{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:31:39Z","timestamp":1760146299596,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,10,25]],"date-time":"2024-10-25T00:00:00Z","timestamp":1729814400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"USDA National Institute of Food and Agriculture (NIFA)","award":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"],"award-info":[{"award-number":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"]}]},{"name":"Canadian Government and the Bill and Melinda Gates Foundation","award":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"],"award-info":[{"award-number":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"]}]},{"DOI":"10.13039\/100000199","name":"United States Department of Agriculture","doi-asserted-by":"publisher","award":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"],"award-info":[{"award-number":["2020-67015-31809","108525","ARS-USDA CRIS 2090-32000-040-00-D"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Bovine babesiosis caused by the tick-borne apicomplexan parasite Babesia bovis remains a threat for cattle worldwide, and new vaccines are needed. We propose using immune-subdominant (ISD) antigens as alternative vaccine candidates. We first determined that RAP-1 NT and RRA are subdominant antigens using recombinant antigens in ELISAs against sera from B. bovis-protected cattle. Protected animals demonstrated high antibody responses against the known immunodominant rRAP-1 CT antigen, but significantly lower levels against the rRAP-1 NT and rRRA antigens. Next, a group of cattle (n = 6) was vaccinated with rRRA and rRAP-1 NT using a FliC\u2013Emulsigen mix as the adjuvant, and there was a control group (n = 6) with the adjuvant mix alone. All but one immunized animal demonstrated elicitation of strong humoral immune responses against the two ISD antigens. Acute babesiosis occurred in both groups of cattle upon a challenge with the virulent B. bovis, but a significant delay in the average rate of decrease in hematocrit in the vaccinated group, and an early monocyte response, was found in half of the vaccinated animals. In conclusion, we confirmed the immune subdominance of rRRA and rRAP-1 NT and the ability of FliC to increase immunogenicity of ISD antigens and generate useful information toward developing future subunit vaccines against B. bovis.<\/jats:p>","DOI":"10.3390\/vaccines12111215","type":"journal-article","created":{"date-parts":[[2024,10,25]],"date-time":"2024-10-25T10:50:08Z","timestamp":1729853408000},"page":"1215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Evaluation of the Use of Sub-Immunodominant Antigens of Babesia bovis with Flagellin C Adjuvant in Subunit Vaccine Development"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6845-3204","authenticated-orcid":false,"given":"Manuel J.","family":"Rojas","sequence":"first","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"},{"name":"Animal Health Department, Universidad Nacional de Colombia, Bogota 111321, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Reginaldo G.","family":"Bastos","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"},{"name":"Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinna A.","family":"Navas","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0260-7813","authenticated-orcid":false,"given":"Heba F.","family":"Alzan","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"},{"name":"Parasitology and Animal Diseases Department, National Research Center, Giza 12622, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacob M.","family":"Laughery","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul A.","family":"Lacy","sequence":"additional","affiliation":[{"name":"Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2680-6091","authenticated-orcid":false,"given":"Massaro W.","family":"Ueti","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"},{"name":"Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6112-2931","authenticated-orcid":false,"given":"Carlos E.","family":"Suarez","sequence":"additional","affiliation":[{"name":"Department of Veterinary Microbiology & Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA"},{"name":"Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1186\/s13071-023-05885-z","article-title":"Exploring the landscape of Babesia bovis vaccines: Progress, challenges, and opportunities","volume":"16","author":"Santos","year":"2023","journal-title":"Parasites Vectors"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Almaz\u00e1n, C., Scimeca, R.C., Reichard, M.V., and Mosqueda, J. 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