{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:34:47Z","timestamp":1760402087971,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T00:00:00Z","timestamp":1617235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Ministry of Education, Culture, Sports, Science and Technology, Japan","award":["XXX"],"award-info":[{"award-number":["XXX"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Toll-like receptors (TLRs), evolutionarily conserved pattern recognition receptors, play an important role in innate immunity by recognizing microbial pathogen-associated molecular patterns. Koala retrovirus (KoRV), a major koala pathogen, exists in both endogenous (KoRV-A) and exogenous forms (KoRV-B to J). However, the expression profile of TLRs in koalas infected with KoRV-A and other subtypes is yet to characterize. Here, we investigated TLR expression profiles in koalas with a range of subtype infection profiles (KoRV-A only vs. KoRV-A with KoRV-B and\/or -C). To this end, we cloned partial sequences for TLRs (TLR2\u201310 and TLR13), developed real-time PCR assays, and determined TLRs mRNA expression patterns in koala PBMCs and\/or tissues. All the reported TLRs for koala were expressed in PBMCs, and variations in TLR expression were observed in koalas infected with exogenous subtypes (KoRV-B and KoRV-C) compared to the endogenous subtype (KoRV-A) only, which indicates the implications of TLRs in KoRV infection. TLRs were also found to be differentially expressed in koala tissues. This is the first report of TLR expression profiles in koala, which provides insights into koala\u2019s immune response to KoRV infection that could be utilized for the future exploitation of TLR modulators in the maintenance of koala health.<\/jats:p>","DOI":"10.3390\/ani11040983","type":"journal-article","created":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T07:23:17Z","timestamp":1617261797000},"page":"983","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Toll-Like Receptor Expression Profiles in Koala (Phascolarctos cinereus) Peripheral Blood Mononuclear Cells Infected with Multiple KoRV Subtypes"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4806-9843","authenticated-orcid":false,"given":"Mohammad Enamul Hoque","family":"Kayesh","sequence":"first","affiliation":[{"name":"Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Department of Microbiology and Public Health, Faculty of Animal Science and Veterinary Medicine, Patuakhali Science and Technology University, Barishal 8210, Bangladesh"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6224-2986","authenticated-orcid":false,"given":"Md Abul","family":"Hashem","sequence":"additional","affiliation":[{"name":"Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Department of Health, Chattogram City Corporation, Chattogram 4000, Bangladesh"},{"name":"Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4403-2018","authenticated-orcid":false,"given":"Kyoko","family":"Tsukiyama-Kohara","sequence":"additional","affiliation":[{"name":"Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,1]]},"reference":[{"key":"ref_1","unstructured":"Woinarski, J., and Burbidge, A.A. 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