB in healthy Nile tilapia. The morphology of the spleen was observed, then H&amp;E staining, modified Jame\u2019s staining, and ultrastructural techniques were performed to portion the spleen into three subregions and analyze the location of components and fibers. Thereafter, vital staining of Nile tilapia with Trypan blue was conducted to elucidate the composition and function of BSB. Histologically, the spleen could be divided into three subregions (inner, middle, and outer). The venules, clumps of lymphocytes, and vessels were separately characterized features of the outer, middle, and inner layers. Post injection, Trypan blue was intercepted in the endotheliocytes of ellipsoids in the middle layer (i.p.) or was deposited to the reticular fibers surrounding the ellipsoids (i.v.). Additionally, the amount of Trypan blue was shown to be positively correlated to that of the Acid phosphatase expressed. In conclusion, the spleen could be portioned into three subregions, and the BSB lay in the middle layer, composed of the cuboidal-shaped endotheliocytes and the surrounding reticular fibers of the ellipsoid capillaries. The present study enriched the research of immune tissues and system in tilapia and provided reference for the study of spleen in other fish species.<\/jats:p>","DOI":"10.3390\/ani11102934","type":"journal-article","created":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T09:16:42Z","timestamp":1633943802000},"page":"2934","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Morphology of the Spleen in Oreochromis niloticus: Splenic Subregions and the Blood-Spleen Barrier"],"prefix":"10.3390","volume":"11","author":[{"given":"Yang","family":"He","sequence":"first","affiliation":[{"name":"Key Laboratory of Animal Disease and Human Health of Sichuan Province, Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang 611130, China"},{"name":"Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River, Neijiang Normal University, Neijiang 641000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erlong","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Animal Science and Technology, Northwest A&F University, Xianyang 712100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaiyu","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Animal Disease and Human Health of Sichuan Province, Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River, Neijiang Normal University, Neijiang 641000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Fan","sequence":"additional","affiliation":[{"name":"Neijiang City Academy of Agricultural Sciences, Neijiang 641000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Defang","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Aquaculture, College of Animal Science & Technology, Sichuan Agricultural University, Wenjiang 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qian","family":"Yang","sequence":"additional","affiliation":[{"name":"Laboratory Animal Center, Southwest Medical University, Longmatan District Xianglin Road No.1, Luzhou 646000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"734398","DOI":"10.1016\/j.aquaculture.2019.734398","article-title":"Flow cytometry and automatic blood cell analysis in striped bass Morone saxatilis (Walbaum, 1792): A new hematological approach","volume":"513","author":"Fazio","year":"2019","journal-title":"Aquaculture"},{"key":"ref_2","unstructured":"He, Y., Ding, Z., Marana, M.H., Dalsgaard, I., Rzgar, J., Heidi, M., Asma, K.M., Per, K.W., and Kurt, B. (2021). Immersion vaccines against Yersinia ruckeri infection in rainbow trout: Comparative effects of strain differences. J. Fish Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/j.fsi.2021.03.019","article-title":"Oral vaccination of Nile tilapia (Oreochromis niloticus) against francisellosis elevates specific antibody titres in serum and mucus","volume":"113","author":"Hoare","year":"2021","journal-title":"Fish Shellfish. Immunol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1111\/cen.13997","article-title":"A multicentre validation study for the EU-TIRADS using histological diagnosis as a gold standard","volume":"91","author":"Trimboli","year":"2019","journal-title":"Clin. Endocrinol."},{"key":"ref_5","unstructured":"Ferguson, H. (2006). A text and atlas of normal tissues in teleosts and their responses in disease. Syst. Pathol. Fish, 10\u201323."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1002\/aja.1001760303","article-title":"Mechanisms of splenic control of murine malaria: Reticular cell activation and the development of a blood-spleen barrier","volume":"176","author":"Weiss","year":"1986","journal-title":"Am. J. Anat."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3823","DOI":"10.1016\/j.psj.2020.05.012","article-title":"Morphological characterization of postembryonic development of blood\u2013spleen barrier in duck","volume":"99","author":"Xu","year":"2020","journal-title":"Poult. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1111\/j.1462-5822.2011.01741.x","article-title":"The role of the spleen in malaria","volume":"14","author":"Ferrer","year":"2012","journal-title":"Cell. Microbiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.tvjl.2015.01.013","article-title":"Identification and structural composition of the blood\u2013spleen barrier in chickens","volume":"204","author":"Zhang","year":"2015","journal-title":"Vet. J."},{"key":"ref_10","first-page":"33","article-title":"The novel histological evidence of the blood-spleen barrier in duck (Anas platyrhynchos)","volume":"34","author":"Sun","year":"2018","journal-title":"Histol. Histopathol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1002\/ar.20917","article-title":"Architecture of the blood-spleen barrier in the soft-shelled turtle, Pelodiseus sinensis","volume":"292","author":"Bao","year":"2009","journal-title":"Anat. Rec."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"4183","DOI":"10.1111\/are.14760","article-title":"Streptococcosis, Lactococcosis and Enterococcosis are potential threats facing cultured Nile tilapia (Oreochomis niloticus) production","volume":"51","author":"Younis","year":"2020","journal-title":"Aquacult. Res."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Aich, N., Paul, A., Choudhury, T.G., and Saha, H. (2021). Tilapia Lake Virus (TiLV) disease: Current status of understanding. Aquac. Fish.","DOI":"10.1016\/j.aaf.2021.04.007"},{"key":"ref_14","first-page":"495","article-title":"Multiplex PCR for simultaneous detection of Streptococcus agalactiae, Streptococcus iniae and Lactococcus garvieae: A case of S. agalactiae infection in cultured Nile tilapia (Oreochromis niloticus) and red tilapia (Oreochromis niloticus x Oreochromis mossambicus)","volume":"34","author":"Itsaro","year":"2012","journal-title":"Songklanakarin J. Sci. Technol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"430","DOI":"10.1016\/j.aquaculture.2017.03.014","article-title":"Identification of Tilapia Lake Virus in Egypt in Nile tilapia affected by \u2018summer mortality\u2019syndrome","volume":"473","author":"Fathi","year":"2017","journal-title":"Aquaculture"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.fsi.2021.02.017","article-title":"Modulation of the mucosal immune response of red tilapia (Oreochromis sp.) against columnaris disease using a biomimetic-mucoadhesive nanovaccine","volume":"112","author":"Kitiyodom","year":"2021","journal-title":"Fish Shellfish Immunol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"7025","DOI":"10.1016\/j.vaccine.2014.08.017","article-title":"A recombinant truncated surface immunogenic protein (tSip) plus adjuvant FIA confers active protection against Group B streptococcus infection in tilapia","volume":"32","author":"He","year":"2014","journal-title":"Vaccine"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1016\/j.fsi.2020.10.019","article-title":"Pathogenesis and immune response of Nile tilapia (Oreochromis niloticus) exposed to Tilapia lake virus by intragastric route","volume":"107","author":"Pierezan","year":"2020","journal-title":"Fish Shellfish Immunol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1111\/jfd.12347","article-title":"Experimental early pathogenesis of Streptococcus agalactiae infection in red tilapia Oreochromis spp.","volume":"39","author":"Iregui","year":"2016","journal-title":"J. Fish Dis."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1038\/nrmicro2745","article-title":"Modulating immunity as a therapy for bacterial infections","volume":"10","author":"Hancock","year":"2012","journal-title":"Nat. Rev. Microbiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1080\/24750263.2018.1460694","article-title":"Comparative study of haematology of two teleost fish (Mugil cephalus and Carassius auratus) from different environments and feeding habits","volume":"85","author":"Parrino","year":"2018","journal-title":"Eur. Zool. J."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Acar, \u00dc., Kesbi\u00e7, O.S., Y\u0131lmaz, S., \u0130nanan, B.E., Zemheri-Navruz, F., Terzi, F., Fazio, F., and Parrino, V. (2021). Effects of Essential Oil Derived from the Bitter Orange (Citrus aurantium) on Growth Performance, Histology and Gene Expression Levels in Common Carp Juveniles (Cyprinus carpio). Animals, 11.","DOI":"10.3390\/ani11051431"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Michalczyk-Wetula, D., Salwi\u0144ski, A., Popik, M., Jakubowska, M., and P\u0142onka, P.M. (2013). Splenic melanosis during normal murine C57BL\/6 hair cycle and after chemotherapy. Acta Biochim. Pol., 60.","DOI":"10.18388\/abp.2013_1987"},{"key":"ref_24","first-page":"359","article-title":"Application and effect of modified James staining","volume":"29","author":"Lin","year":"2009","journal-title":"J. Shanghai Jiaotong Univ. Med Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1084\/jem.138.3.607","article-title":"Identification of human B and T lymphocytes by scanning electron microscopy","volume":"138","author":"Polliack","year":"1973","journal-title":"J. Exp. Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"486","DOI":"10.17221\/3294-VETMED","article-title":"Innate and adaptive immunity in teleost fish: A review","volume":"56","author":"Uribe","year":"2011","journal-title":"Vet. Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.dci.2014.11.003","article-title":"Reduction of rainbow trout spleen size by splenectomy does not alter resistance against bacterial cold water disease","volume":"49","author":"Wiens","year":"2015","journal-title":"Dev. Comp. Immunol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1080\/01926230600867743","article-title":"Normal structure, function, and histology of the spleen","volume":"34","author":"Cesta","year":"2006","journal-title":"Toxicol. Pathol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1046\/j.1444-2906.2002.00558.x","article-title":"Entrapment and transport of foreign material in the spleen and kidney of Japanese conger Conger myriaster","volume":"68","author":"Furukawa","year":"2002","journal-title":"Fish. Sci."},{"key":"ref_30","first-page":"44","article-title":"Location of blood-spleen barrier of Pelteobagrus vachelli by Trypan blue staining","volume":"17","author":"He","year":"2021","journal-title":"S. China Fish. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1459","DOI":"10.1139\/f75-169","article-title":"Hepatic morphology and acid phosphatase localization in the channel catfish (Ictalurus punctatus)","volume":"32","author":"Kendall","year":"1975","journal-title":"J. Fish. Board Can."},{"key":"ref_32","first-page":"1749","article-title":"Pyrethroid insecticide, Lambda-Cyhalothrin impact on tissue acid phosphatase (ACP) activity of the fish, Etroplus Suratensis","volume":"9","author":"Vidhya","year":"2019","journal-title":"Pramana Res. J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/0167-5699(91)90108-6","article-title":"Barrier cells in the spleen","volume":"12","author":"Weiss","year":"1991","journal-title":"Immunol. Today"}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/11\/10\/2934\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:11:32Z","timestamp":1760166692000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/11\/10\/2934"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10,11]]},"references-count":33,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2021,10]]}},"alternative-id":["ani11102934"],"URL":"https:\/\/doi.org\/10.3390\/ani11102934","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10,11]]}}}