{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T03:46:06Z","timestamp":1767843966378,"version":"3.49.0"},"reference-count":53,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,12]],"date-time":"2025-08-12T00:00:00Z","timestamp":1754956800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of Allergy and Infectious Diseases","award":["AI106153"],"award-info":[{"award-number":["AI106153"]}]},{"name":"National Institute of Allergy and Infectious Diseases","award":["AI142939"],"award-info":[{"award-number":["AI142939"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Anthrax remains a formidable bioterrorism threat for which new, optimized and thermostable vaccines are needed. We previously demonstrated that five immunizations of rabbits with a multiple-antigenic-peptide (MAP) vaccine in either Freund\u2019s adjuvant or human-use adjuvants can elicit antibody (Ab) against the loop-neutralizing determinant (LND), a cryptic neutralizing epitope in the 2\u03b22-2\u03b23 loop of protective antigen from Bacillus anthracis (B. anthracis), which mediates complete protection of rabbits from inhalation spore challenge with the B. anthracis Ames strain. To develop a more immunogenic vaccine, we molecularly constructed a virus-like particle (VLP) vaccine, comprising the Woodchuck hepatitis core antigen capsid (WHcAg) displaying 240 copies of the LND epitope on each nanoparticle. Initial studies showed that the LND-VLP was immunogenic in rabbits following two immunizations, and passive transfer of the rabbit sera into A\/J mice conferred complete protection from aerosol challenge with B. anthracis. Further optimization of the vaccine revealed that the lyophilized LND-VLP vaccine was capable of eliciting highly protective levels of neutralizing antibody with two immunizations, and in some rabbits, a single immunization, using human-use adjuvants. A lyophilized LND-VLP nanoparticle vaccine may be an effective stand-alone vaccine or may complement PA-based vaccines as a future pre- or post-exposure vaccine for anthrax.<\/jats:p>","DOI":"10.3390\/microorganisms13081878","type":"journal-article","created":{"date-parts":[[2025,8,12]],"date-time":"2025-08-12T15:51:02Z","timestamp":1755013862000},"page":"1878","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Lyophilizable Nanoparticle Anthrax Vaccine Targeting the Loop-Neutralizing Determinant in Protective Antigen from Bacillus anthracis"],"prefix":"10.3390","volume":"13","author":[{"given":"Jon","family":"Oscherwitz","sequence":"first","affiliation":[{"name":"Division of Hematology-Oncology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA"},{"name":"Veterans Administration Ann Arbor Healthcare System, 2215 Fuller Road, Ann Arbor, MI 48105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kemp","family":"Cease","sequence":"additional","affiliation":[{"name":"Division of Hematology-Oncology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA"},{"name":"Veterans Administration Ann Arbor Healthcare System, 2215 Fuller Road, Ann Arbor, MI 48105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Milich","sequence":"additional","affiliation":[{"name":"VLP Biotech, Inc., 3030 Bunker Hill St., Ste 117D, San Diego, CA 92109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tod","family":"Merkel","sequence":"additional","affiliation":[{"name":"Division of Bacterial, Parasitic, and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, Food and Drug Agency, Silver Spring, MD 20993, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7113-6998","authenticated-orcid":false,"given":"Thomas","family":"Braun","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, University of Michigan, Ann Arbor, MI 48105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fen","family":"Yu","sequence":"additional","affiliation":[{"name":"Division of Hematology-Oncology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3803-9157","authenticated-orcid":false,"given":"David C.","family":"Whitacre","sequence":"additional","affiliation":[{"name":"VLP Biotech, Inc., 3030 Bunker Hill St., Ste 117D, San Diego, CA 92109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"621","DOI":"10.1186\/s12879-016-1951-y","article-title":"Alternative pre-approved and novel therapies for the treatment of anthrax","volume":"16","author":"Head","year":"2016","journal-title":"BMC Infect. 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