{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T17:54:52Z","timestamp":1790013292682,"version":"4.0.1"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,18]],"date-time":"2021-11-18T00:00:00Z","timestamp":1637193600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008982","name":"National Science Foundation","doi-asserted-by":"publisher","award":["IOS: 1749427"],"award-info":[{"award-number":["IOS: 1749427"]}],"id":[{"id":"10.13039\/501100008982","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Infections by Frog Virus 3 (FV3) and other ranavirus genus members are significantly contributing to global amphibian decline. The Xenopus laevis frog is an ideal research platform upon which to study the roles of distinct frog leukocyte populations during FV3 infections. Frog macrophages (M\u03a6s) are integrally involved during FV3 infection, as they facilitate viral dissemination and persistence but also participate in immune defense against this pathogen. In turn, M\u03a6 differentiation and functionality depend on the colony-stimulating factor-1 receptor (CSF-1R), which is ligated by CSF-1 and iterleukin-34 (IL-34) cytokines. Our past work indicated that X. laevis CSF-1 and IL-34 give rise to morphologically and functionally distinct frog M\u03a6 subsets, and that these CSF-1- and IL-34-M\u03a6s respectively confer susceptibility and antiviral resistance to FV3. Because FV3 targets the frog kidneys and establishes chronic infections therein, presently we examined the roles of the frog CSF-1- and IL-34-M\u03a6s in seeding and maintaining these chronic kidney infections. Our findings indicate that the frog CSF-1-M\u03a6s result in more prominent kidney FV3 infections, which develop into greater reservoirs of lingering FV3 marked by infiltrating leukocytes, fibrosis, and overall immunosuppressive states. Moreover, the antiviral effects of IL-34-M\u03a6s are short-lived and are lost as FV3 infections progress.<\/jats:p>","DOI":"10.3390\/v13112299","type":"journal-article","created":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T02:43:31Z","timestamp":1637289811000},"page":"2299","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["The Roles of Amphibian (Xenopus laevis) Macrophages during Chronic Frog Virus 3 Infections"],"prefix":"10.3390","volume":"13","author":[{"given":"Muhammad Riadul Haque","family":"Hossainey","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, George Washington University, Washington, DC 20052, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amulya","family":"Yaparla","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, George Washington University, Washington, DC 20052, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kelsey A.","family":"Hauser","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, George Washington University, Washington, DC 20052, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tyler E.","family":"Moore","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, George Washington University, Washington, DC 20052, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leon","family":"Grayfer","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, George Washington University, Washington, DC 20052, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1200","DOI":"10.1017\/S0950268806007679","article-title":"Emerging epidemic diseases of frogs in Britain are dependent on the source of ranavirus agent and the route of exposure","volume":"135","author":"Cunningham","year":"2007","journal-title":"Epidemiol. 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