{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T18:30:29Z","timestamp":1790620229722,"version":"4.1.0"},"reference-count":39,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T00:00:00Z","timestamp":1673481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Society for the Promotion of Science (JSPS)"},{"name":"Program for the Promotion of Basic and Applied Research for Innovations in Bio-oriented Industry"},{"name":"Livestock Promotional Subsidy from the Japan Racing Association"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis. However, the propagation and distribution of BLV after primary infection still need to be fully elucidated. Here, we experimentally infected seven cattle with BLV and analyzed the BLV proviral load (PVL) in the blood and various organs. BLV was first detected in the blood of the cattle after one week, and the blood PVL increased for three weeks after infection. The PVL was maintained at a high level in five cattle, while it decreased to a low or medium level in two cattle. BLV was distributed in various organs, such as the heart, lung, liver, kidney, abomasum, and thymus, and, notably, in the spleen and lymph nodes. In cattle with a high blood PVL, BLV was detected in organs other than the spleen and lymph nodes, whereas in those with a low blood PVL, BLV was only detected in the spleen and lymph nodes. The amount of BLV in the organs was comparable to that in the blood. Our findings point to the possibility of estimating the distribution of BLV provirus in organs, lymph nodes, and body fluids by measuring the blood PVL, as it was positively correlated with the biodistribution of BLV provirus in the body of BLV infection during early stages.<\/jats:p>","DOI":"10.3390\/pathogens12010130","type":"journal-article","created":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T01:30:26Z","timestamp":1673573426000},"page":"130","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Correlation between the Biodistribution of Bovine Leukemia Virus in the Organs and the Proviral Load in the Peripheral Blood during Early Stages of Experimentally Infected Cattle"],"prefix":"10.3390","volume":"12","author":[{"given":"Junko","family":"Kohara","sequence":"first","affiliation":[{"name":"Animal Health Group, Animal Research Center, Hokkaido Research Organization, Shintoku 081-0038, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2414-3247","authenticated-orcid":false,"given":"Lanlan","family":"Bai","sequence":"additional","affiliation":[{"name":"Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan"},{"name":"Graduate School of Science and Engineering, Iwate University, Morioka 020-8551, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9648-0480","authenticated-orcid":false,"given":"Shin-nosuke","family":"Takeshima","sequence":"additional","affiliation":[{"name":"Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan"},{"name":"Department of Food and Nutrition, Jumonji University, 2-1-28 Sugasawa, Niiza 352-8510, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuki","family":"Matsumoto","sequence":"additional","affiliation":[{"name":"Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tsunao","family":"Hirai","sequence":"additional","affiliation":[{"name":"Animal Health Group, Animal Research Center, Hokkaido Research Organization, Shintoku 081-0038, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoko","family":"Aida","sequence":"additional","affiliation":[{"name":"Virus Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan"},{"name":"Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"328","DOI":"10.3389\/fmicb.2013.00328","article-title":"Mechanisms of pathogenesis induced by bovine leukemia virus as a model for human T-cell leukemia virus","volume":"4","author":"Aida","year":"2013","journal-title":"Front. 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